A portion of the disclosure of this patent document contains material which is subject to copyright protection. The copyright owner has no objection to the facsimile reproduction by anyone of the patent document or the patent disclosure, as it appears in the Patent and Trademark Office patent file or records, but otherwise reserves all copyright rights whatsoever.
FIELD OF INVENTION
The present invention relates to calibration of a handheld rangefinder to match the ballistics of a specific firing device, such as a bow using bow sight and a calibration sheet, or such as pistol or rifle, with specific projectiles, using a relative target and relative target icon. The present invention also relates to devices such as handheld rangefinders and methods for calibrating the rangefinder for an individual bow and arrow or rifle and cartridge.
PRIOR ART
Firing Device and Projectiles
Firing devices such as bows, crossbows, rifles, pistols, other guns, and artillery have been used for sport, hunting, law enforcement, and military. Each firing device is used to launch a projectile such as an arrow, dart, bullet, ball, or explosive shell along a projectile trajectory.
An arrow is typically shot using the arms to pull back the bow string, and to aim and sight by holding the bow and arrow next to the archer's eye. More recently bow sights have been added to all types of bows. Typically, a bow sight comprises a plurality of pins that may be adjusted by the archer for aiming at targets at different distances. Some bow sights have a single adjustable pin that is moved to the match the distance to the target.
FIG. 1A shows a user (in this case, an archer) 100 with a bow 102 with a bow sight 110 and an arrow 104. The bow sight 110 comprises pins adjusted e.g., for twenty yards, forty yards, and sixty yards, namely a twenty-yard pin, a forty-yard pin, and a sixty-yard pin, respectively.
FIG. 1B shows a rifle with a rifle scope 302. Rifle balls and/or bullets are typically shot from a gun using the arms to aim and sight by aligning the gun sights or gun scope reticle with the target.
5 shows an example of a bow sight 110 with pins adjusted for twenty yards, forty yards, and sixty yards, namely a twenty-yard pin 220, a forty-yard pin 240, and a sixty-yard pin 260, respectively.
Artillery balls and shells are typically shot by adjusting the aim mechanically.
Arrows, spears, balls, bullets, and shells when fired follow a ballistic trajectory. Such projectiles, which are not self-propelled, move through air according to a generally parabolic (ballistic) curve due primarily to the effects of gravity and air drag. The vertex form for a parabolic equation is y=a(x−h)2+k, where the vertex is the point (h, k) and a negative a (−a) is a maximum. The standard form of the parabolic equation is y=ax2+bx+c, where h=−b/(2a) and k=c−b2/(4a).
Rifle and bow scopes conventionally have been fitted with reticles of different forms. Some have horizontal and vertical cross hairs. Others reticles such as mil-dot add evenly spaced dots for elevation and windage along the cross hairs. U.S. Design Pat. D522,030, issued on May 30, 2006, shows a SR reticle and graticle design for a scope. Various reticles, such as Multi Aim Point (MAP) and Dot are provided, for example, by Hawke Optics (http://hawkeoptics.com). These reticles are fixed in that the display does not change based on range information. Also, these reticles indicate the approximate hold-over position in that they are positioned under the center of the scope, i.e. below where the cross hairs intersect. They are not necessarily precise, for example, for a specific bow and archer or for a specific rifle and ammunition but are approximation for the general case.
Hunters and other firearm and bow users commonly utilize handheld rangefinders (see device 10 in FIG. 3) to determine ranges to targets. Generally, handheld rangefinders utilize lasers to acquire ranges for display to a user. Utilizing the displayed ranges, the user makes sighting corrections to facilitate accurate shooting.
For example, U.S. Pat. No. 7,658,031, issued Feb. 9, 2010, discloses handheld rangefinder technology from Bushnell, Inc, and is hereby included by reference. As shown in FIG. 1, a handheld rangefinder device 10 generally includes a range sensor 12 operable to determine a first range to a target, a tilt sensor 14 operable to determine an angle to the target relative to the device 10, and a computing element 16, coupled with the range sensor 12 and the tilt sensor 14, operable to determine a hold over value based on the first range and the determined angle. The range information is displayed on a display 30. A housing 20 contains the elements of the device 10. Bushnell Angle Range Compensation (ARC) rangefinders show the first linear range to the target and also show an angle and a second range, which represents the horizontal distance to the target. Handheld rangefinders, telescope sights, and other optical devices typically comprise a laser range sensor and an inclinometer.
The range information is superimposed over the image that is seen through the optics. For example, U.S. Design Pat. D453,301, issued Feb. 5, 2002, shows an example of a design for a display for a Bushnell rangefinder, and is hereby included by reference. FIG. 4 shows an exemplary display 30 appearing in a handheld rangefinder device 10.
With convention rangefinder and a bow sight there is no correlation between the display of the rangefinder and the user's individual bow sight. To make an effective shot requires several steps. First the user operates the rangefinder to range the target. Second, the user raises the bow and uses the bow sight pins to visualize the shooting area. Third, the user lowers the bow and raises the rangefinder again to find the range to each object that may be a potential obstacle. Fourth, the user lowers the rangefinder and raises the bow to make the shot.
With convention rangefinder and a rifle there is no correlation between the display of the rangefinder and the user's individual rifle sight or scope. To make an effective shot requires several steps.
All of the movement and time taken during these steps will likely be noticed by the target and allow the target an opportunity to move resulting in having to repeat the process or miss the shot altogether.
Further in order to show an accurate aiming point a rangefinder needs to be calibrated to a specific bow and arrow, rifle and cartridge, or other firearm and its projectile.
What is needed is an improved rangefinder with a display that provides information regarding a projectile trajectory so that a user is informed whether or not there is a clear shot. Further, the improved rangefinder dynamically indicates positions along the trajectory based on ranges accurately determined by the rangefinder, such that the user is informed about the distance to specific obstacles and whether or not the obstacles would interfere with the trajectory of the projectile.
Further, for bow use, the indicators on the display need to correspond to the bow sight pins, and a calibration method to calibrate the rangefinder to the archer's specific bow and arrows.
Further, for higher speed firing devices, what is needed is an improved display that provides a relative aiming point relative to a reference with a predetermined size or height, so the user can visualize where to aim, and a calibration method to calibrate the rangefinder to a specific firing device (such as a pistol, rifle, gun, or crossbow) and its specific projectile.
BACKGROUND OF THE INVENTION
Our patented Flight Path® technology currently available in Leupold RX-FullDraw 5 and RX-1400i True Ballistic Range/Wind (TBR/W) Gen 2, does an excellent job of handling elevation by providing an aiming point corrected for shoot angle, distance, and ballistics.
For example, our U.S. Pat. No. 9,057,587, issued Jun. 16, 2015, discloses and claims a smart rangefinder which: a) provides an aiming point; b) provides a digital rangefinder having a video camera and high-resolution digital display; and c) displays an aiming point, corrected for range and wind effect anywhere on the high-resolution display.
U.S. Pat. No. 9,057,587 also discloses the use of a smart phone, such as an iPhone, as a display for a digital rangefinder.
SUMMARY OF THE INVENTION
The present invention solves the above-described problems and provides a distinct advance in the art of rangefinder display and rangefinder ballistic curve calibration. More particularly, the invention provides a display that provides a relative aiming point relative to a reference with a predetermined size or height, so the user can visualize where to aim. Such information facilitates accurate, effective, and safe firearm use.
In one embodiment, the present invention provides a rangefinder device for determining projectile trajectory information. The device generally includes a range sensor operable to determine a first range to a target, a tilt sensor operable to determine an angle to the target relative to the device, and a computing element, coupled with the range sensor and the tilt sensor, operable to determine a projectile trajectory and to provide indicators which inform the user whether or not there is a clear shot.
In other embodiments, a display is provided having a distance indicator and one or more path indicators, such as a twenty-yard indicator.
In other embodiments, a display dynamically illuminates one or more of a plurality of selectable path indicators to provide information regarding the projectile trajectory. One of the plurality of selectable path indicators is an aiming point, such as a twenty yard aiming point
Various embodiments are calibrated using a field target, a calibration sheet, or a relative target to calibrate the rangefinder device to an individual bow.
In another embodiment, a lightweight rangefinder comprises a high-resolution display and a digital camera.
In multiple embodiments, a display provides a relative aiming point that is displayed relative to a reference that shows the relative target size.
In some embodiments of a display with relative aiming point, the reference is a relative target icon.
In some embodiments of a display with relative aiming point, the reference is a reference image.
In some embodiments of a display with relative aiming point, the reference is a reference indicator, shown as reference lines.
In some embodiments of a display with relative aiming point, the display further comprises reference multiples.
In some embodiments of a display with relative aiming point, the reference is a user selectable image.
In some embodiments of a display with relative aiming point, the reference is a generic reference image.
Accordingly, it is an objective of the present invention to provide a display that provides information regarding a projectile trajectory.
Further, it is an objective of the present invention to provide a display that includes a relative target icon that is aligned to a relative target and is used to calibrate to any bow and arrow or other firearm.
Finally, it is an object of the present invention to provide a simple means of providing improved ballistic curve selection, without entering a ballistic group code or entering other information about the bow and arrow (such as peep height, arrow weight, arrow velocity) or about the bullet cartridge (such as bullet weight, muzzle velocity, ballistic coefficient).
Other aspects and advantages of the present invention will be apparent from the following detailed description of the preferred embodiments and the accompanying drawing figures.
Objects and Advantages
Accordingly, the present invention provides the following objects and advantages:
To provide a display that provides dynamic information regarding a projectile trajectory.
To provide a display that dynamically indicates clear shot to a ranged target.
To provide a display that dynamically indicates distances to obstacles in a projectile trajectory.
To provide a display that for a projectile trajectory to a ranged target shows a first path indicator, such as a twenty-yard indicator, above the cross hairs over the ranged target.
To provide a display showing a path indicator, such as a twenty-yard indicator, above the cross hairs over the ranged target, which is consistent with a range pin in an individual user's bow and bow sight (or other type of weapon sight).
To provide a display showing a path indicator, such as a twenty-yard indicator, above the cross hairs over the ranged target, which is consistent with a range pin in an individual user's bow and bow sight (or other type of weapon sight), which may be used as a aiming point, such as a twenty-yard aiming point for use with a twenty-yard bow sight pin.
To provide a display showing a plurality of path indicators above the cross hairs over the ranged target, which is consistent with range pins in an individual user's bow and bow sight (or other type of weapon sight).
To provide a simple way of calibrating a handheld rangefinder to be consistent with an individual user's bow and bow sight pins (or other type of weapon sight).
To provide a display that dynamically indicates a highest point in a projectile trajectory in relation to an image currently displayed based on target range and angle.
To provide a display that dynamically indicates a highest point in a projectile trajectory, as perceived by a user while shooting in relation to an image currently displayed.
To provide a lightweight rangefinder comprising a high-resolution display and a digital camera.
To provide an improved rangefinder which enable the user to visualize the projectile's trajectory creating confidence of a clear and safe shot.
To provide a display that provides a relative aiming point.
To provide a display that provides a relative target icon.
To provide a relative target icon in the display of range finding device that can be used to calibrate the range finding device to the ballistic curve for a specific firing device and specific projectile, such as a specific bow and arrow and a specific rifle and ammunition.
To provide a universal calibration method for any range finding device.
To provide a display that provides a relative aiming point relative to a reference target point.
To provide a display that provides a relative aiming point relative to a reference image.
To provide a display that provides a relative aiming point relative to a reference indicator.
To provide a display that provides a relative aiming point relative to a reference indicator and reference multiples.
To provide a display that provides dynamic information regarding a projectile trajectory.
To provide a digital display of a relative aiming point.
To provide a digital display of a relative aiming point and zoom control.
To provide an improved display of line of sight distance, horizontal distance, and angle.
To provide a relative target that can be used to determine the ballistic curve for a specific firing device and projectile, such as a specific bow and arrow or a specific rifle and ammunition.
BRIEF DESCRIPTION OF DRAWINGS
A preferred embodiment of the present invention is described in detail below with reference to the attached drawing figures, wherein:
FIG. 1A illustrates an archer with a bow with a bow sight;
FIG. 1B illustrates a rifle with a scope;
FIG. 2 illustrates exemplary details of a bow sight with multiple pins;
FIG. 3 is a block diagram of a rangefinder device;
FIG. 4 shows the appearance of an exemplary display within a device;
FIG. 5 is a rear perspective view of a digital rangefinder device;
FIG. 6 is a front perspective view of the rangefinder device of FIG. 5;
FIG. 7A is a diagram illustrating a first range to a target and an associated projectile trajectory;
FIG. 7B is a diagram illustrating a second range and an associated projectile trajectory to the target of FIG. 7A when the target is elevated, i.e. at a positive angle;
FIG. 7C is a diagram illustrating a second range and an associated projectile trajectory to the target when the target is at a lower elevation, i.e. at negative angle;
FIG. 7D is a diagram illustrating realistic target situation and an associated projectile trajectory to the target when multiple obstacles are present between the shooter and the target;
FIG. 8 is a diagram illustrating various angles and projectile trajectories relative to the device;
FIGS. 9A and 9B illustrate a display having dynamic path indicators, including embodiments with twenty-yard and forty-yard indicators;
FIG. 10 illustrates an exemplary projectile trajectory for targets at three different distances;
FIGS. 11A through 11C illustrate the steps in a method for calibrating a rangefinder device to a specific user's bow and bow sight;
FIGS. 11D and 11E illustrate an alternate method for calibrating a rangefinder device to a specific user's bow and bow sight using a calibration sheet.
FIG. 11F illustrates the user's perception of the maximum height of the projectile trajectory.
FIGS. 12A through 12C illustrate displays showing embodiments of a relative aiming point 1000 shown relative to a reference of a predetermine size, the reference shown by various means such as a reference image 1002, reference indicators 1006 lines, or a relative target icon 1120.
FIGS. 13A through 13D show embodiments of layout for the display segments;
FIG. 13E show an embodiment reference images;
FIGS. 14A through 14F illustrates an example of calibrating a range finding device to a specific bow and specific arrow using a relative target icon aligned with a prepared relative target;
FIGS. 15A through 15D illustrates an example of preparation of a relative target with a specific rifle and specific ammunition;
FIGS. 16A through 16F illustrates an example of calibrating a range finding device to a specific rifle and specific ammunition using a relative target icon aligned with a prepared relative target;
FIGS. 17A through 17D illustrates an alternate example of preparation of a relative target with a specific rifle and specific ammunition;
FIGS. 18A through 18F illustrates an alternate example of calibrating a range finding device to a specific rifle and specific ammunition using a relative target icon aligned with a prepared relative target;
FIGS. 19A through 19D illustrate the steps of the relative target preparation process with a specific rifle and specific ammunition; and
FIGS. 20A through 20F show the rifle ballistic calibration process used to calibrate the device.
FIG. 21 illustrates a high-resolution display showing a plurality of locations on a projectile trajectory adjusted for wind or weapon inertia.
The drawing figures do not limit the present invention to the specific embodiments disclosed and described herein. The drawings are not necessarily to scale, emphasis instead being placed upon clearly illustrating the principles of the invention.
REFERENCE NUMERALS IN DRAWINGS
1
a-c line of departure
2
a-c projectile trajectory
3
a-c, +, −line of sight
4 horizontal line
5 perception line
10 device
12 range sensor
14 tilt sensor
16 computing element
18 memory
20 housing
22 eyepiece
24 lens
25 digital camera
26 distal end
28 proximate end
30 display
31 high-resolution display
32 inputs
35 visor or shroud
100 archer or user
102 bow
104 arrow
110 bow sight
120 bow string sight
180 paper target
182 twenty-yard mark
184 forty-yard mark
190 calibration sheet
192 twenty-yard calibration mark
194 forty-yard calibration mark
198 calibration instructions
220 twenty-yard pin
240 forty-yard pin
260 sixty-yard pin
300 rifle
320 twenty-yard line
340 forty-yard line
420 twenty-yard projection
710 branch
720 bald eagle
730 bush
900 cross hairs
910 distance indicator
914 horizontal distance indicator
920 twenty-yard indicator
930 (selectable) path indicators
932 off screen indicator
940 forty-yard indicator
980 true aiming point
982 aiming point
990 angle and second range indicator
992 bow mode indicator
1000 relative aiming point
1002 reference image
1004 reference target
1006 reference indicator
1007
a-c reference multiple
1008 separator
1010 aiming point indicators
1012 too high indicator
1014 too low indicator
1020 enlarged target image
1042 sight in indicator
1044 distance text
1046 drop text
1048 target type indicators
1050 setup indicator
1052 antelope reference image
1054 deer reference image
1100 relative target
1102 target center
1110
a-d concentric square
1112 scale
1120
a-b relative target icon
1130
a-b shot mark
- P a-C, 0, 20, 40 point
- θa-C, 20, 40 angle
- T a-C, 20, 40, 60 target
- V a-b vertex
DETAILED DESCRIPTION OF THE INVENTION
The following detailed description of the invention references the accompanying drawings that illustrate specific embodiments in which the invention can be practiced. The embodiments are intended to describe aspects of the invention in sufficient detail to enable those skilled in the art to practice the invention. Other embodiments can be utilized, and changes can be made without departing from the scope of the present invention. The following detailed description is, therefore, not to be taken in a limiting sense. The scope of the present invention is defined only by the appended claims, along with the full scope of equivalents to which such claims are entitled.
Rangefinder Devices
A conventional rangefinder device 10 is shown in FIG. 4. FIG. 3 shows the internal components. The portable handheld housing 20 houses the range sensor 12, tilt sensor 14, computing element 16, and/or other desired elements such as the display 30, one or more inputs 32, eyepiece 22, lens 24, laser emitter, laser detector, etc.
The rangefinder device 10 comprise a housing 20, having an eyepiece 22 at the proximate end 28, a lens 24 and range sensor 12 at the distal end 26, and inputs 32 in various places on exterior.
Digital Rangefinder Devices
FIGS. 5 and 6 are rear and front perspective views, respectively, of a digital embodiment of rangefinder device 10.
In contrast to the conventional rangefinder, the housing 20 of a digital rangefinder device 10 contains a digital camera 25 that captures and digitizes video from the optical image through the lens 24 and contains a digital, high-resolution display 31. The video comprises a series of image frames. The computing element 16 (FIG. 3) processes the image frames, overlays each frame with various indicators, and displays the resulting image on the high-resolution display 31. Further, the high-resolution display 31 is controlled completely by the computing element 16 (FIG. 3) and need not display any of the optical image being captured; instead, the high-resolution display 31 may display setup menus, recorded video, or animations generated by the computing element 16 (FIG. 3).
The computing element 16 (FIG. 3) processes the image frames, overlays each frame with various indicators, and displays the resulting image on the high-resolution display 31. Further, the high-resolution display 31 is controlled completely by the computing element 16 (FIG. 3) and need not display any of the optical image being captured; instead, the high-resolution display 31 may display setup menus, recorded video, or animations generated by the computing element 16 (FIG. 3)
The eyepiece 22 may also be modified to accommodate viewing of the high-resolution display 31. In particular, the eyepiece 22 may be inset and be protected by a shroud 35.
In contrast to the conventional rangefinder housing 20 as shown in FIG. 4, the housing 20 of the digital rangefinder of FIGS. 5 and 6 is more compact, more lightweight, and easier to transport and use, due to removal of the end-to-end optics. For example, the length between the proximate end 28 and the distal end 26 is shown as less than about four inches. The width and height could be about two inches respectively.
High-Resolution Touch Screen Display
FIG. 5 also shows an exemplary touch screen display as an embodiment of the high-resolution display 31. The high-resolution display 31 displays the video image as digitally captured by the digital camera 25 or as simulated by the game software; the overlay information such as the twenty-yard indicator 920 and the forty-yard indicator 940, the cross hairs 900, the distance indicator 910, the mode indicators (e.g. 992 and 996), and the display inputs 34, shown as range button (34a) and fire button (34b). The display inputs 34 are virtual buttons that are tapped on a touch screen, or clicked on with a pointing device (or game controller). The input 32 is a physical button. Both inputs 32 and display inputs 34 provide input to the computing element 16 (FIG. 3).
Projectile Trajectories
FIG. 7A is a diagram illustrating a first range to a target T and an associated projectile trajectory 2. The rangefinder device 10 is show level such and the associated projectile trajectory leaves the weapon and enters the target at substantially the same true elevation (horizontal line 4).
The first range preferably represents a length of an imaginary line drawn between the device 10 and the target T, as shown in FIG. 7A, such as the number of feet, meters, yards, miles, etc., directly between the device 10 and the target T. Thus, the first range may correspond to a line of sight (LOS) 3 between the device 10 and the target T.
FIG. 7B is a diagram illustrating a second range and an associated projectile trajectory 2 to the target T when the target T is elevated, i.e. is at a positive angle. The first range is the sensed range along the line of sight 3. The second range is the true horizontal distance to the target T, as measured along the horizontal line 4. A third range is the true horizontal distance, as measured along the horizontal line 4, to the projectile trajectory 2 intercept. Half of the third range is the x-axis distance to the vertex V of the projectile trajectory 2. The second range is determined by multiplying the first range by the cosine of the angle.
FIG. 7C is a diagram illustrating a second range and an associated projectile trajectory 2 to the target T when the target T is at a lower elevation, i.e. is at a negative angle. The first range is the sensed range along the line of sight 3. The second range is the true horizontal distance to the target T, as measured along the horizontal line 4. The third range is the true horizontal distance, as measured along the horizontal line 4, to the projectile trajectory 2 intercept. Half of the third range is the x-axis distance to the vertex V of the projectile trajectory 2.
In situations where the angle is non-zero, such as when the target T is positioned above (FIG. 7B) or below (FIG. 7C) the device 10, the parabolic movement of the projectile affects the range calculation, such that the projectile may have to travel a longer or shorter distance to reach the target T. Thus, the second range provides an accurate representation to the user of the flat-ground distance the projectile must travel to intersect the target T.
FIG. 7D is a diagram illustrating an exemplary realistic target situation (similar to the one shown in FIG. 6) and an associated projectile trajectory 2 to the target T when multiple obstacles are present between the shooter and the target. A tree with a branch 710 is show at about twenty yards. A bald eagle 720 is shown in a second tree at about forty yards. Also at forty yards is a bush 730. These obstacles conventionally would cause a lack of confidence and concern regarding the accuracy, effectiveness, safety, ethics, and legality of the anticipated shot. Because the bush 730 is in the line of sight 3, some users with little understanding of parabolic trajectories would not believe they could make the shot. Other users, who understand that the projectile trajectory is parabolic, know that the path of the trajectory goes above the line of sight 3 (see also FIG. 8). These more understanding shooters may be concerned that the projectile would hit the branch 710 or the bald eagle 720. The clear shot technology disclosed herein provides several solutions to address these concerns.
FIGS. 7A through 7C are shown with an exemplary projectile trajectory 2 based on a parabola with an A value of −0.005.
FIG. 8 is a diagram illustrating various angles and projectile trajectories relative to the device. The device 10 preferably comprises a tilt sensor 14. The tilt sensor 14 is operable to determine the angle to the target T from the device 10 relative to the horizontal. Thus, as shown in FIGS. 7A and 8, if the device 10 and the target T are both positioned on a flat surface having no slope, the angle would be zero. As shown in FIGS. 7B and 8, if the device 10 is positioned below the target T the slope between the device 10 and the target T is positive, the angle would be positive. Conversely, as shown in FIGS. 7C and 8, if the device 10 is positioned above the target T, such that the slope between the device 10 and the target T is negative, the angle would be negative.
Clear Shot Displays
FIGS. 9A and 9B illustrate a display having dynamic path indicators 930 (or trajectory path indicators). The path indicators 930 each show a point in the trajectory path at an intermediate range. A display aspect of the present invention includes embodiments with twenty-yard indicators 920 and forty-yard indicators 940.
FIG. 9A shows the active display elements when the target T (not shown for clarity) is ranged at twenty yards. The display shows the cross hairs 900 (shown here with a center circle) which are placed on the target T. The display 30 dynamically shows that the range is twenty yards in the distance indicator 910. Because of the short distance, the projectile trajectory is close to linear so no additional indication is generally needed.
In the figures the symbols used for the various indicators are exemplary and other shapes or styles of indicators could be used. For example, the cross hairs 900 are shown with a center circle, but other styles such as intersecting lines, a solid center dot, and so forth could be used. The distance indicator 910 is shown having using seven segments for the digits, but other shapes of styles could be used. Positions are also exemplary.
FIG. 9B shows the active display elements when the target T (not shown for clarity) is ranged at forty yards. The display 30 shows the cross hairs 900 (show here with a center circle) which are placed on the target T. The display 30 dynamically shows that the range is forty yards in the distance indicator 910. The display 30 also dynamically illuminates a twenty-yard indicator 920. The twenty-yard indicator 920 shows a point in the projectile trajectory 2 path (e.g. FIG. 7D) at twenty yards relative to the optical image (not shown for clarity) upon which the display 30 is superimposed. The twenty-yard indicator 920 informs the user where the projectile will be at twenty yards distance. Because the twenty-yard indicator 920 shows an intermediate trajectory path point where the arrow will be at twenty yards distance, the twenty-yard indicator 920 is a twenty-yard pin aiming point 982. A bow hunter can place the twenty-yard pin 220 of the bow sight 110 on the same visual spot indicated, for example as shown in FIG. 11A, and the arrow will hit the target T at the cross hairs 900.
The target ranges of twenty, forty, and sixty yards are exemplary and chosen to simplify the description of the figures. However, the range displayed on the distance indicator 910 is the actual line of sight 3 range to the target T. If the actual range were twenty-eight yards, then the distance indicator 910 would show twenty-eight yards and the twenty-yard indicator 920 would be shown closer to the cross hairs 900 than it is shown in FIG. 9B. Further, if the actual range were thirty-seven yards, then the distance indicator 910 would show thirty-seven yards and the twenty-yard indicator 920 would be shown farther from the cross hairs 900 than it is shown in FIG. 9B. This highlights the dynamic nature of the illumination of the path indicators (e.g. 920 or 940).
The examples herein generally use yards as the unit of measure. The invention is not limited to yards, but could also be set using feet, meters, kilometers, miles, and so forth.
In some bow embodiments the display 30 or device 10 is calibrated such that the location of the twenty-yard indicator 920 matches the relative position of the twenty-yard pin 220 on the individual user's bow and bow sight 110 (see FIGS. 1 and 2).
In other bow embodiments the display 30 or device 10 is calibrated such that both locations of the twenty-yard indicator 920 and the forty-yard indicator 940 match the relative position of the twenty-yard pin 220 and forty-yard pin 240, respectively, on the individual user's bow and bow sight 110 (see FIGS. 1 and 2)
Methods for Determining and Displaying a Clear Shot
Some method aspects of the present invention will be explained with specific reference to FIG. 10.
FIG. 10 illustrates an exemplary projectile trajectory for targets at three different distances. As discussed above, it is well known that a projectile trajectory follows a parabolic or ballistic trajectory. The parabolic curve is generally determined by the force of gravity on the projectile. Further, air drag reduces the projectiles velocity and affects the curve. As disclosed herein, the information to accurately identify the trajectory for a given weapon and projectile combination may be determined by information entered during calibration. Additionally, as will be discussed later the device 10 can be calibrated to match the specific trajectory of an individual's bow and bow sight which has been calibrated a specific individual to match their individual strength, form, and bow handling.
Once the trajectory is known for a particular projectile, the curve is represented in the device by a mathematical formula, such that any point along the projectile trajectory may be calculated. FIG. 10 shows three exemplary points, namely point Pa, point Pb, and point Pc. A shot taken at angle A (shown as theta a) along line of departure 1a will travel along projectile trajectory segment 2a until it intercepts target Ta (shown as T20) at a horizontal distance of twenty yards along line of sight 3a. A shot taken at angle B (shown as theta b) along line of departure 1b will travel along projectile trajectory segment 2b until it intercepts target Tb (shown as T40) at a horizontal distance of forty yards along line of sight 3b. A shot taken at angle C (shown a theta c) along line of departure 1c will travel along projectile trajectory segment 2c until it intercepts target Tc (shown as T60) at a horizontal distance of sixty yards along line of sight 3c.
When FIGS. 7B and 7C are considered, FIG. 10 also reveals that a shot could be taken from point Pb and intersect target Ta (shown as T20) at a horizontal distance (second range) of thirty yards and a positive angle line of sight 3+. Further, a shot could be taken from point B and intersect target Tc (shown as T60) at a horizontal distance (second range) of fifty yards and a negative angle line of sight 3−. According, once the projectile trajectory is known any angle of line of sight 3 and sensed range (first range) can be used to calculate the horizontal distance (second range) to any point in the projectile trajectory.
Line of departure 1c is a parabolic tangent of the projectile trajectory 2c that intersects the parabola at point P0 at (0, 0).
Steps for Calibrating a Device to a Specific User's Bow and Bow Sight
FIGS. 11A through 11C illustrates the steps in a method for calibrating a rangefinder device 10 to a specific user's bow 102 and bow sight 110.
Typically, a user will use a paper target 180 at known distances to set one or more bow sight pins, such as twenty-yard pin 220, forty-yard pin 240, sixty-yard pin 260 (FIG. 2).
The following steps may be used to calibrate the device 10 to correspond to a specific user's bow sight 110.
As shown in FIG. 11A, the user 100, places an exemplary paper target 180, shown as a conventional archery target with concentric rings, at sixty yards. The user 100 then aims the bow 102 placing the sixty-yard pin 260 over the center of the paper target 180. The user observes where the twenty-yard pin 220 and the forty-yard pin 240 appear on the paper target 180.
Next, as shown in FIG. 11B the user 100 (or an assistant) places a mark where each pin appeared at sixty yards. For example, a twenty-yard mark 182 and a forty-yard mark 184, respectively, are shown on the target in FIG. 11B.
Next, as shown in FIG. 11C, the user 100 holds the device 10 at the same sixty yard distance and enters bow calibration mode. The distance indicator 910 should read sixty yards. In some embodiments, the device 10 will prompt the user 100 to position the twenty-yard indicator 920 over the twenty-yard mark 182. After the prompt, each time the user 100 operates an input 32 the next one of the plurality of selectable path indicators 930 will be illuminated. The user 100 will continue to adjust the position of the illuminated selectable path indicators 930 until it matches the twenty-yard mark 182 on the paper target 180. Once the first path indicator is calibrated, then the device 10 prompts the user 100 to position the next path indicator, for example, the forty-yard indicator 940 over the forty-yard mark 184, in a similar manner, until all the pins have been calibrated.
Based on this calibration information the device 10 can determine the parabolic curve (projectile trajectory) applicable to the user's specific bow 102 and bow sight 110.
In a simpler embodiment, corresponding to FIGS. 9A and 9B only, the device 10 operates with only a single path indicator, such as only the twenty-yard indicator 920. Correspondingly, an alternate calibration method is simpler as well. In this simpler embodiment, the paper target 180 is positioned at forty yards. The distance indicator 910 should read forty yards. The paper target is marked only with the twenty-yard mark 182. Next, the device 10 will prompt the user 100 to position the twenty-yard indicator 920 over the twenty-yard mark 182, whereupon the calibration is complete.
Calibration Sheet for Calibrating a Device to a Specific User's Bow and Bow Sight
FIGS. 11D and 11E illustrates an alternate method for calibrating a rangefinder device 10 to a specific user's bow 102 and bow sight 110 using a calibration sheet 190.
When calibration is done in the field with a target as described above, the user typically has a bow, an arrow, and a target that can be shot to confirm the calibration with an actual arrow. However, field verification is not required. Calibration can be performed in a smaller space, even indoors, using only the rangefinder device 10, the bow 102 with a bow sight 110, and a calibration sheet 190. This assumes that the user has already adjusted the bow sight 110 at known distances to set one or more bow sight pins, such as twenty-yard pin 220, forty-yard pin 240, sixty-yard pin 260 (FIG. 2).
The steps are similar to those above as described regarding the simpler embodiment with only the twenty-yard indicator 920, except that the calibration sheet 190 is already marked and the user moves the bow 102 and the rangefinder relative to the calibration sheet 190.
FIG. 11D shows a calibration sheet 190 having a twenty-yard calibration mark 192, a forty-yard calibration mark 194, and calibration instructions 198. The calibration sheet 190 can be a standard 8.5×11 sheet of paper or smaller. The twenty-yard calibration mark 192 in this example is shown labeled “20 PIN” and the forty-yard calibration mark 194 is labeled “40 PIN”. Optionally, calibration instructions 198 can be provided on the calibration sheet 190. Example instructions could read, “ClearShot™Calibration with 20 and 40 Yard Bow Sight Pins: Calibration for your specific bow using this method requires you to stand the correct distance from this calibration sheet. 1) Start about 10 yards from this calibration sheet. 2) In the shooting position, move forward or backward until your 20 and 40 yard bow sight pins match the 20 and 40 pin marks on this calibration sheet. 3) Put the rangefinder in calibration mode. Align the rangefinder's cross hairs with the cross hairs mark labeled ‘40 PIN’ on this calibration sheet. Adjust the rangefinder's ClearShot™ indicator to match the ‘20 PIN’ mark on this calibration sheet.”
FIG. 11E illustrates how the exemplary trajectories and angles of FIG. 10 are used to dynamically determine the display locations for the path indicators 930, such as the twenty-yard indicator 920.
FIG. 11E illustrates the projectile trajectory segment 2b from FIG. 12 transposed such that the departure point Pb is aligned at zero on the range scale (x-axis), common point P0. The horizontal line of sight 3 is the now the x-axis. In this example, the x-axis has unit of yards. The y-axis on the left also has units of yards.
FIG. 11E also shows dashed lines, twenty-yard projection 420, showing the angle from the point of departure to the intersection of a vertical twenty-yard line 320 (at point P20). Further, superimposed on the curve and angle is a perspective view of a section of the display 30 showing how the location of the path indicator is determined. The cross hairs 900 are shown where the line of sight 3 (now x-axis) is projected on the display 30. The distance indicator 910 shows the sensed range, for example, in this case 40 yards. One of the plurality of selectable path indicators 930 (FIG. 13B and FIG. 13D) is illuminated based on where the twenty-yard projection 420 line corresponds to the relative position on the display 30. The y-axis on the right relates to the scale of the display 30 also has units of millimeters.
The projectile trajectory 2 will vary based on many parameters related to the weapon, such a bow type, the projectile, the user, and the range and angle to the target. In the example shown in FIG. 11E, the projectile trajectory 2b has a vertex Vb. The origin, point P0 is at (0,0). Angle θ20 is 26.6 degrees. The exemplary conversion factor from the real world (left y-axis) to the scale of the display 30 chip (right y-axis) is 5 yards=1 millimeter. Once angle θ20 is calculated, the corresponding one of the plurality of selectable path indicators 930 is turned on for the twenty-yard indicator 920 (e.g. 3 millimeters).
The line of departure 1b (FIG. 12) is a parabolic tangent of the projectile trajectory 2b that intersects the parabola at point P0 at (0, 0). The slope of the parabolic tangent 1b, or mb, is found by calculation the tangent, namely opposite over adjacent. The equation for line of departure 1b is y=m*x+b. The angle of each line is found by using the inverse tangent (arctan or tan−1), function.
The tangent of the twenty-yard projection 420 line is 30/60 or 0.5 and θb=arctan(0.5) =26.6 degrees.
Using another example of the 60-yard target T60, FIG. 10, the values for the parabolic equations for projectile trajectory 2c are:
- h=30
- k=11.25
- A=−0.0125
- B=0.75
- C=0
The standard form equation is:
The vertex form equation is:
The computing element 16 (FIG. 3) uses a mathematical model representation of the curve, angle and line shown in FIGS. 10 and/or 11E in memory 18, calculates the relative distance from the cross hairs 900 to the computed point that the twenty-yard projection 420 would appear on the computed representation (or model), and uses the relative distance to selectively illuminate the appropriate one of the plurality of selectable path indicators 930. Thus, an aspect of the invention is that the path indicators 930, such as the twenty-yard indicator 920, is displayed dynamically based on the projectile trajectory 2 and sensed range, and correspond to the relative distance above of the target T and obstacles (e.g. 710, 720, 730) upon which the display is superimposed. Further, in bow mode, the path indicators correspond the individual user's bow 102 and bow sight 110 (FIG. 1).
FIG. 11E shows the 40-yard curve 2b with the calibration sheet 190. P0 is the same as Pb in FIG. 10. FIG. 11E shows how the angle θ20 for a twenty-yard indicator 920 is the same on a 40-yard field target as it is on the calibration sheet 190 at about ten yards. In one embodiment of a calibration sheet the twenty-yard calibration mark 192 and the forty-yard calibration mark 194 are pre-marked about 4.25 inches apart. The distance between the marks is arbitrary but 4.25 inches corresponds to a calibration sheet distance of about ten yards for most bows, which is short enough to be easy to work with (even indoors), and which is far enough for reasonable calibration accuracy. The same sheet would also work if the calibration units were meters instead of yards.
As shown in FIG. 11E angle θ20 for the specific's bow twenty-yard pin 220 and forty-yard pin 240 would be visualized the same at 40 yards using twenty-yard projection 420 as it would at any intermediate point where the calibration sheet may be placed relative to the rangefinder device 10 (at zero). Thus, by positioning the user's eye relative to the calibration sheet marks to create this angle θ20 will allow the user the place the rangefinder device 10 in the exact same point and position the twenty-yard indicator 920 to the same visual angle in calibration mode. Slower bows or arrows will have a higher projectile trajectory and thus the twenty-yard indicator 920 will need to be adjusted higher so the user will correctly move closer to the calibration sheet than with faster bows or arrows.
The following steps may be used to calibrate the device 10 to correspond to a specific user's bow sight 110 using the calibration sheet 190.
The user 100 places an exemplary calibration sheet 190 on a wall or door. The user 100 starts out standing about ten yards away from the calibration sheet 190 with the bow 102 and the rangefinder device 10. The user 100 then aims the bow 102 placing the forty-yard pin 240 over the forty-yard calibration mark 194. The user moves forward or backward until the twenty-yard pin 220 matches twenty-yard calibration mark 192 (while still aiming the forty-yard pin 240 at the forty-yard calibration mark 194). Without moving the user's eye position relative to the calibration sheet 190, the user 100 brings the rangefinder device 10 to the user's eye, aims the rangefinder device 10 placing the cross hairs 900 over the forty-yard calibration mark 194, and, while in 40-yard calibration mode, adjusts the twenty-yard indicator 920 to match the twenty-yard calibration mark 192. In some rangefinder devices 10 the user 100 could adjust the twenty-yard indicator 920 by pressing one or more buttons. In a high-resolution rangefinder with a touch screen, the user could simply tap the correct height on the high-resolution display 31.
In an embodiment of the rangefinder device 10 with 60-yard calibration mode, an alternate calibration sheet 190 uses a sixty-yard calibration mark 196 instead of a forty-yard calibration mark 194. With this embodiment the user aims the bow 102 using the sixty-yard pin 260 and moves forward or backward until the twenty-yard pin 220 matches twenty-yard calibration mark 192. The user 100 brings the rangefinder device 10 to the user's eye, aims the rangefinder device 10 placing the cross hairs 900 over the sixty-yard calibration mark 196, and, while in 60-yard calibration mode, adjusts the twenty-yard indicator 920 to match the twenty-yard calibration mark 192. This 60-yard calibration mode allows for more precise calibration for faster bows and arrows. This alternate calibration sheet 190 for 60-yard calibration mode could be printed on the back of the calibration sheet 190 for 40-yard calibration mode.
Further, FIG. 11E further shows that any two points at a fixed distance could be used, for example in 40-yard calibration, to calibrate the rangefinder device 10. For example, if the calibration sheet 190 were lost or not available, the user 100 could pick two points on a wall or tree or other objects that correspond to twenty-yard pin 220 and the forty-yard pin 240. The user 100 aims the bow 102 placing the forty-yard pin 240 over the lower point. The user moves forward or backward until the twenty-yard pin 220 matches higher point. Without moving the user's eye position relative to the two points, the user 100 brings the rangefinder device 10 to the user's eye, aims the rangefinder device 10 placing the cross hairs 900 over the lower point, and, while in 40-yard calibration mode, adjusts the twenty-yard indicator 920 to match the higher point.
Reverse Application
The method by which the path indicators, such as the twenty-yard indicator 920, are used to calibrate the device 10 (by determining the corresponding projectile trajectory 2) may be understood by reference to FIG. 11E. Essentially, the method used to determine the location of the path indicators based on the projectile trajectory 2 is reversed.
The calibrated location, for example, the twenty-yard indicator 920 indicates the height on the millimeter y-axis of the corresponding project lines, for example, the twenty-yard projection 420 line. The projection line is modeled starting at the origin point P0 (0, 0) and ending at the projected point (e.g. 920) at the 40-yard x-axis. The intersection point, P20, is then determined where the twenty-yard projection 420 line cross the twenty-yard line 320. The origin point P0 (0, 0), and the twenty-yard intersection point P20 (20, y20) are then used to calculate the parabola. Thus, the projectile trajectory 2 that corresponds to an individual user's bow 102 and bow sight 110 is determined.
In the example shown in FIG. 11E, the twenty-yard indicator 920 is calibrated at three millimeters (on the display y-axis). This corresponds to twenty yards based on the focal range conversion. The tangent is 20/40 or 0.5. The inverse tangent function provides the angle of the twenty-yard projection 420 line, θ20 arctan (0.5) equals 26.6 degrees. This angle can then be used to calculate the twenty-yard intersection point P20. Once P20 is known, the corresponding parabolic equation is determined using y20 in the equation explained below.
Alternatively, in yet another calibration method, the user 100 can compare the bow sight pins (220, 240, 260) to a printed set of common settings and then enter associated values or code to provide the device with corresponding projectile trajectory 2 data. The code can be used to perform a lookup of the projectile trajectory 2.
In yet another calibration embodiment, the user 100 measures the distance between the twenty-yard pin 220 and the forty-yard pin 240, and the distance between the forty-yard pin 240 and the sixty-yard pin 260 and enters those values into the device 10. The device 10 uses those values, in a method similar to one described above, to calculate the corresponding projectile trajectory 2, or to lookup the projectile trajectory 2 in a table stored in memory 18.
Single Point Sufficient
Conventionally, it is understood that to determine a parabola three points must be known. This is because in either the standard form or the vertex form there are three variables in addition to the x and y values for the points (namely, A, B, and C in standard form or A, h, and k in vertex form). However, with the model, methods, and devices disclosed herein, only one value, specifically the y20, is needed to determine the parabola.
In reference to the model shown in FIG. 11E, and the calibration methods discussed in reference to FIGS. 11A through 11C, the origin point Po is always (0, 0) and the T point is always (60, 0). Using these values for x0, y0, y60 and y60 two of the unknowns may be solved with A remaining as the only unknown. The x value of the twenty-yard intersection point P20 (20, y20) is always 20. Thus, only a single equation with a single value, y20 is needed to determine all the other variables in the standard or vertex form of parabolic equations.
The single equation to find A based on y20 is as follows:
Once A is known, the other equations are:
Two Points Provide Air Drag Adjustment
In our model, if there were no air drag, height of the projectile trajectory 2 would be the same at both the twenty-yard intersection point P20 (20, y20) and the forty-yard intersection point P40 (40, y40), Y20 equals y40. If y20 does not equal y40, the difference between y20 and y40 provided an indication of the air drag impact on the projectile trajectory 2. Thus, if the user provides a second point, the device 10 can determine the effect of air drag on the projectile and adjust the projectile trajectory 2 and clear shot indications according.
Air drag calculations are very complex and a table look up is used to apply the air drag adjustments to the true parabolic values. In an embodiment which uses a second calibration point the difference between y20 and y40 is used with other projectile data to select a table of adjustment values which are then applied to the true parabolic values to map out the adjusted projectile trajectory 2.
In a smart rangefinder embodiment described below, a dynamic table of air drag values is filled in based on analysis of an actual video of an individual projectile shot in a known environment, such as the sixty yard paper target 180 of FIG. 11C.
User's Perception of the Highest Point in the Projectile Trajectory
FIG. 11F is a simplified, enlarged version of FIG. 11E with the addition of a user 100, a bow 102, a perception line 5, and line of departure 1b. The other elements are the same as described in reference to FIG. 11E. The perception line 5 is the line from the user's eye to the point seen over the target T as indicated by the twenty-yard indicator 920. The perception line 5 is different than the line of sight 3b, which is the line from the arrow 104 or the rangefinder device 10 to the target T (e.g. see FIGS. 7A through 7D). The bow 102 and arrow 104 are aimed using the twenty-yard indicator 920, which places the arrow 104 on line of departure 1b. The arrow will follow the projectile trajectory 2b and hit the target T (not shown) visualized in the center of the cross hairs 900. The true maximum height will be at vertex Vb. However, because user's eye is higher than the arrow 104, FIG. 11F shows that the arrow will appear to raise up to the perception line 5 (about the perceived height of the twenty-yard indicator 920) and then, after twenty-yards, appear to drop down quickly into the target. Although FIG. 11F only illustrates the forty-yard case, at other distances such as sixty yards and eighty yards, generally the twenty-yard indicator 920, which will be higher, still is perceived to the be maximum height of the projectile trajectory. Thus, any object that appears to be close to the twenty-yard indicator 920, along perception line 5, during the first twenty yards will likely be an obstacle and make the shot not a clear shot. Further, any object that appears to be above the twenty-yard indicator 920 at any point will not be an obstacle. Thus, the twenty-yard indicator 920 (and substantially similarly a twenty-meter indicator) provides both an aiming point 982 (FIG. 9A) and an indication of what the user 100 will perceive as the highest point in the projectile trajectory 2b allowing the user 100 to determine whether or not an obstacle is in the projectile trajectory 2b.
Enhanced ClearShot Technology for Rifle and Military Markets
Various embodiments of the inventions discussed above have been incorporated in Bushnell's The Truth with ClearShot™ laser rangefinder, Leupold's RX-FullDraw 4, RX-FullDraw 5, and RX-1400i TBR/W laser range finders. These products have been very successful and has been critically acclaimed and well received by the industry, especially for bow hunting.
However, the layout of the display, e.g., see FIG. 9B, with for example, a 4× focal magnification is limited to relative slow projectiles such as arrows and black powder rifle balls (e.g., less than 400 feet per second), which are typically shot at targets less than 80 yards away.
Modern rifles with high-performance cartridge bullets and other military projectiles such as tank guns can travel 10 to 20 times faster, and can be shot at targets that are hundreds or thousands of yards away. These higher velocity projectiles have a flatter projectile trajectory and the aiming point is closer to the target.
What is needed for higher velocity projectiles, such as those in the rifle hunting, law enforcement, and military industries, is a means for showing a relative aiming point using a reference representing an enlarged view of the target.
RELATIVE AIMING POINT
The following sections describe various enhancements to the clear shot technology discussed above, which provide a relative aiming point to meet the needs of users of higher velocity projectiles.
Relative Aiming Point Relative to a Reference of a Predetermined Height
FIGS. 12A through 12F illustrate displays showing embodiments of a relative aiming point 1000 shown relative to a reference of a predetermine size, the reference shown by various means such as a reference image 1002, reference indicators 1006 lines, a generic reference 1005, or a relative target icon 1120.
FIG. 12A illustrates a display 30 showing an embodiment of a relative aiming point 1000 shown relative to a reference of a predetermine size. The display 30 shows the active display elements when a target T is ranged at four hundred yards. Note that the target T is visually much smaller than a deer would be when ranged at sixty yards. The display 30 shows cross hairs 900 (shown here with a center circle) which are placed on the target T. The display 30 dynamically shows that the horizontal range is four hundred yards in a horizontal distance indicator 914.
The target T and the target's surroundings are visually shown at a known focal magnification (such as 4× or 6× based on the lens 24 of the device 10). The display elements are superimposed over, or displayed over, the visual image.
In this embodiment, the reference is shown as a reference image 1002, for example as a generic deer with a chest height of 18 inches. The chest height is measured from the belly to the top of the back. The reference image 1002, such as an image of a deer, can be selected by the user in settings. The user can also set the chest height for the deer, based on predetermined sizes for typical deer, such as 14 inches, 16 inches, or 18 inches.
This embodiment also shows reference target 1004 placed in the reference image 1002.
Operation of the Relative Aiming Point
FIG. 12A shows that the optical image of the deer, target T, at four hundred yards is very small. The indicators as shown in the bow mode embodiment in FIG. 4 do not have high enough precision to be useful for a long-range target T, such as at four hundred yards. This enhancement provides a rifle mode which can be combined with the bow mode in the same device, or which can be implemented independently in rangefinders used in the rifle and military markets.
Initially, the user sets up the rangefinder device 10 by selecting rifle mode; calibrating the device to the zero of the rifle sight or scope; selecting a reference type (such as the deer references image 1002 as shown); and selecting a reference size. See additional discussion below regarding settings. See discussion regarding FIGS. 13A through 20F regarding a currently preferred relative target method of entering ballistic curve information (instead of entering a ballistic code).
A novel aspect of the present invention is that the user does not need to enter a ballistic code of specific ammunition, because a ballistic group and corresponding lookup table is determined based on the calibration methods described herein.
When the user ranges a target T, the rangefinder device 10 determines a line of sight 3 distance (e.g. the laser distance), determines an angle (using a tilt sensor or accelerometer), and then uses the line of sight distance and the angle to determine a horizontal 4 distance to the target T, which is displayed in the horizontal distance indicator 914.
Next, the device 10 determines the projectile trajectory 2. In rifle mode the shape of the parabola is determined by the ballistic code entered in settings 1034. The values for the projectile trajectory is determined from the ballistic code in a lookup table stored in the device 10, or, preferably, real ballistic curve information is used. For example, a 0.270 Winchester, zeroed at 100 yards, has about a 10-inch drop at 285 yards.
After calculating the aiming point 982, in relation to the target T, the reference image 1002 is displayed, and the relative aiming point 1000 is displayed relative to the reference using the predetermined reference height, for example 18 inches.
In the exemplary embodiment shown in FIG. 12A, the deer has a predetermined chest height of 18 inches as set by the user. The relative aiming point 1000 is determined to be about 21 inches based on the ballistic code and the 100 yard zero settings, and based on the horizontal distance of 400 yards determined by the rangefinder device 10.
In the FIG. 12A embodiment, the reference image 1002 has a fixed size and position. The relative aiming point 1000 is displayed dynamically based on the measured horizontal distance using the current ballistic, zero, and reference size settings. If the horizontal distance is less than the zero setting, the relative aiming point 1000 is displayed below the reference target 1004. If the horizontal distance is the same as the zero setting, the relative aiming point 1000 is the reference target 1004. If the horizontal distance is greater that the zero setting the relative aiming point 1000 is displayed above the reference target 1004.
Relative Aiming Point Relative to Reference Lines
FIG. 12B illustrates a display 30 showing an embodiment of a relative aiming point 1000 shown relative to a reference indicator 1006 shown as reference lines. Like FIG. 12A, the display 30 shows cross hairs 900 and dynamically shows the horizontal range in a horizontal distance indicator 914.
In this embodiment, the reference is shown as the reference indicator 1006 shown as reference lines.
This embodiment also shows reference target 1004 centered in the reference indicator 1006.
In this embodiment, the reference indicator 1006 has a fixed size and position. The relative aiming point 1000 is displayed dynamically based on the measured horizontal distance using the current ballistic, zero, and reference size settings.
Relative Aiming Point Relative to Relative Target Icon
FIG. 12F illustrates a display 30 showing an embodiment of a relative aiming point 1000 shown relative to a novel relative target icon 1120. Like FIG. 12A, the display 30 shows cross hairs 900 and dynamically shows the horizontal range in a horizontal distance indicator 914.
In this embodiment, the novel relative target icon 1120 has a fixed height and position. The relative aiming point 1000 is displayed dynamically based on the measured horizontal distance using the current ballistic, zero, and reference size settings.
The relative target icon 1120 represents a 20-inch by 20-inch relative target 1100 (see FIG. 14A) in Imperial “yard” mode, where the target height is 20 inches. The relative target icon 1120 represents a 50 cm by 50 cm relative target 1100 (see FIG. 14B) in metric “meter” mode, where the target height is 50 cm.
In this embodiment, the reference is shown as the relative target icon 1120. This relative target icon 1120 can be used for a variety of types of target without having to modify the target height setting. The advantage of the novel relative target icon 1120 over the other embodiments can be understood by the following examples.
When the distances are shown in yards, the relative target icon 1120 corresponds to 20-inch by 20-inch relative target 1100. As discussed below in relation to FIG. 14A, the markings on the relative target 1100 comprise of four concentric squares 1110 (a-d) having sides measuring 20 inches, 15 inches, 10 inches, and 5 inches, respectively. The relative target icon 1120 comprises display segment elements that correspond to the four concentric squares 1110 (a-d) of the relative target 1100. If the current target T is a mule deer having a chest height of 18 inches which is between 20inches and 15 inches, the user would use the white band between the outer two concentric squares 1100a and 1100b to visualize the reference to the 18-inch mule deer chest and then used the relative aiming point 1000 to visualize where to aim. If an antelope, having a 15-inch chest height, comes into view, the user would use the 15-inch concentric square 1100b to visualize the reference to the 15-inch antelope chest and then used the relative aiming point 1000 to visualize where to aim. If a prairie dog, having a 10-inch body height, comes into view, the user would use the 10-inch concentric square 1100c to visualize the reference to the 10-inch prairie dog body and then used the relative aiming point 1000 to visualize where to aim. If no living targets show up for the hunt, a tin can having a height of about 5 inches, can be visualized by using the 5-inch concentric square 1100d to visualize the reference to the tin can and then used the relative aiming point 1000 to visualize where to aim.
In a military example, if a terrorist, having a 20-inch chest height, comes into view, the user, a warfighter, would use the 20-inch concentric square 1100a to visualize the reference to the terrorist's chest and then used the relative aiming point 1000 to visualize where to aim. If only an enemy's head, about 9 inches high, is seen above a wall, the warfighter would use the 10-inch concentric squares 1100c to visualize the reference to the 9 inch head and then used the relative aiming point 1000 to visualize where to aim.
In this example, the operation is as follows: when the user 100 presses the range input 32 button on the range finding device 10, the cross hairs 900 are selective illuminated allowing the user aim the range sensor at the target T, the range finding device 10 uses the distance from the range sensor 12 and the angle from the tilt sensor 14 to determine the horizontal distance to the target which is displayed in the horizontal distance indicator 914, shown as 346 yards. As visualized in FIG. 12F, the resolution of the display 30 is inadequate to show an absolute aiming point 982 in relation to the actual visualized image of the target T. Compare this to the 40-yard example shown in FIG. 4, where the selectable path indicators 930 of layout of FIG. 13B (or FIG. 13D) are adequate to show an absolute aiming point 982, or the 60-yard example shown in FIG. 5 where the digital display 31 has the adequate resolution to show an absolute aiming point 982.
Display Layouts for Relative Aiming Point
FIGS. 13A through 13E show embodiments of layout for the display segments or display elements which are superimposed on the visual image of the target and the target's surroundings.
FIG. 13A shows an embodiment of a layout for the display segments. An exemplary display 30 comprises segments forming cross hairs 900, a horizontal distance indicator 914, a reference target 1004, a reference indicator 1006, and a plurality of selectable aiming point indicators 1010.
The cross hairs 900 are positioned centrally in the display 30. The horizontal distance indicator 914 is positioned peripherally, shown near the left edge of the display 30. The reference indicator 1006 is positioned peripherally in the display 30, shown near the right edge of the display 30. The aiming point indicators 1010 are also positioned peripherally and centered on the reference indicator 1006.
The plurality of selectable aiming point indicators 1010 are dynamically and selectively illuminated to provide the relative aiming point 1000.
In other embodiments, two or more reference images 1002 or a generic reference 1005 could also be added to the layout, each as a single segment, which is dynamically and selectively illuminated to provide the reference based on the settings. See FIGS. 13C and 13E.
FIG. 13B shows an embodiment of a more robust, hybrid layout for the display segments. An exemplary display 30 comprises segments forming cross hairs 900, a horizontal distance indicator 914, selectable path indicators 930, an off screen indicator 932, angle and second range indicator 990, a reference target 1004, a reference indicator 1006, reference multiples 1007a-c, a separator 1008, and a plurality of selectable aiming point indicators 1010.
The cross hairs 900 are positioned centrally in the display 30. The selectable path indicators 930 and off screen indicator 932 are centered on the cross hairs 900. The horizontal distance indicator 914 and angle and second range indicator 990 are positioned peripherally, shown near the left edge of the display 30. The reference indicator 1006 is positioned peripherally in the display 30, shown near the right edge of the display 30. The aiming point indicators 1010 are also positioned peripherally and centered on the reference indicator 1006. The reference multiples 1007a-c are also positioned relative to the reference indicator 1006.
The separator 1008 may be useful to help the user visually distinguish, or separate, the visual image of the target and the relative aiming point portions of the display 30.
In hybrid embodiments, the selectable path indicators 930 would illuminate when the target T was close (e.g. visually larger than the reference height, such as 1006) and the reference target 1004, the reference indicator 1006, reference multiples 1007a-c, the separator 1008, and one of the plurality of selectable aiming point indicators 1010 would illuminate when the target was far. In other words, one of the aiming point indicators 1010 is used to display the relative aiming point 1000 when the aiming point is close to the target (e.g. within a distance equivalent to the chest height of a deer) and the path indicators 930 is used to display the absolute aiming point 982 when the aiming point is far from the target T but still visible in the display 30, or when the distance to the target T is short.
FIG. 13C shows a currently preferred embodiment of a layout for the display segments. An exemplary display 30 comprises segments forming cross hairs 900, a horizontal distance indicator 914, a second numerical indicator 990, multiple reference images 1002, and a plurality of selectable aiming point indicators 1010.
The plurality of selectable aiming point indicators 1010 are dynamically and selectively illuminated to provide the relative aiming point 1000. When one of the aiming point indicators 1010 is not appropriate, either a too high indicator 1012 or a too low indicator 1014 is selectively illuminated.
The layout includes multiple reference images 1002 (shown as antelope reference image 1052 and deer reference image 1054) and relative target icons 1120 (a-b), each as a single segment, which are dynamically and selectively illuminated to provide the reference based on the settings.
The cross hairs 900 are positioned centrally in the display 30. The horizontal distance indicator 914 and second numerical indicator 990 are positioned peripherally, shown near the left edge of the display 30. The relative target icons 1120 (a-b) are positioned peripherally in the display 30, shown near the right edge of the display 30. The aiming point indicators 1010 are also positioned peripherally and centered on the relative target icons 1120 (a-b). The antelope reference image 1052 and deer reference image 1054 are positioned in relation to the lower relative target icon 1120b.
The layout also includes selectively illuminated setup indicator 1050, sight in indicator 1042, distance text 1044, drop text 1046, and a plurality of target type indicators 1048. The plurality of target type indicators 1048 are shown to include 20″ Target (see FIG. 13E represented FIG. 14A), 50 cm Target (see FIG. 13E represented FIG. 14B), antelope (e.g. see FIG. 12C), deer (e.g. see FIG. 12A and FIG. 12A), and elk (see FIG. 12B). Other target type indicators could be included, for example, such as turkey (see FIG. 12D), prairie dog (see FIG. 12E), enemy (see FIG. 12F), tank (see FIG. 12G), or concentric circle targets (see FIG. 12H).
FIG. 13D shows another preferred hybrid embodiment of a display layout for use with bows, pistols, rifles, muzzleloaders, etc. where all the elements of FIG. 13C are combined with the path indicators 930 and off screen indicator 932 as shown in FIG. 13B. In this embodiment, one of the aiming point indicators 1010 is used to display the separate and distinct relative aiming point 1000 when the aiming point is close to the target T (e.g. within a distance equivalent to the chest height of a deer) and the path indicators 930 is used to display the separate and distinct absolute aiming point 982 when the aiming point is far from the target T but still visible in the display 30, or when the distance to the target T is short.
Relative Target Icon
FIG. 13E shows display 30 with the reference image 1002 as a relative target icon 1120, which is indicated as 20″ target by the target type indicator 1048. In this example, the relative aiming point 1000 is shown a few inches above the relative target icon 1120 which corresponds to the aiming point at 346 yards (as shown in the a horizontal distance indicator 914) for the specific firearm, and the target in the cross hairs 900.
Aiming Point Relative to Enlarged Target Display
FIG. 13 illustrates a digital display 31 showing a relative aiming point 1000 relative to an enlarged target image 1020.
FIG. 13 illustrates a digital display 31 showing an embodiment of a relative aiming point 1000 shown relative to a reference of a predetermine size. The digital display 31 shows cross hairs 900 (shown here with a center circle) which are placed on the target T. The digital display 31 dynamically shows that the horizontal range is four hundred yards in a horizontal distance indicator 914.
In this embodiment, the reference is shown as an enlarged target image 1020. The enlarged target image 1020 is separate and distinct display element from the target T. When the target T is ranged, a digital snapshot is taken of the target T. The line of sight distance to the target T is known and thus can be enlarged to provide a reference of a predetermined size. The digital device 10 can optionally measure the chest height from the belly to the top of the back, and display the chest height in reference measurement 1022.
This embodiment also shows reference target 1004 placed in the reference image 1002.
The user 100 can range the target by tapping anywhere on a touch screen. Alternatively the user can click a physical button on the device or an optional virtual button on the screen such as the range button identified as input 34a.
The operation is similar to the operation of the display as described in reference to FIG. 12A, with the reference image 1002 being the enlarged target image 1020, and the optional calculation of the actual reference height.
The digital display 31 also provides an input to enter set up mode, i.e. a virtual settings control 1032 buttons. When the input is selected the device enters setup mode (see FIG. 15).
Aiming Point Relative to Zoomed Target Display
FIGS. 14A and 14B illustrate embodiments of digital displays 31 showing relative aiming points 1000 relative to an zoomed target image, and zoom controls 1030.
FIG. 14A illustrates a digital display 31 showing a relative aiming point 1000 relative to an zoomed target T image.
FIG. 14A illustrates a digital display 31 showing an embodiment of a relative aiming point 1000 shown relative to a reference of a predetermine size. The digital display 31 shows cross hairs 900 (shown here with a center circle) which are placed on the target T. The digital display 31 dynamically shows that the horizontal range is three hundred yards in a horizontal distance indicator 914.
In this embodiment, the reference is shown as a zoomed image of the target T. There is not separate reference.
The digital display includes a zoom control 1030 which allows the user 100 to zoom in and zoom out, and which displays the current zoom factor, e.g. 20×.
The user 100 can range the target by tapping anywhere on a touch screen (except in the zoom control). Alternatively the user can click a physical button on the device or a virtual button on the screen (not shown).
The operation is similar to the operation of the display as described in reference to FIG. 12A, with the reference image 1002 being the zoomed image of target T.
The digital display 31 also provides an input to enter set up mode, i.e. a settings control buttons. When the input is selected the device enters setup mode.
FIG. 14B shows the same embodiment as FIG. 14A where the target T is ranged at 200 yards. Notice that the deer appears larger at the same zoom factor because it is closer. The relative aiming point 1000 is relative lower than in the 300 yard example of FIG. 14A. In this example, the relative aiming point 1000 is below the deer's back.
Settings and Calibration Related to Relative Aiming Point Embodiments
Various settings have been discussed above.
FIG. 15 illustrates a digital embodiment of a display showing various settings 1034.
Settings for units (i.e. yards or meters) and mode (bow or rifle) are well known as discussed above.
In the currently preferred embodiment, the user does not enter a ballistic code or a bullet drop directly, but uses the novel real calibration processes using a relative target as described below in reference to FIGS. 16A through FIG. 20F.
Relative Target
U.S. patent application Ser. No. 14/471,786 first showed the use of a specially printed target to calibrate a rangefinder to a user's specific bow sight on a specific bow that was set to a specific type of arrow.
FIG. 14A shows a novel relative target 1100 which can be used with a method aspect of this invention to calibrate a rangefinder device to any user's specific bow, crossbow, pistol, rifle or other firearm with a specific type of arrow or ammunition. The markings on the relative target 1100 comprise of four concentric squares 1110 (a-d) having sides measuring 20 inches, 15 inches, 10inches, and 5 inches, respectively, an “X” marking the target center 1102, and a measuring scale 1112 indicating the number of inches below the target center 1102.
FIG. 14B shows a metric version of the relative target 1100 of FIG. 14A. The four concentric squares 1110 (a-d) having sides measuring 50 cm, 37.5 cm, 25 cm, and 12.5 cm, respectively. In the metric embodiment measuring scale 1112 indicates the number of centimeters below target center 1102.
In the preferred embodiment, the metric version, as shown in FIG. 14B, which is slightly smaller that the Imperial inches version, as shown in FIG. 14A, is printed on the back of the inches version.
FIG. 14C shows an alternate version of the four concentric squares 1110 (a-d) the relative target 1100 of FIG. 14A. The four concentric squares 1110 (a-d) having sides measuring 20 inches, 15inches, 10 inches, and 5 inches, respectively. This embodiment is preferred for very long range shooting, e.g. 1000 yards. Each band on the target is 2.5 inches wide and alternate dark (e.g. red) and white around the dark 5-inch center square 1110d. The outer band 1110a is white so that the four corners of the target 1100 will be seen around the scope's reticle cross hairs at distances over 500 yards.
Testing of an embodiment of this target worked well with a 6× riflescope where the four corners of the inner white band 1110c were visualized between the scope's heavy duplex cross hairs at 500 yards. At 500 yards, the crosshair intersection visually covers the 5-inch center square 1100d. With a 12× riflescope at 1000 yards, the target would be visualized the same way.
The relative target 1100 with this style of four concentric squares 1110 (a-d) would have a scale 1112 as shown in FIG. 14A.
Calibration instructions 198 could also be printed on the lower half of the relative target 1100. The following sections will discusses examples of how the relative target 1100 is used to calibrate the range finding device 10.
Relative Target Preparation with a Specific Bow and Arrow
FIGS. 15A through 15D illustrate the steps of the relative target preparation process with a bow. FIG. 15A shows a user 100 shooting an arrow 104 with a bow 102 at the relative target 1100 placed on a horizontal line of sight 3 at 20 yards. When the bow sight 110 20-yard pin 220 is set properly, the arrow 104 will hit the target center 1102 (not visible at this scale). The user 100 can shoot an arrow in the configuration shown in FIG. 15A to confirm that the 20-yard pin 220 is properly set for that specific bow 102 and that specific arrow 104. The projectile trajectory 2 is shown as a dashed line.
The next step, as shown in FIG. 15B is to move the relative target 1100 to 30 yards on the horizontal line of sight 3, and shoot the arrow 104 while aiming with the 20-yard pin 220 at the target center 1102. The arrow will follow the same projectile trajectory 2, but with the longer distance will hit the relative target 1100 at a lower point, in this example, with about a 4 inch drop, where the arrow will make a first shot mark 1130a (see FIG. 15D).
The next step, as shown in FIG. 15C is to move the relative target 1100 to 40 yards on horizontal line of sight 3, and shoot the arrow 104 while aiming with the 20-yard pin 220 at the target center 1102. The arrow will follow the same projectile trajectory 2, but with the even longer distance will hit the target at a lower point, in this example, with about a 12 inch drop, where the arrow will make a second shot mark 1130b (see FIG. 15D).
FIG. 15D illustrates the relative target 1100 showing the first shot mark 1130a, corresponding to the 30-yard shot, and the second shot mark 1130b, corresponding to the 40-yard shot.
Ballistic Calibration to a Specific Bow and Arrow
FIGS. 16A through 16F show the bow ballistic calibration process used to calibrate the device 10 to a specific bow and arrow. In these figures the display 30 corresponds to the currently preferred display element configuration as shown in FIG. 13D.
Initially, the rangefinder device 10 is put into setup mode and the yard or metric setting has been selected, in this example yard (or Imperial) mode, bow mode has been selected, and the 20″ target reference icon has been selected. As shown in FIG. 16A, setup mode is indicated by selectively illuminating the setup indicator 1050. Bow mode is indicated by selectively illuminating the bow mode indicator 992. The yard mode is indicated be selectively illuminating the “Y” as the units in the horizontal distance indicator 914. The upper relative target icon 1120a is illuminated, and because the device 10 is in yard mode, the ‘20″ Target’ target type indicator 1048 is illuminated.
Next, as shown in FIG. 16A, the bow sight in distance of 20 yards is displayed in the display 30. In the preferred embodiment, the “Sight In” indicator 1042, “Distance” text 1044, and the “20 Y” horizontal distance indicator 914 would be flashing indicating that the bow sight in distance is currently being set. The user can accept 20-yards or cycle through a preset sequence, such as 20, 30, 40.
Next as shown in FIG. 16B the words “Sight In” 1042 disappear and the word “Distance” 1044 continues to flash. If 20 were selected as the Sight In distance, the user can sequence through 30, 40, 50, 60 to select the first distance mark. In this case the user selects 30.
Next, after the 30-yard distance is selected and confirmed as shown in FIG. 16C, “Distance” 1044 stops flashing, and one of the aiming point indicators 1010 and the word “Drop” start to flash.
At this point, the user aims the device 10 to view the prepared relative target 1100, as shown in FIG. 15D. As shown in FIG. 16D, the user matches the visualized image of the relative target 1100 to the relative target icon 1120 shown in the display. This is done by hanging the relative target 1100 at eye level and positioning the device 10 at a distance such that the size of the relative target icon 1120 matches the visualized size of the relative target 1100 through the optics of the device 10. Each time the user hits a button, the flashing aiming point indicator 1010 moves down one location. The user moves the flashing aiming point indicator 1010 down until it visually matches the first shot mark 1130a. For each location, the corresponding drop amount is displayed (e.g. 4.5 inches).
Next, after the 30-yard shot mark 1130a is matched and confirmed, as shown in FIG. 16E the words the word “Distance” 1044 flashes again. If 20 was selected as the Sight In distance, and 30 was selected as the first distance mark, the user can continue to sequence through 40, 50, 60 to select the second distance mark. In this case, the user selects 40.
Next, after the 40-yard distance is selected and confirmed as shown in FIG. 16F, “Distance” 1044 stops flashing, and one of the aiming point indicators 1010 and the word “Drop” start to flash.
The user moves the flashing aiming point indicator 1010 down until it visually matches the second shot mark 1130b. At this point, the drop amount will show 12 inches.
At this point, three sets of values have been entered during the configuration process: 1) the sight in or zero at distance (e.g. 20 Y), 2) the first shot mark 1130a distance and visual drop (e.g. 30 Y and 4.5 inches), and 3) the second shot mark 1130b distance and visual drop (e.g. 40 Y and 12 inches). These three points are then used with the starting coordinate of (0,0) to determine a real projectile trajectory 2 which would be generally parabolic and adjusted for the real characteristics of the specific bow 102, specific arrow 104, the archer 100, and the environmental conditions such as altitude, humidity, air density, and their impact on the arrow's trajectory. This real calibration is superior to selection of a ballistic curve from a finite set of predetermined curves.
Relative Target Preparation with a Specific Rifle and Ammunition
FIGS. 17A through 17D illustrate the steps of the relative target preparation process with a specific rifle and specific ammunition. FIG. 17A shows a user 100 shooting a rifle 300 at the relative target 1100 placed on a horizontal line of sight 3 at 200 yards. When the riflescope is zeroed at, or sighted in at, 200 yards, the bullet will hit the target center 1102 (not visible at this scale). The user 100 can shoot a bullet in the configuration shown in FIG. 17A to confirm that the rifle scope is properly sighted in or zeroed for that specific rifle 300 and that specific ammunition. The projectile trajectory 2 is shown as a dashed line.
The next step, as shown in FIG. 17B is to move the relative target 1100 to 300 yards on the horizontal line of sight 3, and shoot the rifle 300 while aiming with the riflescope at the target center 1102. The bullet will follow the same projectile trajectory 2, but with the longer distance will hit the relative target 1100 at a lower point, in this example, with about an 8 inch drop, where the bullet will make a first shot mark 1130a (see FIG. 17D).
The next step, as shown in FIG. 17C is to move the relative target 1100 to 400 yards on horizontal line of sight 3, and shoot the rifle 300 while aiming with the riflescope at the target center 1102. The bullet will follow the same projectile trajectory 2, but with the even longer distance will hit the target at a lower point, in this example, with about a 19 inch drop, where the bullet will make a second shot mark 1130b (see FIG. 17D).
FIG. 17D illustrates the relative target 1100 showing the first shot mark 1130a, corresponding to the 300-yard shot, and the second shot mark 1130b, corresponding to the 400-yard shot.
Ballistic Calibration to a Specific Rifle and Ammunition
FIGS. 18A through 18F show the rifle ballistic calibration process used to calibrate the device 10 to a specific rifle and specific ammunition. In these figures the display 30 corresponds to the currently preferred display element configurations as shown in FIG. 13C or FIG. 13D.
Initially, the rangefinder device 10 is put into setup mode and the yard or metric setting has been selected, in this example yard (or Imperial) mode, rifle mode has been selected, and the 20″ target reference icon has been selected. As shown in FIG. 18A, setup mode is indicated by selectively illuminating the setup indicator 1050. The yard mode is indicated be selectively illuminating the “Y” as the units in the horizontal distance indicator 914. The upper relative target icon 1120a is illuminated, and because the device 10 is in yard mode, the ‘20″ Target’ target type indicator 1048 is illuminated.
Next, as shown in FIG. 18A, the sight in distance of 100 yards is displayed in the display 30. In the preferred embodiment, the “Sight In” indicator 1042, “Distance” text 1044, and the “50 Y” horizontal distance indicator 914 would be flashing indicating that the sight in distance is currently being set. The user can accept 50-yards or cycle through a preset sequence, such as 100, 150, 200, 250. The user selects 200 yards sight in distance.
Next as shown in FIG. 18B the words “Sight In” 1042 disappear and the word “Distance” 1044 continues to flash. If 200 were selected as the Sight In distance, the user can sequence through 100, 150, 250, 300, 350, 400 to select the first distance mark. In this case the user selects 300.
Next, after the 300-yard distance is selected and confirmed as shown in FIG. 18C, “Distance” 1044 stops flashing, and one of the aiming point indicators 1010 and the word “Drop” start to flash. In this example, because the current distance is 300 yards, which is greater than the sight in distance of 200 yards, the one of the plurality of aiming point indicators 1010 that corresponds to the target center 102 will be flashing.
At this point, the user aims the device 10 to view the prepared relative target 1100, as shown in FIG. 17D. As shown in FIG. 18D, the user matches the visualized image of the relative target 1100 to the relative target icon 1120 shown in the display. This is done by hanging the relative target 1100 at eye level and positioning the device 10 at a distance such that the size of the relative target icon 1120 matches the visualized size of the relative target 1100 through the optics of the device 10. Each time the user hits a button, the flashing aiming point indicator 1010 moves down one location. The user moves the flashing aiming point indicator 1010 down until it visually matches the first shot mark 1130a. For each location, the corresponding drop amount is displayed (e.g. 7.5 inches). Note that in this embodiment the distance between the plurality of aiming point indicators 1010 corresponds to 2.5 inches, so 7.5 is the closest increment to 8 inches.
Note that in other embodiments, the plurality of aiming point indicators 1010 could be configured to correspond to 1-inch increments or 0.5 inch increments. In yet another embodiment, once the mark is visually marked to the closest increment, a fine tuning mode could be entered where each time the button is pressed the drop amount is changed by 0.5 inches.
Next, after the 300-yard shot mark 1130a is matched and confirmed, as shown in FIG. 18E the words the word “Distance” 1044 flashes again. If 200 was selected as the Sight In distance, and 300 was selected as the first distance mark, the user can continue to sequence through 350, 400 to select the second distance mark. In this case, the user selects 400.
Next, after the 400-yard distance is selected and confirmed as shown in FIG. 18F, “Distance” 1044 stops flashing, and one of the aiming point indicators 1010 and the word “Drop” start to flash.
The user moves the flashing aiming point indicator 1010 down until it visually matches the second shot mark 1130b. At this point, the drop amount will show 20 inches (which is the closest 2.5 increment to 19 inches).
At this point, three sets of values have been entered during the configuration process: 1) the sight in or zero at distance (e.g. 200 Y), 2) the first shot mark 1130a distance and visual drop (e.g. 300 Y and 7.5 inches), and 3) the second shot mark 1130b distance and visual drop (e.g. 400 Y and 20 inches). These three points are then used with the starting coordinate of (0,0) to determine a real projectile trajectory 2 which would be generally parabolic and adjusted for the real characteristics of the specific rifle 300, specific ammunition, the user 100, and the environmental conditions such as altitude, humidity, air density, and their impact on the bullet's trajectory. This real calibration is superior to selection of a ballistic curve from a finite set of predetermined curves.
Alternative Relative Target Preparation
FIGS. 19A through 19D illustrate the steps of the relative target preparation process with a specific rifle and specific ammunition, where the user does not have a long shooting range or wants to calibrate using a shorter shot distance. FIG. 19A shows a user 100 shooting a rifle 300 at the relative target 1100 placed on a horizontal line of sight 3 at 200 yards. When the riflescope is zeroed at, or sighted in at, 200 yards, the bullet will hit the target center 1102 (not visible at this scale). The user 100 can shoot a bullet in the configuration shown in FIG. 19A to confirm that the rifle scope is properly sighted in or zeroed for that specific rifle 300 and that specific ammunition. The projectile trajectory 2 is shown as a dashed line. Up until this point, the process is the same as shown in FIG. 17A; however, the next step will be different.
The next step, as shown in FIG. 19B, is to move the relative target 1100 to 100 yards on the horizontal line of sight 3, and shoot the rifle 300 while aiming with the riflescope at the target center 1102. Unlike FIG. 17B, this is a distance shorter than the sight in distance of 200 yards. The bullet will follow the same projectile trajectory 2, but with the shorter distance will hit the relative target 1100 at a higher point, in this example, with about a negative −2.5 inch drop, where the bullet will make a first shot mark 1130a (see FIG. 19D).
The next step, as shown in FIG. 19C, is to move the relative target 1100 to 300 yards on horizontal line of sight 3, and shoot the rifle 300 while aiming with the riflescope at the target center 1102. The bullet will follow the same projectile trajectory 2, but with the longer distance will hit the target at a lower point, in this example, with about an 8 inch drop, where the bullet will make a second shot mark 1130b (see FIG. 19D).
FIG. 19D illustrates the relative target 1100 showing the first shot mark 1130a, corresponding to the 100-yard shot, and the second shot mark 1130b, corresponding to the 300-yard shot.
Alternate Ballistic Calibration
FIGS. 20A through 20F show the rifle ballistic calibration process used to calibrate the device 10 to a specific rifle and specific ammunition where the relative target has been prepared with at first shot mark 1130a which was shot at a distance less than the sight in distance. In these figures, the display 30 corresponds to the currently preferred display element configurations as shown in FIG. 13C or FIG. 13D.
Initially, the rangefinder device 10 is put into setup mode and the yard or metric setting has been selected, in this example yard (or Imperial) mode, rifle mode has been selected, and the 20″ target reference icon has been selected. As shown in FIG. 20A, setup mode is indicated by selectively illuminating the setup indicator 1050. The yard mode is indicated be selectively illuminating the “Y” as the units in the horizontal distance indicator 914. The upper relative target icon 1120a is illuminated, and because the device 10 is in yard mode, the ‘20″ Target’ target type indicator 1048 is illuminated.
Next, as shown in FIG. 20A, the sight in distance of 100 yards is displayed in the display 30. In the preferred embodiment, the “Sight In” indicator 1042, “Distance” text 1044, and the “50 Y” horizontal distance indicator 914 would be flashing indicating that the sight in distance is currently being set. The user can accept 50-yards or cycle through a preset sequence, such as 100, 150, 200, 250. The user selects 200 yards sight in distance. Up to this point, the setup process is the same as with FIG. 18A.
Next as shown in FIG. 20B the words “Sight In” 1042 disappear and the word “Distance” 1044 continues to flash. If 200 were selected as the Sight In distance, the user can sequence through 100, 150, 250, 300, 350, 400 to select the first distance mark. In this case the user selects 100.
Next, after the 100-yard distance is selected and confirmed as shown in FIG. 20C, “Distance” 1044 stops flashing, and one of the aiming point indicators 1010 and the word “Drop” start to flash. In this example, because the current distance is 100 yards, which is less than the sight in distance of 200 yards, the highest one of the plurality of aiming point indicators 1010 will be flashing. As shown here the highest of aiming point indicators 1010 corresponds to a negative −10.0 in. drop.
At this point, the user aims the device 10 to view the prepared relative target 1100, as shown in FIG. 19D. As shown in FIG. 20D, the user matches the visualized image of the relative target 1100 to the relative target icon 1120 shown in the display. This is done by hanging the relative target 1100 at eye level and positioning the device 10 at a distance such that the size of the relative target icon 1120 matches the visualized size of the relative target 1100 through the optics of the device 10. Each time the user hits a button, the flashing aiming point indicator 1010 moves down one location. The user moves the flashing aiming point indicator 1010 down until it visually matches the first shot mark 1130a. For each location, the corresponding drop amount is displayed (e.g. −2.5 inches).
Next, after the 100-yard shot mark 1130a is matched and confirmed, as shown in FIG. 20E the words the word “Distance” 1044 flashes again. If 200 was selected as the Sight In distance, and 100 was selected as the first distance mark, the user can continue to sequence through 150, 300, 350, 400 to select the second distance mark. In this case, the user selects 300.
Next, after the 300-yard distance is selected and confirmed as shown in FIG. 20F, “Distance” 1044 stops flashing, and one of the aiming point indicators 1010 and the word “Drop” start to flash.
The user moves the flashing aiming point indicator 1010 down until it visually matches the second shot mark 1130b. At this point, the drop amount will show 7.5 inches (which is the closest 2.5 increment to 8 inches).
At this point, three sets of values have been entered during the configuration process: 1) the sight in or zero at distance (e.g. 200 Y), 2) the first shot mark 1130a distance and visual drop (e.g. 100 Y and −2.5 inches), and 3) the second shot mark 1130b distance and visual drop (e.g. 300 Y and 7.5 inches). These three points are then used with the starting coordinate of (0,0) to determine a real projectile trajectory 2 which would be generally parabolic and adjusted for the real characteristics of the specific rifle 300, specific ammunition, the user 100, and the environmental conditions such as altitude, humidity, air density, and their impact on the bullet's trajectory. This real calibration is superior to selection of a ballistic curve from a finite set of predetermined curves.
Display Interface Guidelines
The use of display 30 during the setup process examples illustrated in FIGS. 16A-16F, FIGS. 18A-18F, and FIGS. 20A-20F, respectively illustrate some guidelines for implementing the setup process. Only the relevant display elements are illuminated at any point in time. Display elements related to the data currently being set flash. For example, when the sight in distance is being set, the words “Sight In” 1042 and “Distance” 1044 flash. When the first or second shot distance is being set, the word “Sight In” 1042 is not illuminated, and only the word “Distance” 1044 flashes. When the aiming point indicator 1010 is being matched to the first or second shot mark 1130 (a or b), the selected aiming point indicator 1010 and the word “Drop” 1046 flash. The user is given a number of options that are appropriate for the current context. For example, in bow mode the ranges for sight in distance may start at 20 yards, and in rifle mode the ranges for sight in distance will be longer and start at 50 or 100 yards. After the user has some preliminary values, then the subsequent values options should start at a reasonable point in the sequence. However, the user should be able to cycle through the entire sequence and start over again.
In hybrid embodiments that support multiple modes the user could calibrate for a specific bow and arrow in bow mode setup and then calibrate for one or more specific firearm and ammunition pairs in rifle or other firearm modes. Once calibrated for multiple real ballistic curves, the user would easily be able to select one of the real ballistic curves and corresponding mode.
Operation After Calibration
As discussed in the previous sections, our novel relative target and relative target icon can be used a universal calibration method for any range finding device 10. After the range finding device 10 has been calibrated to one or more real ballistic curves, then the operation of the preferred embodiment is as described in relation to FIG. 12C and FIG. 14A.
During calibration the upper relative target icon 1120a of the layout of FIG. 13C (or FIG. 13D) is used. However during the normal operation the lower relative target icon 1120b of the layout of FIG. 13C (or FIG. 13D) is used. Having the two relative target icons 1120 (a-b) allows for the plurality of aiming point indicator 1010s to be used for the dual purposes of calibration and for normal operation, thus reducing the total number of display elements required to implement the display 30.
Other Alternatives
In the foregoing examples, the user is able to specify the sight in distance. The setup steps could be simplified by have a default sight in distances, for example, the bow sight could default to 20 yards, and the rifle sight in distance could default to 100 yards for lower end range finding devices and 200 yards for higher end range finding devices. The design choice would simplify setup but reduce user control and flexibility.
In the foregoing examples, two shot distances and two shot marks were used to calibrate the range finding device. The ballistic curve may be slightly improved with a third or forth set of distances and drop coordinates; however, these would increase the complexity of the calibration method. For lower end rangefinder a single shot distance could be used. In some embodiments the user could choose to enter zero or more distances and drop coordinates. If zero were entered, a default standard curve would be used. If one or more coordinates were entered the additional data would be used to approximate the best estimated of the ballistic curve based on the amount of data entered.
Full Projectile Trajectory Sequence Display with Drift Adjustments
FIG. 21 illustrates a high-resolution display 31 showing a plurality of locations on a projectile trajectory adjusted for wind or weapon inertia.
Another advantage of the high-resolution display 31 is that the path indicators 930, shown in FIG. 29 as a sequence of dots, can be displayed anywhere on the display. For example, a cross wind will cause the projectile to drift. The user can enter data into the rangefinder device 10 to indicate the current relative cross wind speed (or estimate). The crosswind data can be correlated with projectile cross drag data to display a true aiming point (980 not shown) and show the corresponding diagonal sequence of points of the projectile trajectory. Preferably, an animation, as discussed in relation to FIG. 28, would show one point at a time with the corresponding intermediate range indication.
If a projectile is fired from a moving vehicle, such as a truck, jet, or a helicopter the projectile will have initial inertia (or acceleration) relative to the ground target. The computing element 16 (FIG. 3) can adjust the display to show the apparent drift resulting from the inertia (velocity and/or acceleration) of the projectile at the time of firing. In these situations, the path on the display may be a curve and may rise from below the cross hairs (900).
Further, if the projectile misses the target, additional path indicators in an extended sequence could show where the projectile would be beyond the target. For example, the dots shown to the right of the cross hairs 900 could represent each yard after the target is missed. This provide projectile awareness in the case the target moves or is missed by the projectile.
Ballistic Groups
Different ammunition and different arrows have different ballistic behaviors. Bullet manufactures perform tests to create ballistic tables and to determine ballistic coefficients. For example a 444 Marliine with 265 grains, a 0.270 Winchester with 130 grains, and a 22 Hornet with 35grains each perform differently. For example, the 22 Hornet has a ballistic coefficient of 0.137 at 2,700 feet per second. The Hornet shoots pretty flat out to 200 yards where it has a 6.8 inch drop.
When each different ammunition is fired in a specific firing device, its true behavior is captured with the present invention. That true calibration is then used to select a ballistic table which is used by the system to display trajectory path information including an aiming point and an indication of a clear path.
Advantages
Faster
The clear shot technology and relative aiming point technology provides the user with visual indications that do not require mathematical calculations or adjustments. The user immediate sees and image in the rangefinder device, which is then replicated with the scope or sight on the firing device. In other words, the user stays “right brained” allowing for rapid and accurate action.
Accurate
The clear shot technology provides an accurate projective trajectory to a ranged target that takes into account the obstacles that may be in the trajectory.
The relative aiming point technology provides an accurate aiming point relative to the target size reference.
Effective
Because the clear shot technology provides an accurate projective trajectory to a ranged target that takes into account the obstacles that may be in the trajectory, the user can adjust the position of the shot to ensure that an unexpected obstacle will not interfere with the shot. Thus, the first shot will always reach its target being more effective.
The relative aiming point technology provides an accurate aiming point that can the user can intuitively match.
Confidence
The clear shot technology gives the user confidence that despite numerous obstacles that may be near a projectile trajectory that a difficult shot can be successfully taken.
The relative aiming point technology gives the user confidence that the target will be hit.
This increased confidence will improve the user's performance and satisfaction.
Adjustable
The embodiments of these displays and rangefinders can be adjusted to be consistent with an individual user and associated sights, for example the specific pins on a individual user's bow sight, and specific ammunition and scopes.
Lightweight
The enhanced features of the clear shot technology do not add weight to the convention device. Embodiments with a digital camera and a high-resolution display have lighter weight than conventional rangefinders.
Easy to Transport and Use
Devices containing the clear shot and relative aiming point technology are easy to transport and use. Embodiments with a digital camera and a high-resolution display are smaller.
Rapid Use
Embodiments that provide an aiming point are used rapidly without having to use brain power to select numbers and estimate an aiming point.
Conclusion, Ramification, and Scope
Accordingly, the reader will see that the enhanced displays, rangefinders, and methods provide important information regarding the projectile trajectory and importantly provide greater accuracy, effectiveness, and safety.
While the above descriptions contain several specifics these should not be construed as limitations on the scope of the invention, but rather as examples of some of the preferred embodiments thereof. Many other variations are possible. For example, the display can be manufactured in different ways and/or in different shapes to increase precision, reduce material, or simplify manufacturing. Further, this technology could be applied to military situations where the projectiles is fired from a cannon, tank, ship, or aircraft and where the obstacles could be moving objects such as helicopters or warfighters. On the battlefield with three dimensional information, e.g. from satellite imaging and computer maps and charts, a computer using clear shot technology could aim an fire multiple weapons over mountains and through obstacles to continuously hit multiple targets. The variations could be used without departing from the scope and spirit of the novel features of the present invention.
Although the invention has been described with reference to the preferred embodiments illustrated in the attached drawings, it is noted that equivalents may be employed and substitutions made herein without departing from the scope of the invention as recited in the claims.
Accordingly, the scope of the invention should be determined not by the illustrated embodiments, but by the appended claims and their legal equivalents.
Patent Application
20240384969
