Not Applicable
A portion of the material in this patent document may be subject to copyright protection under the copyright laws of the United States and of other countries. The owner of the copyright rights has no objection to the facsimile reproduction by anyone of the patent document or the patent disclosure, as it appears in the United States Patent and Trademark Office publicly available file or records, but otherwise reserves all copyright rights whatsoever. The copyright owner does not hereby waive any of its rights to have this patent document maintained in secrecy, including without limitation its rights pursuant to 37 C.F.R. § 1.14.
The technology of this disclosure pertains generally to an illumination apparatus, and more particularly to a flashlight with a rectangular beam pattern.
Generally, existing flashlights generate a circular, focused beam pattern that results in uneven dispersion in the form of a high intensity spot and much larger low-intensity spill pattern.
A significant need exists for the ability to illuminate one or more walls of a room with a uniform beam pattern that fills one or more wall surfaces. Existing systems fail to provide a uniform rectangular beam pattern for achieving such illumination.
An aspect of the present description is a rectangular wide-beam flashlight that utilizes a plurality of LEDs positioned in uniquely formed optical elements to generate a uniform, rectangular beam pattern configured to substantially illuminate one or more walls in a room.
In one embodiment, the flashlight uses a sequential array of LEDs that are radially disposed at or within optical elements or cavities configured to combine the output of the LEDs to form a substantially uniform and seamless, high-aspect ratio or wide rectangular beam for adequately illuminating one or more walls in a room.
In a further embodiment, the array of LEDs are disposed in a circular array that forms a combined angular swath greater than 180 degrees, and the beams from neighboring LEDs are configured to overlap so as not to provide black spots within the illumination beam. The optical elements may also be configured to taper the luminous intensity of respective beams at lateral fringes of beam where overlap may occur to blend or fuse the beams at the overlap locations.
In another embodiment, the wide-beam flashlight comprises a pair of retractable legs that may be extended from the flashlight housing to allow the flashlight to be propped up in a “hands-free” configuration.
The flashlight may also comprise logic components and a switch for selective control of each LED in the array of LEDs to provide varying beam widths or illumination patterns, and strobe option for dynamic illumination at a set frequency (e.g. flash mode).
Further aspects of the technology described herein will be brought out in the following portions of the specification, wherein the detailed description is for the purpose of fully disclosing embodiments of the technology without placing limitations thereon.
The technology described herein will be more fully understood by reference to the following drawings which are for illustrative purposes only:
The cover/lens 14 is configured to provide protection to the optical components and may comprise a clear arcuate cover that wraps around the front end of the optical head 12. The cover/lens 14 may be sealed between the upper surface and the lower surface of the optical head 12 with a rubber gasket (not shown). The cover/lens 14 is preferably disposed in a convex shape to reduce the likelihood that the lens will break if the flashlight is inadvertently dropped on the ground and strikes a rock. Cover/lens 14 may be shaped to provide certain optical qualities. For example, the lens 14 may have an hourglass-shaped cross-section (
The tail cap 22 is preferably attached to the battery compartment 20 via threads on both pieces and is sealed to prevent water leakage into the battery compartment with a rubber O-ring (not shown) that fits between the tail cap and the battery compartment. The tail cap 22 is preferably larger in diameter than the battery compartment 20, which helps to prevent the flashlight from slipping out of the user's hand, and also helps to form a contact surface to form a 3-point or tripod structure with the extended legs 18.
The battery compartment 20, optical head 12 and tail cap 22 of the flashlight 10 are preferably made out of aluminum, but may also be made out of plastic or steel. The optical head 12 may be made as a single part or made out of two shells that are fastened together with screws (not shown) connecting them. Rubber gaskets (not shown) may be used to seal all joints of the housing to prevent leakage of water.
While LEDs 50 may comprise any type of light source, in one embodiment they comprise high-power LEDs (e.g. 1000 lumen Cree LEDs). In one embodiment, the optical elements 40 are sized to be approximately 1.3 inches in length, with a width at the proximal end (at the LED 50) being approximately ⅓ the width at the distal end.
In the embodiment shown in
The strobe button 26 is located forward of the sliding switch 24 and may be programmed to activate all of the LEDs simultaneously with the right facing and left facing LEDs in strobe “flash bang” mode.
The USB connector 28 is located forward of the strobe button 26. The primary function of the USB connector 28 is to provide charging capability for the batteries. In addition, the USB connector 28 may provide digital signal connectivity between the circuit board 32 contained inside the housing and an external device (not shown) such as a cell phone or laptop computer. Digital connectivity may be used to monitor power consumption of the batteries, or to program a digital controller (e.g. within logic components 36) located on the circuit board 32 for custom functionality of the buttons and LEDs. The USB connector 28 may also be used to provide power from the flashlight batteries to an external device such as a cell phone.
In one embodiment, each LED 50, when illuminated, generates a resulting beam of light that has a nearly rectangular projected shape with an angular width Φ (in the X-Y plane) of approximately 45-50 degrees and a height (e.g. angular projection in the Z-Y plane or Z-X plane) of approximately 23 degrees. In this configuration, when all five LEDs 50 are simultaneously illuminated, the resulting combined illumination of the beams is a rectangular projected angular swathα of light that is approximately 225 degrees in width and 23 degrees in height. It is appreciated that the number of LEDs 50, and or shape, sizing or orientation of the optical elements 40 may be configured to cover any number of different configurations or ranges (e.g. projected angular swath α ranging from 120 degrees to 270 degrees or more, and more preferably between 180 degrees and 225 degrees).
The overlap angle β may be correspondingly small (e.g. 2 degrees to 5 degrees, or even one degree or less in some configurations), and configured to coincide at a specified distance from the flashlight corresponding to a particular expected range of distances (e.g. 10 feet-30 feet).
It is appreciated that the optical element shape/sizing and resulting beam patterns and illumination displayed in
A similar structure of the internal surface 54 may be generated vertically for upper and lower side walls (not shown) so as to generate a uniform distribution in the X-Z plane). Lens 40a of
It is appreciated that a portion of the curvature or surface 58 may be shaped, coated, etc. to provide an intensity taper region having angle Φ′, as shown in
Correspondingly, the outer-most optical element 40 in the array (see left-most and right-most optical elements 40 in
It is appreciated that reflector 40c shown in
It is further appreciated that the overlap defined by angle β in
While smooth forward edges are shown on the retaining plates in this embodiment, toothed or serrated forward edges can be included as previously described. The figures and related description are primarily directed to the beam shaping and light emission characteristics of this embodiment.
Each light shaping module is associated with a corresponding light source 106 such as a Cree LED as previously described. Each light shaping module includes a rear opening 108 through which the light source can extend or through which the light source otherwise can project light. In this regard, each light source is preferably soldered or otherwise attached to a circuit board 110 which in turn is attached to the rear of the light shaping module. The circuit board can be attached to the light shaping module using any conventional means suitable for the materials used. For example, attachment may be made using screws, pins or other fasteners 112 that extend through the circuit board and into corresponding holes 114 in the light shaping module. Due to the heat generated by Cree LEDs, the circuit board preferably has a metalized surface 116 on the LED side to act as a heat sink. The light sources are preferably soldered to traces 118 on the circuit board, and plated through holes and traces or other connectors (not shown) can be provided for electrical connections to the light source.
A backing plate 120 with a coupling 122 is attached to the rear of the optical head. The coupling 122 is configured for connection to a support structure such as a handle of the type previously described. The backing plate includes upper and lower flanges 124a, 124b for attachment to the upper and lower retaining plates, respectively, using any conventional means suitable for the materials used, such as, for example, holes and corresponding threads or other means with which screws, pins or other fasteners may used to securely connect the parts. It will be noted that the backing plate also functions as a barrier to block rearward protection of light so that the emitted light has an approximate one-hundred and eighty degree field of projection.
Note that five light shaping modules are shown in the array as a non-limiting embodiment. Additional light shaping modules could be used when desired, such as when increasing the size of the array for use as a light bar on a vehicle. If fewer light shaping modules are used, the beam pattern would degraded even in a smaller array such as would be used in a handheld flashlight of the type described herein. Furthermore, multiple such arrays could be stacked.
In the embodiment shown, the array of light shaping modules is configured to shape and project light uniformly from the light sources into a pattern with relatively constant angular divergence in both the horizontal and vertical directions. The illumination pattern in the vertical direction is narrower than the pattern in the horizontal direction and this illumination pattern appears substantially rectangular in shape when projected onto a surface that is equidistant (spherical) from the light source.
The configuration of a light shaping module in this embodiment is illustrated in more detail in
The homogenizer collects light from the light source and generates a relatively uniform output surface that is rectangular in nature in order to condition the beam to be projected. In this embodiment the homogenizer has is a light pipe with a square input surface (face) 130 and a square output surface (face) 132. The non-uniform light collected by the light pipe at one end is transported to the other end of the light pipe by mirrored reflections in such a way as to homogenize the light. The length of the light pipe should be selected to achieve enough light bounces to homogenize the light intensity at the output end of the light pipe.
It will be appreciated that light pipes can be flat mirrored surfaces with input and output faces that are circular or of any polygon shape but are typically rectangular, square, hexagonal in shape. The sizes of the input and output faces can be different for the same light pipe, which will change the angular projection output of the light pattern. The light pipe can be straight or tapered.
The beam shaping optic receives light from the homogenizer and radiates the light in a substantially uniform rectangular projected pattern. In this embodiment, the beam shaping optic comprises a Concentric Parabolic Concentrator (CPC) that conditions and shapes the beam to be projected. The inner surfaces 134 of the beam shaping optic are mirrored so that the light that is projected outward comprises a combination of direct light and light that is reflected off the mirrored surface. Light is projected with a substantially uniform output over a controlled solid angle in the vertical and horizontal directions. The beam shaping optic can comprise various materials such as, for example, a metal material with a highly polished surface or a plastic material with a reflective coating common in the industry.
As illustrated in
As described above, the basic shape of these types are optics are known as a Concentric Parabolic Concentrator (CPC). CPCs are described in detail in W. T. Welford and R, Winston, “High Collection Nonimaging Optics”, Academic Press (1989), for example, and thus will briefly be discussed here.
For a hollow reflective optic where the internal surface is air, the maximum length of the CPC is given by:
where a=the entrance aperture and θ=maximum projection angle in the x or y directions.
The length can be truncated, but it will reduce the sharpness edge of the light beam. Shortening the CPC length can be used to increase the transition zone between the light and dark illuminated areas where beams overlap over lap from adjacent light patches.
The x or y coordinate (r) of points on the as a function of the z coordinate along the axis is given by the positive real root of this quadratic equation:
C
2
r
2+2(CSz+aP2)r+(z2S2−2aCQz−a2PT)=0
where C=cos θ, S=sin θ, P=1+S, Q=1+P, and T=1+Q.
For an overall illumination pattern of 17 degrees by 180 degrees with reflectors with a 5 degree overlap, an angle of +/−21 degrees is needed in the y-direction. For a=1.85 mm and θ=21 degrees, L=18.26765, C=0.93358, S=0.35837, P=1.35837, Q=2.35837, and T=3.35837. Solving for the positive real root to the quadratic equation for the x-direction gives the values in Table 1. The surface is truncated (z is less than the maximum length (L)) in order to control the overlap regions between adjacent reflector assembles so that a relatively uniform continuous beam is achieved. In the x-direction, the 17 degree projection angle gives θ=8.5 degrees, L=96.12594, C=0.989016, S=0.147809, P=1.147809, Q=2.147809, and T=3.14780. Solving for the positive real root to the quadratic equation for the y-direction gives the values in Table 2. The surfaces can be truncated in order to achieve the best compromise of collection efficiency and size.
By way of example, and not of limitation
In
Surface 300 is optically reflective at about 60 angstroms rms and SAG Table 3 applies. The values in SAG Table 3 were determined according to:
where
a=0.978152378
b=0.292371705 (Z1)+4.874625844
c=0.021847622 (Z1)2−7.859605043 (Z1)−12.36578432
Surface 400 is optically reflective at about 60 angstroms rms and SAG Table 4 applies. The values in SAG Table 4 were determined according to:
where
a=0.871572413
b=0.669130606 (Z2)+6.8271049
c=0.128427587 (Z2)2−8.146386778 (Z2)−15.61310065
From the description herein, it will be appreciated that the present disclosure encompasses multiple embodiments which include, but are not limited to, the following:
1. A light projecting apparatus, comprising: (a) a housing configured to retain one or more power sources; and (b) an optical head extending from the housing, the optical head comprising: (i) a plurality of optical elements arranged in a sequential array: (ii) a plurality of light sources configured to be powered from the one or more power sources, each said light source disposed adjacent or within a corresponding one of said optical elements; (iii) each said optical element shaped to modify a beam of light emitted from a corresponding light source to generate a rectangular illumination pattern when projected on a planar surface; and (iv) wherein emitted light beams from adjacent optical elements overlap along at least one side of the emitted light beams such that adjacent light beams form a contiguous beam having a higher aspect ratio than each of the emitted light beams in isolation.
2. The apparatus of any preceding or following embodiment, wherein the optical elements are shaped to taper luminous intensity of each emitted light beam at a specified location corresponding to the adjacent beam overlap.
3. The apparatus of any preceding or following embodiment, wherein the light sources and optical elements are shaped to form a contiguous rectangular beam having an angular swath greater than 180 degrees.
4. The apparatus of any preceding or following embodiment, wherein each optical element comprises one or more surfaces that reflect, refract or diffuse light to taper the luminous intensity at a specified angle from peripheral lateral edges of the emitted beam of light to form an angular taper region at the lateral edges.
5. The apparatus of any preceding or following embodiment, wherein the one or more surfaces of the optical elements generate a central region between angular taper regions at the lateral edges, the central region comprising a substantially uniform distribution of luminous intensity.
6. The apparatus of any preceding or following embodiment, wherein at least one of the optical elements comprises a reflector having a concave segment and convex segment to distribute light substantially uniformly across the central region.
7. The apparatus of any preceding or following embodiment, wherein at least one of the optical elements comprises a lens shaped to direct light from a respective light source to form a total internal reflection (TIR) beam of collimated light at least across the central region.
8. The apparatus of any preceding or following embodiment, wherein the light sources comprise light emitting diodes (LEDs)
9. The apparatus of any preceding or following embodiment, wherein the light sources and optical elements are disposed in a radial array.
10. The apparatus of any preceding or following embodiment, further comprising a curved lens disposed opposite the LEDs from the optical elements to cover the light sources and optical elements.
11. The apparatus of any preceding or following embodiment, wherein the lens has a curvature configured to provide further dispersion of light.
12. The apparatus of any preceding or following embodiment: wherein the housing comprises an elongate first end for housing the one or more battery power sources and providing a handhold for a user, and said optical head at a second end for housing the light sources and optical elements; wherein the housing at the optical head comprises a surface for retaining a retractable bipod structure having a first folded position disposed flush with or retained in the housing and a second extended position that forms a pair of feet; and wherein upon placing the flashlight on a working surface with the bipod structure in the extended position, the pair of feet and first end of the housing form a tripod structure for securing the flashlight in a hands-free position and orienting the optical head upward at a specified angle with respect to the working surface.
13. The apparatus of any preceding or following embodiment, wherein the bipod structure comprises a hinge at one end and extends downward and outward in a lateral direction with respect to the optical head in the extended position.
14. The apparatus of any preceding or following embodiment, wherein the array comprises at least three light sources comprising a center light source and two peripheral light sources.
15. The apparatus of any preceding or following embodiment, wherein the light sources are coupled to a switch disposed within the housing, the switch having a first position where all light sources are off, a second position where only the center light source is on, and a third position where the center and periphery light sources are on.
16. The apparatus of any preceding or following embodiment: wherein the array comprises at least five light sources comprising two outer peripheral light sources opposite the center light source from the peripheral light sources; and wherein the switch has a fourth position that illuminates the entire array of five light sources.
17. The apparatus of any preceding or following embodiment, further comprising a second switch that activates all of the light sources to strobe or flash one or more of the light sources.
18. A light projecting apparatus, comprising: (a) a housing configured to retain one or more power sources; and (b) an optical head extending from the housing, the optical head comprising: (i) a plurality of optical elements arranged in a sequential array; (ii) a plurality of light sources configured to be powered from the one or more power sources, each said light source disposed adjacent or within a corresponding one of said optical elements; (iii) each said optical element shaped to modify a beam of light emitted from a corresponding light source to generate a rectangular illumination pattern when projected on a planar surface; and (iv) wherein emitted light beams from adjacent optical elements overlap along at least one side of the emitted light beams such that adjacent light beams form a contiguous beam having a higher aspect ratio than each of the emitted light beams in isolation; (c) wherein the housing comprises an elongate first end for housing the one or more battery power sources and providing a handhold for a user, and an optical head for housing the light source; (d) wherein the housing at the optical head comprises a surface for retaining a retractable bipod structure having a first folded position disposed flush with or retained in the housing and a second extended position that forms a pair of feet; and (e) wherein upon placing the flashlight on a working surface with the bipod structure in the extended position, the pair of feet and first end of the housing form a tripod structure for securing the flashlight in a hands-free position and orienting the optical head upward at a specified angle with respect to the working surface.
19. A light projecting apparatus, comprising: (a) a housing configured to retain one or more power sources; and (b) an optical head extending from the housing, the optical head comprising: (i) a plurality of optical elements arranged in a sequential array; (ii) a plurality of light sources configured to be powered from the one or more power sources, each said light source disposed adjacent or within a corresponding one of said optical elements; (iii) each said optical element shaped to modify a beam of light emitted from a corresponding light source to generate a rectangular illumination pattern when projected on a planar surface; (iv) wherein emitted light beams from adjacent optical elements overlap along at least one side of the emitted light beams such that adjacent light beams form a contiguous beam having a higher aspect ratio than each of the emitted light beams in isolation; (v) wherein the optical elements are shaped to taper luminous intensity of each emitted light beam at a specified location corresponding to the adjacent beam overlap; (vi) wherein optical elements comprise one or more surfaces that reflect, refract or diffuse light to taper the luminous intensity at a specified angle from peripheral lateral edges of the emitted beam of light to form an angular taper region at the lateral edges; and (vii) wherein the one or more surfaces of the optical elements generate a central region between angular taper regions at the lateral edges, the central region comprising a substantially uniform distribution of luminous intensity.
20. The apparatus of any preceding or following embodiment: wherein the light sources and optical elements are disposed in a radial array; and wherein the light sources and optical elements are shaped to form a contiguous rectangular beam having an angular swath greater than 180 degrees.
21. The apparatus of any preceding or following embodiment, wherein the light sources and optical elements are shaped to form a contiguous rectangular beam having an angular swath greater than 220 degrees.
22. A optical head apparatus for a flashlight, comprising: (a) a plurality of optical elements arranged in a sequential array; (b) a plurality of light sources configured to be powered from one or more power sources, each said light source disposed adjacent or within a corresponding one of said optical elements; (c) each said optical element shaped to modify a beam of light emitted from a corresponding light source to generate a substantially rectangular illumination pattern when projected on a planar surface; (d) wherein emitted light beams from adjacent optical elements overlap along at least one side of the emitted light beams such that adjacent light beams form a contiguous beam having a higher aspect ratio than each of the emitted light beams in isolation.
23. A optical head apparatus for a flashlight, comprising: (a) a plurality of optical elements arranged in a sequential array; (b) a plurality of light sources, each said light source associated with a corresponding one of said optical elements; (c) each said optical element shaped to modify a beam of light emitted from a corresponding light source to generate a substantially rectangular illumination pattern when projected on a planar surface; (d) wherein emitted light beams from adjacent optical elements overlap to collectively generate a contiguous beam that forms a substantially rectangular illumination pattern which projected on a planar surface, wherein said contiguous beam has a higher aspect ratio than each of the emitted light beams in isolation.
24. The apparatus of any preceding or following embodiment, wherein each said optical element comprises a homogenizer section and a beam shaping optic section.
25. The apparatus of any preceding or following embodiment, wherein the homogenizer collects and conditions light from the light source.
26. The apparatus of any preceding or following embodiment, wherein the beam shaping optic section comprises reflective surfaces that receive light from the homogenizer section and radiate the light in a substantially uniform rectangular projected pattern.
As used herein, the singular terms “a,” “an,” and “the” may include plural referents unless the context clearly dictates otherwise. Reference to an object in the singular is not intended to mean “one and only one” unless explicitly so stated, but rather “one or more.”
As used herein, the term “set” refers to a collection of one or more objects. Thus, for example, a set of objects can include a single object or multiple objects.
As used herein, the terms “substantially” and “about” are used to describe and account for small variations. When used in conjunction with an event or circumstance, the terms can refer to instances in which the event or circumstance occurs precisely as well as instances in which the event or circumstance occurs to a close approximation. When used in conjunction with a numerical value, the terms can refer to a range of variation of less than or equal to ±10% of that numerical value, such as less than or equal to ±5%, less than or equal to ±4%, less than or equal to ±3%, less than or equal to ±2%, less than or equal to ±1%, less than or equal to ±0.5%, less than or equal to ±0.1%, or less than or equal to ±0.05%. For example, “substantially” aligned can refer to a range of angular variation of less than or equal to ±100, such as less than or equal to ±50, less than or equal to ±4°, less than or equal to ±30, less than or equal to ±20, less than or equal to ±1°, less than or equal to ±0.5°, less than or equal to ±0.1°, or less than or equal to ±0.05°.
Additionally, amounts, ratios, and other numerical values may sometimes be presented herein in a range format. It is to be understood that such range format is used for convenience and brevity and should be understood flexibly to include numerical values explicitly specified as limits of a range, but also to include all individual numerical values or sub-ranges encompassed within that range as if each numerical value and sub-range is explicitly specified. For example, a ratio in the range of about 1 to about 200 should be understood to include the explicitly recited limits of about 1 and about 200, but also to include individual ratios such as about 2, about 3, and about 4, and sub-ranges such as about 10 to about 50, about 20 to about 100, and so forth.
Although the description herein contains many details, these should not be construed as limiting the scope of the disclosure but as merely providing illustrations of some of the presently preferred embodiments. Therefore, it will be appreciated that the scope of the disclosure fully encompasses other embodiments which may become obvious to those skilled in the art.
All structural and functional equivalents to the elements of the disclosed embodiments that are known to those of ordinary skill in the art are expressly incorporated herein by reference and are intended to be encompassed by the present claims. Furthermore, no element, component, or method step in the present disclosure is intended to be dedicated to the public regardless of whether the element, component, or method step is explicitly recited in the claims. No claim element herein is to be construed as a “means plus function” element unless the element is expressly recited using the phrase “means for”. No claim element herein is to be construed as a “step plus function” element unless the element is expressly recited using the phrase “step for”.
This application claims priority to, and the benefit of, U.S. provisional patent application Ser. No. 62/858,292 filed on Jun. 6, 2019, incorporated herein by reference in its entirety.
Number | Date | Country | |
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62858292 | Jun 2019 | US |
Number | Date | Country | |
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Parent | 17527484 | Nov 2021 | US |
Child | 17875800 | US | |
Parent | 17281204 | Mar 2021 | US |
Child | 17527484 | US |