Patent Application
20230218160
Subjective refraction is a procedure that remains one of the most challenging to train a technician to produce a consistent and accurate outcome. Auto refraction can be helpful to provide a starting point. However, subjective refraction remains the gold standard. No conventional, existing auto refractor can serve as a suitable replacement for a subjective refraction eye exam in terms of accuracy. To be proficient in subjective refraction requires extensive training, and the learning curve is very steep. It can take months, or even years before a refraction technician may master the technique of subjective refraction.
It is desired to provide a self service refraction instrument and method. Thereby, a patient can perform the measurement, either alone or with the supervision of a minimally trained technician at relatively low cost. Ideally, a procedure that can be entirely self-service without an expert operator present for at least a significant proportion of the testing time is greatly desired and would provide tremendous cost advantage. An entirely self-service subjective refraction instrument and procedure would provide even more cost saving by not needing the presence of any person other than the test subject herself or himself to run the refraction test. With such desired self service refraction instrument and method, a test subject or eye care patient could perform the measurement at a self service kiosk during which time the physician or optometrist would not need to be present, thus saving the test subject money. The desired self service eye testing solution would not require long term training or high cost, available during the duration of the self service refraction procedure. Such self service or minimal supervision refraction test would increase its usability, and provides substantial cost saving. The operation of the desired self service refraction device would also not be limited by the work hours of an operator of a conventional refraction eye examination instrument. The conventional operator-dependent refraction instrument may be idled due to sick days, vacation, leaves, and holidays.
A self service refraction process in accordance with an example embodiment may be described with reference to
A user of the service (from here on, the term of a patient, a test subject, a customer or a user of the service may be used interchangeably throughout the rest of the disclosure) who desires to have his or her vision improved by correcting refractive errors may approach a self service refraction instrument configured in accordance with an example embodiment.
A touch screen connecting to a computer for example, displays a message: “Touch to Start” as shown in 110 in
A training or introduction process may be displayed to the test subject with sound from speakers or may be provided as an option to new users which may be skipped by experienced users of the apparatus, and certain instructions may be provided, at 120 in
A training video may be displayed to the test subject at 120 in
A self-service refraction instrument in accordance with an example embodiment includes a computer processor or similar electronic device. The device is capable of receiving input from various human interface devices, such as a mouse, keyboard, touch screen, audio input, camera images, recognizing the presence of a patient in the vicinity, for example, and to perform measurements from the capture images, and so on.
As shown in 130 in the example embodiment illustrated at
In one example embodiment, the self-service refraction instrument may include a part that permits the test subject to perform a self-service auto refraction eye test. Examples of a working auto refractor mechanism include a Nidek refractor model Tono Ref II and a Topcon auto refractor model KR-8000. The auto refraction 130 component of the test may use a wave front aberrometer device. The details of example wavefront optics and instrument construction have been disclosed in published PCT patent application number WO03/034909A2), which is incorporated by reference.
Referring now to an example auto refraction process illustrated at
In an example embodiment, the test subject may perform self alignment of the test subject's eye or eyes with an auto refraction instrument, which may include:
a. An eye piece of the instrument;
b. A light source, projecting light into the eye, wherein light is reflected at the retina, and exits the pupil forming a lighted glow of the pupil;
c. A camera capturing the image of the user's pupil;
d. A monitor displaying the pupil image, wherein the user sees the pupil on the monitor;
e. A marker comprising a drawing of the boundary of a region, in which the intended eye location is within that region inside the marker's boundary, wherein the boundary can be in the shape of a square, a circle or an oval or ellipse or in the shape of a generic eye, wherein the center of the region defined by the boundary may be the intended location for the eye, and/or a pupil image may be overlapped with the pupil of the user when the pupil of the user is aligned.
The test subject or user of the self-service refraction instrument moves her eye to the center of a target boundary thereby aligning the eye to the intended position of the eye for an auto refraction image capture. Operation of the auto-refraction instrument and performance of an autorefraction eye test, and specifically alignment of the eyes of the user may include head tilt angle monitoring and feedback signals or other electronic or mechanical level guidance as may be described in further detail hereinbelow. Further examples include mechanical head stabilizing components such as a chin rest or forehead rest or other wearable head gear that may be mechanically coupled for stabilization relative to the auto refraction instrument or that may include an electronic level component that monitors head tilt angle and provides feedback to the user or an eye care technician regarding user head tilt angle before and/or during an auto refraction test.
Once the pupil positioning is done, the user may initiate a wave front image capture 220 as in the illustrative example embodiment of
In one embodiment, eye image capture is automatically triggered when the eye is inside the region defined by the marker. Certain eye image data may be gathered from analysis of the captured image of the test subject's eye including wavefront data of the eye, the pupil size, and the user's papillary distance. In certain embodiments, the optical path length and head tilt angle may be measured and utilized for instrument calibration and/or image data editing or processing.
In one embodiment, a method of converting a wavefront image to an auto refraction prescription may include the following steps:
a. Capturing a wavefront profile from a test subject using a self-service refraction apparatus at 220 in
b. Decomposing the wavefront profile into Zernike components at 230 in
c. Calculating a best fit that matches the decomposed wavefront profile to a set of values in sphere, cylinder and axis at 240 in
The desired outcome is to identify the best sphere, cylinder and axis values 250, that provide the best fit to the eye's Zernike profile. These new second order terms from the calculation are the wavefront auto refraction correction terms that the decision module 460 may decide to use as a starting prescription of a corrective optics 260 for a self-service subjective refraction process 270 by applying these values to the corresponding optical components for sphere 422, and astigmatism 444 in the optical assembly that is used in the self-service subjective refraction test 270. A process in accordance with certain embodiments may include generating a correction wavefront profile based on measured aberrations of the eyes of a user and/or test subject using a self service refraction device in accordance with an example embodiment.
As illustrated in
a. aligning test subject's eyes with an autorefraction instrument 210
b. measuring a wavefront image 220;
c. generating a wavefront profile 230;
d. calculating a Zernike profile 240;
e. calculating sphere, cylinder and axis values 250; and
f. generating a correction wavefront profile as a starting point 260 for a subjective refraction process 270.
A self service subjective refraction eye examination by decision module in accordance with various example embodiments may take into account various test subject responses to questions involving comparative choices of corrective optics and the clarity, intensity and/or geometry of viewing targets observed through those choices of corrective optics. In a self-service subjective refraction eye examination by decision module in accordance with an example embodiment, a patient (the customer, the test subject or the user of the self-service refraction instrument, apparatus, device, or kiosk) has to pick among presented corrective vision options, for example, by indicating which option appears to present a viewing target with better clarity or better focus.
The viewing target may include one or more points, lines, letters and/or universal symbols, or a still image or scene, or a video sequence, or a live view or combinations thereof. The apparatus may provide a voice prompt, telling the patient what type of response is expected from her or him. The patient can use her voice, or another human user interface device, such as a mouse, a joystick, or a camera detection of hand gestures, or body movements to indicate choices, answers or picks, which will be received as input to a program running on the self-service refraction apparatus in accordance with an example embodiment that includes a processor-controlled, self service refraction test device that includes a decision module 460.
In an example situation during a self service refraction eye test, the patient may be asked by digital voice generation or text on a display screen, “which one is more clear, choice 1, or choice 2?” The patient may reply by saying into a microphone: “2.”, or he or she may use a mouse to roll the wheel up for answering “1” or roll down to indicate the answer is“2”, or by pushing a joystick up for “1” and pushing the joystick down for “2” or by tapping a touch screen or touch pad, or foot tap or another gesture in a camera's view or within range of a microphone.
As illustrated in an example workflow in
A self service subjective refraction instrument (or component of a broader use instrument) may include an optical assembly in accordance with several different configurations of lenses and/or other optical components. Examples of such an optical assembly that may be included in certain example embodiments of a self service refraction device, and examples of certain steps in a self service refraction method that may use such a device, or a different device, have been disclosed in U.S. Pat. No. 7,699,471, and in U.S. Pat. Nos. 10,383,512, 10,194,794, 8,967,801, 8,366,274, and 7,726,811, each by the same inventor Shui Lai, and each being hereby incorporated by reference. The optical assembly has adjustable optical power in sphere, cylinder and axis in certain embodiments, or just sphere and cylinder in certain embodiments, and higher order aberrations may be diagnosed and corrected in certain embodiments along with sphere and cylinder or along with sphere, cylinder and axis. The available optical powers may be aligned or positioned at the equivalent cornea plane of the user's eye during an example self service refraction exam process using a device such as one of the example embodiments illustrated in block form in
The decision module 460 comprises digital code embedded in an electronic storage medium that produces output commands that instruct the processor 410 to configure a specific viewing target and a specific configuration of corrective optics for presentation to a test subject. In certain embodiments, the decision module 460 may instruct the processor 410 to communicate to the test subject, e.g., using an electronic display interface 430 or a voice interface, questions asking the test subject to compare, contrast or choose between two images of a viewing target. In example embodiments, the decision module 460 may instruct the processor 410 to communicate questions to the test subject such as, “does the viewing target appear more round” or “less elongated,” or “more red” or “more blue” or “more or less monochrome” or “does the viewing target appear more or less uniform in brightness” or “more less uniform in color” or “more or less gray,” either compared with a previous image or in an absolute sense. That is, the decision module 460 may instruct the processor 410 to communicate certain questions to the test subject regarding the viewing target's appearance, i.e., blurriness, clarity, size, shape, to the test subject either absolutely or comparatively or both. Answers to these questions are provided by the test subject by actuating an input device 440 which the processor 410 configures as digital input data to inform the decision module 460. The input device 440 may include a joystick, a keypad, a mouse, a keyboard, a touch screen, or a microphone. The decision module 460 may communicate software commands or digital instructions regarding next steps for presenting a viewing target to a test subject or eye care patient or user of a self-service refraction instrument that includes an optical assembly configured with an adjustable sphere power and with an adjustable astigmatism power, and also in an example embodiment, with an adjustable astigmatism axis angle.
The example self service refraction apparatus illustrated in
In one example embodiment, the optical assembly is capable of providing adjustments as follows:
1. Any one of the three primary optical parameters, elements or components of human vision known as sphere, cylinder and axis, can be changed on demand; and
2. Adjustments to each of the three components can be applied to the test subject's eye to change her vision individually by component or simultaneously with more than one component of the three components.
3. Visual Acuity (VA) tests can be performed as determined by the decision module by displaying an eye chart or certain optometric symbols of varying size and/or orientation, or a PSF target, for example, as disclosed in US patent by Shui Lai, U.S. Pat. No. 8,632,184, which is incorporated by reference, to the test subject without corrective optics to test an uncorrected visual acuity (“VA”) of the test subject, or with corrective optics interposed along an optical path between an eye or eyes of the test subject and the eye chart or other suitable viewing target to determine a corrected visual acuity using a specific prescription or potential prescription. In an example embodiment, the letters of a Snellen chart may be read out loud, and voice recognition software may be used to identify what was said, and labels or tags may be applied indicating whether the letters are correctly identified. Thereby, a computer or on-board processor of a self service refraction device in certain embodiments has the ability to automatically score the visual acuity of the test subject. Voice recognition software is commercially available from Dragon Speak, and Google Voice.
A self-service subjective refraction process in accordance with certain embodiments may start, after initialization and alignment of one or both eyes of the user along the optical path of the self service refraction device, by applying the sphere, cylinder and axis values obtained from auto refraction at 250 in
The decision module 460 is programmed to select a corrective optics configuration at 330 to start the self-service subjective refraction test 300 at
Examples of a self-service subjective refraction process 140 such as the example illustrated in
If there is a previous refraction, or the readings of the current eyeglasses' prescription 320 are available, that Rx 320 is input into the computer, by either typing it, scanning into a PDF file, a camera capture of the Rx certificate and photo image upload to the PC or other on board self service refraction device processing component or an online database of optometric prescription data may be used with the test subject's consent to upload and download prescriptions from and to, respectively, remote vision services locations and perhaps different eye examination test providers. In this example embodiment, computer software code will program the processor to read the Rx values from an image of a Rx certificate. If a test subject has an eye doctor or an optometrist that he or she has worked with in the past, then on a second or other subsequent visit either in person or virtually with this same eye care specialist, the previous visual acuity test data and prescription may be available in the test subject's personal file with his or her office.
In 320 of the example process of
The test subject's visual acuity will be measured in one embodiment using a traditional Snellen chart. The decision module 460 uses the visual acuity based on the prescription 320 of the current eyeglasses or other corrective lenses, e.g., contact lenses or intraocular lenses, and the visual acuity of the auto refraction prescription 310 outcome from the wave front measurement. This forms a basis of the test subject's vision potential in the example embodiments of
In one embodiment, the computer is configured to recognize the test subject's voice, with a built in voice recognition software, wherein the computer may score the visual acuity test from the test subject's voice response. In another embodiment, the test subject's face may be recognized or the test subject's file may be accessed upon the user logging in to the self-service refraction kiosk or upon the user inserting a card and entering a pin.
A decision module 460, as illustrated in example embodiments at
In one subset of example embodiments, the decision module 460 may include and/or may be programmed in accordance with:
(a) a set of industry established refraction rules 470 provided by one or more refraction experts, wherein these rules guide the refraction process, to attend improvement in visual acuity, and in a short processing time. In an example embodiment, the sphere component is first adjusted to reach its maximum visual acuity, followed by adjustment of the cylinder power component to reach its maximum visual acuity. Then the axis component is adjusted to reach its maximum visual acuity. Based on the progression of the improvement of the visual acuity in the process, the decision module 460 may decide whether to continue to refine the individual components. The decision module 460 may determine that a continuing improvement is sufficiently likely and would be sufficiently significant, such that the user may have not reached her maximum visual acuity potential yet, and continue the self-service subjective refraction test process. Alternatively, the decision module 460 may decide to stop any further adjustment if the visual acuity level has reached a high level visual acuity, such as at 20/12 or better, or another visual acuity target such as 20/20. Alternatively even if the visual acuity is not at 20/12 or better, but the decision module 460 could conclude that the user's maximum visual acuity potential had been reached, e.g., based on comparing and contrasting data received in a current test with a library of stored reference data sets and/or by inputting current test data to one or more accepted formulae or consulting a look-up table stored within the decision module 460 and/or in an accessible database, and further adjustments would not be likely to produce meaningful improvement in the visual acuity for this user, then the decision module 460 may decide to end the test; and/or
(b) a set of learned refraction rules 470 compiled with a learning algorithm and/or Bayesian software, e.g. that may be based on a neural network trained to make decisions based on one or more of the following factors: (i) a visual acuity score at the present or current optics setting, (ii) an extent of improvement in visual acuity score between current and previous optics settings, (iii) a priority rule for selecting which of a selected subset of optic components, e.g., the three optic components of sphere, cylinder and axis, is to be tested next, based on an extent of visual acuity improvement in each of the three optical components, or alternatively based on just one or two of the sphere, cylinder and axis optical components and/or one or more additional, perhaps subtler, optical components. A decision module 460 in alternative embodiments may include (a) or (b), including any combination of (i), (ii) and (iii), or a combination of both (a) and (b).
After a decision module 460 in accordance with any of these example embodiments is sufficiently trained or otherwise equipped with a sufficient database of industry-established, expert-provided and/or learned rules, to base logical, consistent decision-making during self-administered eye tests at efficient self-service refraction kiosks, like efficient self-service banking at ATMs, the decision module 460 may be configured to make certain decisions mandated as certain logical rules-based conclusions drawn from applying the rules database 470 available to the decision module 460 to the test data which indicates the validity of those certain conclusions as being in accordance with those rules as applied to that test data. Decisions that the decision module 460 may be configured to make may include:
i. Which of the three optical components should be adjusted next? In an example, many optometrists would start with adjusting the sphere component, then the cylinder power, then the axis angle. The decision module 460 may determine to re-test one or more of the sphere, cylinder and/or axis components, particularly following testing and improvement of another component by adjusting an optical parameter of the test subject's corrected vision. The decision module 460 may determine not to test an optical component that has been determined to be optimized already or to be unlikely to improve by testing it now. The order of the testing may be different, particularly for test subject's known to have predominant cylinder or axis issues or issues with higher order aberrations;
ii. How big the change in the step size of an optical component is appropriate? Based on traditional optometric practice, the decision module 460 may determine to start a test using a starting step size of 0.25 Diopters, or 0.375 or 0.5 diopters or 0.125 or 0.0625 diopters. The decision module 460 may determine to reduce the step size after a coarse adjustment portion of a test during a refinement portion of the test to achieve better visual acuity. The decision module 460 may use a larger or smaller starting step size based, e.g., on time since a test subject's last test, or on an extent of total correction or past prescription history of the test subject, or the test subject's age or occupation or other health issues or personal or family health history, or based on test subject-specific information that suggests a different starting step size should probably be used. While generally, the step size may be mostly or only decreased throughout most tests, step size may be increased one or more times during some tests in some embodiments. The step size may be increased to a slightly larger step size than a just previous step size in most circumstances when a step size increase is determined by the decision module 460. The decision module 460 would rarely determine to increase a step size to larger than the starting step size, and would not likely do so during a refinement phase of a test, while a typical coarse adjustment phase of a test would rarely include an increase of step size to greater than the starting step size, unless the decision module 460 determines early in the test that the starting step size should have been greater than the starting step size was for this test. A test subject's pattern of choices may suggest that one or more of those choices has caused a divergence away from an optimal end point for an optical component that is being tested, such that the decision module 460 may correct for the divergence with a slightly larger step in the opposite direction. A next step size may be reduced to half or a third or a quarter or less of a current step size when the test subject indicates that a present image appears to be almost perfectly clear or optimally focused. A reduced step size may be selected based on an absolute or percentage or fractional amount of change of step size from the previous step size or on an estimated distance from an optimal end point based on past experience.
iii. When does an optical component reach its optimal point, such that no further meaningful improvement should be attempted? If the decision module 460 determines that a test subject's visual acuity has already reached 20/12 or 20/10 or another preset threshold or target vision quality, then the test may be stopped notwithstanding that no other indicators suggest that the test subject's optimal vision quality has likely been established. If the decision module 460 determines that the test subject has provided contradicting answers when prompted by the decision module 460 to make a choice between same or similar pairs of viewing targets, such that each of the contradicting answers was likely based on small perceived differences in focus and/or clarity of one viewing target over another, or was even a perceived coin flip for the test subject due to the patient's sensitivity limit having been reached or due to the optical end point being nearly half way between the two choices presented to the test subject.
iv. When to check visual acuity score before, during or after a test to determine whether or not a visual acuity score has changed a preset meaningful amount indicating that the test subject' quality of vision has been improved a sufficiently significant amount?
v. When to repeat steps (i) to (iv) until the visual acuity score has not changed by a preset meaningful amount, for example; the preset amount can be at less than two lines of letters of improvement in a visual acuity test, or it could be set at less than one line of letters of improvement. The decision module 460 can be programmed in certain embodiments to determine when the visual acuity reaches the definition of no meaningful improvement, and therefore the refraction test is finished.
Next, in an example embodiment, collected data including one or more of an Rx from autorefraction 310, a current glasses Rx 320, and their respective visual acuity scores may be input into the decision module 460 at step 330 in the example self-service refraction processes illustrated at
Several example embodiments of refraction eye tests involving objective wavefront refraction using wavefront aberrometry devices and methods and/or certain subjective refraction steps involving input from the test subject have been described in detail in U.S. Pat. Nos. 7,699,471, 10,383,512, 9,320,426, 7,726,811 and 8,366,274 and other above-referenced patents by the present inventor Shui T Lai, all of which are incorporated by reference. For example, details as to how certain adjustments may be performed in certain example embodiments in accordance with steps 330-334 of
Another example method for adjusting a sphere component in a self-service subjective refraction eye test involving a decision module 460 that takes into account objective and subjective input data in making decisions automatically based on expert learning and/or reference to a refraction rules database as part of a digital device involving sophisticated automatic processing will now be described as a next example. In certain embodiments, two presentations of a viewing target manifest two different sphere values of corrective optics through which the test subject is disposed to observe the viewing target. The difference between the two sphere values, or step size, presented to the test subject is determined by the decision module 460 based on a general strategy of gradually decreasing the differences in sphere values of the choices presented to the test subject and on a demonstrated sensitivity of the test subject to sphere value adjustments between sets of two or more viewing targets. The test subject may be asked by a voice prompt or words or other symbols on a display screen or noise prompts or vibrations, for example, to decide which one of the two or more choices is more clear, or more focused and/or which of the choices is least clear or least focused.
The test subject, who is using the self-service refraction device to help determine his or her own corrective optical prescription profile may respond by communicating a choice by voice or actuation of an input device or by typing an answer. For example, the test subject may communicate that: “choice 1 is better than 2.” Or vice versa. If choice 1 corresponds to an optical arrangement that provides a higher sphere value than that providing choice 2, then the test subject is understood to have communicated that she prefers the higher sphere value option among the previous choices, and the decision module 460 may as a result in certain embodiments move the sphere setting towards higher values at a certain step size of sphere power increments based on that subjective input from the test subject. The decision module 460 may next present two additional choices of viewing targets to the test subject corresponding to observing a viewing target through choices of optics that have different sphere powers and are configured on average to have higher sphere powers than the average of the previous choices presented to the test subject.
The process may iteratively continue, with prior choices communicated by the test subject informing the decision module 460 in determining next sphere power adjustments, in step size, in changes in step size, and/or in direction of incremental step size differences in sphere power between pairs or larger groups of three or more presented viewing targets, until in certain example embodiments the decision module 460 determines that either:
The decision module 460 may decide to stop any further investigation in sphere in this example, and instead may decide to move on to investigate cylinder or axis. The decision module 460 may be configured to change the size of the step based in part on test subject input to assist in getting to the correct, precise, accurate, improved, enhanced and/or optimized end point more efficiently in certain embodiments.
A decision module 460 in accordance with certain embodiments may be configured to determine an astigmatism correction for a test subject in accordance with any of the following example embodiments, referring specifically now to
The decision module 460 may configure an optics assembly of a self-service refraction device instrument through which the test subject will look at one or more viewing targets, which may be point-like viewing targets as in 502 of
The decision module 460 may arrange the optics assembly in a way that provides a selected spherical and astigmatism power correction to the test subject 509, based on previous and/or current test data, and on said expert refraction rules database and/or on learned or trained refraction rules, and wherein the power of the sphere 511 and power of the astigmatism 512 are both adjustable in certain example embodiments. The axis of the astigmatism 514 may also be adjustable in certain example embodiments. In the case where the test subject does not have an astigmatism issue, the decision module 460 may decide only to adjust the sphere power 510. In either case, the decision module 460 will check visual acuity 515 in both of the example embodiments illustrated at
In certain example embodiments, the two elongated shapes that are overlapped in perpendicular disposition may form a cruciform shape in
In an example embodiment, the two perpendicular lines may form a cross by extending the length of one the lines through the center of the other line, or one line may bisect the other line. The two lines may alternatively form a “T” or an “L” or the two lines may extend radially outward from a single point, or may extend radially outward from a circle of finite radius, wherein the two lines may in certain embodiments while not in others, be extrapolated into the circle as intersecting at its center. In other embodiments one or both lines are disposed tangent to the circle, and either line may be perpendicular or tangent to third arbitrarily open or closed shape having continuous curvature throughout, which may or may not change along one or more surfaces and which may have one or more discontinuities in form or curvature along a closed path or from one end to another along an open path. Further examples are provided at U.S. Pat. Nos. 10,194,796 and 10,194,794, which are incorporated by reference.
Next, the decision module 460 may continue to reduce the spherical power from the previously identified and recorded first sphere power stop point illustrated at
After the first sphere power stop point is identified and recorded as illustrated at
Now two lines perpendicular to each other are presented to the test subject, who sees the “X” shaped image 736 as crossed lines of different clarity due to the test subject's astigmatism, e.g., as illustrated by the viewing target 736 at
Next, the decision module 460 may continue to reduce the spherical power from the previously identified and recorded first sphere power stop point illustrated at
Referring now to
The automated refraction process includes finding specific end points. Some details have been provided above and thus are incorporated and not otherwise repeated here. Referring now to
The decision module 460 presents in an example embodiment a selected viewing target, e.g., a point source, for the patient to view, including a number of pixels at maximum or preset brightness intensity. The cluster of pixels preferably forms a round shape that appears as a point at a sufficiently far distance.
The test subject is ready to start, e.g., with an input device 440 in hand and with eyes aligned with an eyepiece of a self-service refraction instrument. The test subject's eyes are aligned along an optical path that includes corrective optics disposed between the test subject's eyes and the viewing target. The decision module 460 instructs the processor 410 to commence a scan to bring the point source viewing target stepwise to a more sharply focused line or point to the patient. The patient pushes a button or a trigger on an input device 440, to indicate the best image of a focused line has been reached as shown in
Next, a nesting method is used to pin point an improved value at the DCA. Based on this patient input, the decision module 460 may set, in an example embodiment, a scan range to +/−0.75D at the patient selected location at the DCA 422. For example, the patient may have picked −2.75 D. The new scan range may in an example embodiment now be −2.00D to −3.50D and the scan step size in this example may be reduced to −0.25D. This time, the patient may select −3.0D at the DCA 422. If a comparable refraction accuracy of a standard phoropter refraction procedure of 0.25 diopters is desired, one may stop here and record the sphere value for the patient. One may choose to continue to refine the accuracy to 0.125 D or even finer in a similar manner.
Each scan may involve in an example embodiment seven presentation positions at the DCA 422. At one second per step of the presentation in an example embodiment, the two scans will take about 15 seconds. The decision module 460 may decide to skip the first scan of 0.5 D step in an example embodiment if the decision module 460 is reasonably certain that the patient's refractive power has not changed beyond 0.75D.
At step 930 of
Suppose that the actual cylinder axis of the patient is 150 degrees, not 135 degrees. Short focused lines at each of the dots will be pointing at 150 degrees, however, the centers of the short lines would be aligning along 135 degrees such as those shown in
Note that the task of finding the angle of short lines in
Two cross lines of point viewing targets or short line viewing targets may be presented to a test subject. The two lines of points are pointing at 90 degrees cross, in one example, a first line is pointing at 135 degrees and a second line is perpendicular to the first line and is pointing at 45 degrees as illustrated at
The decision module 460 instructs the processor 420 to start an eye test scan using the cylinder value of the old eyeglasses −1.50D as a starting point, and setting the scan range to +/−0.75D in astigmatism diopter powers. In this example, the scan will cover from −0.75D to −2.25D in −0.25D steps. The test subject may see a shortening of focused lines initially, until the short lines turn into round, circularly symmetric balls or disks. If too much astigmatism is applied, short lines will begin to develop in the 90 degrees direction to the original short lines, i.e., in this example, the 135 degree short lines at
At the optimal point, the image as perceived by the patient, includes the points arranged in an X shape just as the viewing target at
The decision module 460 may decide to find the sharpest point at step 950 of
In a subjective refraction, the outcome derives from a combination of the eye's optics, retina function, visual pathway and the interpretive power of the brain. Defects in any one of the components can degrade the quality of vision. The preferred technique identifies the optimized vision in an efficient manner.
In one embodiment, the sensitivity of the eye test is controlled by the size and the brightness of the point source. The larger the light spot or the “point source”, the easier it is for the patient to identify end points. However, the larger the spot size, the worse is the spatial resolution and the attainable quality of vision. Therefore, an appropriate “point source” spot size is selected to attain a predetermined targeted level of quality of vision. One also controls the brightness of the presented point source to avoid saturation which may wash out details of starbursts and other features one may want to eliminate.
One may start with the assumption that 20/20 vision is achievable in a patient. One then sets the spot size to subtend a visual angle of 1 minute of arc. If the “point source” is placed at 6 meters from the patient, the object size is 1.75 mm for 1 minute of arc. One may use a slightly smaller spot size to account for diffraction and intensity saturation effects. For example, one selects a 1 mm diameter spot size point target at 6 meters for a 20/20 refraction.
If a patient undergoes the test through steps 1-4 above without too many repeated tests and delays, he or she is ready to move on to finding a better level of quality of vision. One may reduce the spot size to 0.5 mm at 6 meters for example and goes for the 20/10 vision.
On the other hand, a test subject with a cataract or macular degeneration conditions may have difficulty deciding the end points during the test steps 920-950, using a 1 mm target size and at 0.25D steps. One then increases the spot diameter to 1.5 or 2 mm or even larger until the patient can more easily identify the end points. When the spot diameter is increased to 2 mm or larger, the scan step size can also be increased from 0.25D to 0.5 D. The sensitivity reduction typically takes place at the step 920 or step 940 of
First, the steps 920-950 illustrated in
However, if the patient has healthy eyes, after standard phoropter refraction he or she still sees starbursts forming around a single point that has been corrected for sphere, cylinder and axis, and he or she desires to attain better vision, one needs to correct the higher order aberrations of the eye. In another example embodiment, at step 970 of
Next the decision module may set the scan step size to 0.01D for both DCA and ACA. The decision module may move the sphere correction to the start position at +0.25D from the final prescription after the completion of Step 4 above and at 950 of
The decision module 460 next asks the test subject to find the most symmetric shape. Basically, this means repeating step 940 of
The decision module then asks the test subject to find the sharpest point. After ACA scan is completed, the decision module 460 may decide to scan the sphere power at DCA 422 in 0.01D steps, and repeat the scan to check accuracy of the end point. Steps 940 and 950 can be repeated until the test subject confirms that starbursts have been substantially reduced or eliminated.
The decision module 460 will determine whether the final prescription will be in the increments of 0.01 diopters in both sphere and cylinder, and whether the axis angle may be in 0.5 degrees increments, or whether different increments may apply depending on the sensitivities of the test process and the eyes of the test subject.
After all three optical components have been investigated one after the other in this example embodiment, the decision module may determine that it is time now to check the visual acuity of the test subject. One purpose for checking visual acuity here is to confirm whether any improvement has been accomplished by the refraction process. If the visual acuity level has reached a predetermined level which is considered acceptable as being the final refraction outcome, the refraction is completed at 360 in
In the case of different test subjects with uncorrected eye aberrations,
In the case of a same test subject at different stages of a self-service refraction test process,
The results of a self service refraction eye test in accordance with certain embodiments may be provided to a physician or optometrist to review in a condensed form, for example, as described by the present inventor/applicant at United States patent application publication number 2020/0037868, entitled “Concise Representation for Review of a Subjective Refraction test,” which is incorporated by reference. The physician or optometrist advantageously could serve more patients because reviewing the results of the self service refraction tests in condensed representation in accordance with certain embodiments takes less of the physician's time per patient than performing each test side by side with each test subject start to finish.
Optionally, a quasi self service refraction test may be performed primarily by the test subject at a quasi self service kiosk with the supervision of a trained expert technician or optometrist being available to assist, in person or through a live chat or online telemedicine module that may be built into the quasi self service kiosk, or the expert may be available by downloading a separate app onto the test subject's mobile device, as needed. In this example embodiment, the expert may be assigned to supervise multiple quasi self service kiosks simultaneously, and may be available to assist any of several test subjects who are primarily running their own self-service eye examinations at different, proximate and/or remote, quasi-self service kiosks. Such technician may not need to be an expert optometrist or physician, but may have familiarity with the operation of the quasi self service kiosk or otherwise have a training background far less stringent than that required of a physician, optometrist or expert technician, and online support or telephone support, or a guide manual, text, audio and/or video, or other help center support may be available that is sufficient to help a test subject during an user-friendly self service refraction eye examination.
An apparatus is provided for monitoring a tilt angle of a patient's head during an ophthalmic measurement, such as a self-service refraction test by decision module in accordance with embodiments described above herein. In one example embodiment, a head tilt angle monitoring apparatus includes an electronic level sensor configured to acquire tilt angle data of a patient's head during an ophthalmic measurement. A head band, glasses, a hat, headphones, one or more ear clips, or other head gear, or combinations thereof, has the electronic level sensor coupled therewith and is configured to couple in a fixed orientation relative to an orientation of the patient's head. A communication circuit is configured to export the tilt angle data acquired by said electronic level sensor to an angle indicator.
The head band, glasses, hat, headphones, one or more ear clips, or other head gear, or combinations thereof, may be coupled to or integrated with a head phone device that is configured to produce an audio angle indicator.
The angle indicator may include (i) a computer tablet or other mobile computing device that includes a real-time digital display of said tilt angle data streaming from said electronic level sensor, or (ii) an audio speaker, ear bud, headphone device or other audio transmission device configured to provide one or more text to voice messages or other sounds in accordance with said tilt angle data streaming from said electronic level sensor, or (iii) a mobile device configured to generate text or voice message announcements at a mobile device of the patient, or (iv) combinations of these.
The communication circuit may include (i) Bluetooth or (ii) other wireless antenna or transmitter, or (iii) a hard wired or plug-in electrical connection to the angle indicator, or (iv) combinations of these.
A reference leveling device may be configured to determine an angular offset reference point to a true “vertical” orientation. In certain embodiments, when the reference leveling device indicates that it is disposed precisely horizontally, then the eyes of the patient will be disposed at a same relative height, such that neither the patient's right eye nor left eye is closer to the ground than the other. A line drawn between the centers of the patient's pupils may be approximately parallel to the long dimension of the level such that when the level determines that it is oriented horizontally then the patient's head can be relied upon to be within an acceptable tolerance deviation angle from a 0° tilt angle or upright orientation or portrait orientation. The reference leveling device may include one or more sensors that are angled at a predetermined angle to the line drawn between the patient's two pupils, wherein the predetermined angle is deemed to be a threshold at which an alarm or other communication is consciously perceivable by the self-service refraction test subject, or in an assisted refraction test by a physician, optometrist, technician, automated testing device and/or the patient herself or himself so that the patient can return to a 0° tilt angle, upright and/or portrait orientation.
In accordance with an example embodiments,
In certain embodiments, an alarm or other warning sound may include an alarm or noise or any melody or rhythmic audio clip including any number of one or more beats that may repeat at certain intervals, until corrective action is taken by the test subject 1100, e.g., to sit up straight with or without assistance to level the head. The sound may get progressively louder for as long as it takes to incentivize the test subject 1100 to take corrective action rapidly to preserve the quality and integrity of the eye measurement to achieve useful results in the form of an accurate prescription for lenses or a lasik pattern, for non-surgical eye tissue correction or for a surgical eye correction procedure. The alarm may alternatively or additionally include a vibration and/or a strobe light and/or another change in lighting or background that is easily and quickly noticeable by the test subject, even if her eyes are partly or wholly closed at the time or focused on a viewing target provided by the self-service refraction device 1140.
An eye exam which utilizes subjective and/or objective refraction techniques can be completed with reliable assurance that the test subject's head was not tilted more than the predetermined angle during the test other than perhaps for a fraction of a second about the same time that the reference level sensor determined that the angularly offset level sensor component was deemed to be parallel with horizontal. The reference leveling device may include (i) a bubble level, (ii) a laser level, (iii) a box level, (iv) a torpedo level, (v) an I-beam level, (vi) an optical level, (vii) a surveyor's level, (viii) a cross-check level or a bulls-eye level for determining that the patient's head is level with a 2D horizontal plane, or (ix) a digital or analog electronic level, (x) a pre-calibrated level device, or (iv) combinations of these or other types of levels known to those skilled experts in the use of levels.
Examples of reference leveling devices that may be coupled with a wearable earphone, earbud, head phone, helmet, hat head band, eyeglass frame, denture, tooth alignment or brace device or other dental device, wig or hair piece, tie, collar, necklace, chin rest or chin strap, respiratory filter, cloth mask, or oxygen mask, goggles, neck brace or other wearable device, include the Tacklife™ MT-LO3 12 inch level, the MD 92379 Smarttool Rail or 92500 SmartTool Gen3 Digital Level, Gummerson Tools Inclinometer or Digital Level Protractor Angle Finder, Zircon Ultra level pro, Accusize 8″ master precision level serial number #5908-C685 which may have an accuracy between 0.02″/10″ and 0.0002″/10″ or between 0.002″/10″ and 0.0002″/10″, the Tacklife MDP02 advanced digital protractor level/bevel gauge/angle gauge, Shefio's IP54 dust and waterproof electronic level tool, the Checkpoint 0300PL Pro mag precession torpedo level, Tacklife Spirit level, DOWELL 9 inch magnetic box level torpedo level which may have three different bubbles, e.g., 45°, 90°, 180° or 0°, 10°, 20°, M-D Building Products 92346 SmartTool Module, TekcoPlus angle finder ruler tool gauge and/or long digital inclinometer protractor with or without magnetic base, GemRed Digityal level Angle Slope Level, Hammerhead Digital Level with Laser, Semloss multipurpose laser level measuring tape standard and metric tape ruler, AdirPro 32x Optical Auto Level self leveling tool, Qooltek multipurpose laser level laser measure line, Stabila 29124 type 80A-2 measuring stick level, Rack-A-tiers 45404 Jet Level, Stabila 36514 type 196-2 tech 14′ level, Fitmaker angulizer ruler template tool, General Tools 828 Digital Sliding T-bevel gauge and digital protractor, PLS180 Red Cross L:ine Laser Level PLS-60521N by Pacific Laser Systems, Bosch Self-Leveling Cross Line Laser GLL-55, GLL 30, or GLL 3-80, Huepar 901CG or 902CG or box 1G professional laser level mute 150 ft. green beam cross laser self-leveling alignment tool, Goldblatt 3-piece Torpedo Spirit Level Set, Suaoki P7, Workpro WO02901A 4-piece measuring tool set, torpedo, spirit level, GemRed Digital Level angle slope (N0.420 digital torpedo level with or without magnets), Brillife laser leveler spirit level line lasers ruler, gradienter horizontal ruler, Kole GW323 multi-purpose laser level with or without suction mount, Pacific Laser Systems PLS 180, Navegando 5 line 6 point 360° rotary multipurpose self-leveling output 4 vertical, Johnson level and tool 40-6648 self leveling cross and line laser, URCERI 9211R line and plumb self-leveling horizontal, vertical cross line, YOUTHINK laser measuring device with Pythagorean mode, measure distance, area and volume, Leico disto e7500i, DEWALT DW03050 laser distance measurer, LESHP Handheld laser distance measure, Perfect-Prime RF0350 Diastimeter, and/or Fnova splash and dust proof distance measure, or combinations of two or more thereof.
The tilt angle data may include an angular offset reference to a true vertical orientation, such that the angle indicator receives or communicates, or both, a deviation angle from the true vertical orientation.
A warning alarm circuit or app may be configured to trigger communication of a warning alarm signal when the tilt angle data indicates a deviation angle from the true vertical orientation that exceeds a predetermined angular limit.
In an embodiment configured so that a test subject 1100 may self-correct his or her head orientation embodiment, the angle indicator may be configured to receive tilt angle data and to communicate to the patient in real time a beep sound, or a voice message announcement or other audio, visual or other sensory warning signal when the tilt angle data indicates a deviation angle from a true vertical orientation that exceeds a predetermined angular limit. A feedback mechanism may be configured to guide the test subject to correct his or her head tilt angle, in response to the warning signal, back to an optimum head alignment position during an self-service eye measurement procedure.
An angle indicator may receive and/or communicate tilt angle data calibrated to an angular offset from a true vertical orientation of the test subject's head. In another embodiment that is configured so that a test subject may self-correct his or her head orientation, the angle indicator may be configured to receive tilt angle data and to communicate to the test subject in real time a beep sound, or a voice message announcement or other audio, visual or other sensory warning signal when the tilt angle data indicates that a deviation angle from an angular offset orientation exceeds a predetermined angular limit, wherein the angular offset orientation may differ by the angular offset from the true vertical orientation. In this embodiment, a feedback mechanism may be configured to guide the test subject 1100 to correct his or her head tilt angle in response to the warning signal back to the angular offset orientation as an optimum head alignment position during an eye measurement procedure.
A method of monitoring a tilt angle of a patient's head during an ophthalmic measurement is also provided. The method includes coupling an electronic level sensor 1120 in a fixed orientation relative to an orientation of a test subject's head. Tilt angle data of the test subject's head may be acquired during an ophthalmic measurement in an example embodiment. The tilt angle data acquired by an electronic level sensor 1120 coupled to head gear 1110 may be exported to an angle indicator in an example embodiment.
The electronic level sensor 1120 may be coupled to a head band, glasses, hat, headphones, one or more ear clips, a face shield or face mask, or other head gear, or combinations of, that may be coupled to a patient's head during an eye measurement. The electronic level sensor 1120 may be coupled onto or integrated with a head phone device that is configured to produce an audio angle indicator.
The exporting of the tilt angle data to the angle indicator may include streaming the tilt angle data from the electronic level sensor 1120 to the angle indicator.
The exporting of the tilt angle data to the angle indicator may include Bluetooth or other wireless transmission or transmission over a hard-wired or plug-in electrical connection, or combinations of these.
An angular offset reference point to a true vertical orientation may be determined. The determining of the angular offset reference point may involve utilizing (i) a bubble level, (ii) a laser level, or (iii) a pre-calibrated level device, or (iv) combinations of these.
The tilt angle data may include an angular offset reference to a true vertical orientation, such that the exporting of the tilt angle data to the angle indicator may include exporting the deviation angle from the true vertical orientation along with the tilt angle data and/or exporting deviation angle-adjusted tilt angle data.
The method may include triggering a warning alarm signal when the tilt angle data indicates a deviation angle from the true vertical orientation that exceeds a predetermined angular limit. The method may include communicating to the patient in real time a beep sound, or a voice message announcement or other audio, visual or other sensory warning signal when the tilt angle data indicates a deviation angle from a true vertical orientation that exceeds a predetermined angular limit. The method may further include guiding the patient to correct his or her head tilt angle in response to the warning signal back to an optimum head alignment position during an eye measurement procedure.
The method may include indicating the tilt angle in real time during an eye measurement. The indicating of the tilt angle in real time may include (i) displaying said tilt angle on a computer tablet or other mobile computing device, or (ii) generating one or more text or voice messages or other sounds in accordance with said tilt angle data at an audio speaker, ear bud, headphone device or other audio transmission device, or (iii) generating on a mobile device of the patient text or voice message announcements, or (iv) combinations of these. The indicating may include receiving and/or communicating tilt angle data calibrated to an angular offset from a true vertical orientation of the patient's head.
The method may include communicating to the patient in real time a beep sound, or a voice message announcement or other audio, visual or other sensory warning signal when the tilt angle data indicates that a deviation angle from an angular offset orientation exceeds a predetermined angular limit, wherein the angular offset orientation may differ by the angular offset from a true vertical orientation. The method may include guiding the patient to correct his or her head tilt angle in response to one or more further sensory signals back to the angular offset orientation as an optimum head alignment position during an eye measurement procedure.
Another method and apparatus are provided that are configured for head orientation self-correction by an eye measurement patient during an eye measurement. In the method, a tilt angle of a patient's head is monitored during an eye measurement procedure. A beep sound or a voice message or other audio, visual, vibratory or other sensory warning signal is generated and communicated to the patient during the eye measurement warning the patient that his or her head is tilting at least a certain predetermined angular limit amount. One or more further sensory signals and produced and communicated to the patient to guide the patient to correct his or her head orientation and thereby maintain his or her head orientation within said certain predetermined angular limit amount during the eye measurement.
The method may involve generating and communicating a sensory warning signal that includes controlling sound volume based on amount of head tilt angle. The controlling of the sound volume may include increasing sound volume as head orientation deviates farther from true vertical orientation or from an offset orientation which was set as a reference point.
The method may involve generating and communicating a sensory warning signal that includes controlling a beep frequency based on amount of head tilt angle. The controlling of the beep frequency may include increasing the beep frequency as the head orientation deviates farther from true vertical orientation or from an offset orientation which was set as a reference point.
The method may involve generating and communicating a sensory warning signal that includes controlling an intensity of a visual and/or vibratory warning signal based on amount of head tilt angle. The controlling of the visual and/or vibratory intensity may include increasing sound intensity as head orientation deviates farther from a true vertical orientation or from an offset orientation which was set as a reference point.
In an apparatus, means for patient self-correction of head orientation during an eye measurement are provided. The apparatus includes means for monitoring a tilt angle of the patient's head during an eye measurement procedure; means for generating a beep sound or a voice message or other audio, visual, vibratory or other sensory warning signal to the patient during said eye measurement warning the patient that her head is tilting at least a certain predetermined angular limit amount; and means for producing one or more further sensory signals to the patient to guide the patient to correct her head orientation and thereby maintain her head orientation within said certain predetermined angular limit amount of tilting of her head during the eye measurement.
The apparatus may include means for generating and communicating a sensory warning signal that includes means for controlling sound volume based on amount of head tilt angle. The means for controlling sound volume may include means for increasing sound volume as head orientation deviates farther from true vertical orientation or an offset orientation which was set as a reference point.
The apparatus may include means for generating and communicating a sensory warning signal that includes means for controlling a beep frequency based on amount of head tilt angle. The means for controlling beep frequency may include means for increasing the beep frequency as the head orientation deviates farther from true vertical orientation or from an offset orientation which was set as a reference point.
The apparatus may include means for generating and communicating a sensory warning signal that includes means for controlling an intensity of a visual or vibratory warning signal, or both, based on amount of head tilt angle. The means for controlling an intensity of a visual and/or vibratory warning signal may include means for increasing sound intensity as head orientation deviates farther from true vertical orientation or from an offset orientation which was set as a reference point.
The eye has certain muscles that cause the eye to move side to side in horizontal direction and up and down direction without moving the head. However, there is no muscle in the eye that may cause the eye to rotate along the optical axis of the eye. Hence vision correction using eyeglasses is based on a stationary position of the glasses resting on patient's nose and with temples resting over the patient's ears. Likewise, a refractive surgery makes refractive power changes on the cornea or in the stroma of the eye, as in LASIK, or PRK or corneal on lay or inlay procedures. Whether it is a vision correction by eyeglasses, or by laser surgery, the corrective powers are determined prior to the making of the corrective lenses in the case of eyeglasses, or prior to applying the laser tissue ablation pattern to the eye. Multiple example embodiments are provided of refraction measurement methods and equipment that are configured such that the axis angle of the astigmatic correction is reliably aligned with the axis of a corrective tool, such as a pair of glasses, or an ablation pattern orientation provided by a refractive surgery. Therefore if the patient's eye or head is tilted during an axis measurement, such as a refraction measurement, undesirable residual refractive errors may likely result from the treatment.
An electronic level sensor may include an accelerometer, a gyrometer, a bubble level, a laser level, or an optical face or head orientation device including a camera, a processor and a software application for determining a face or head orientation of an eye patient and/or changes in face or head orientation.
Head gear can include anything that may be configured to couple to an eye patient's head and/or to couple in fixed relative orientation with an eye patient's head such as attachment at the top of the neck or an unattached or quasi-attached device that responds in known proportion to changes in an eye patient's head orientation.
Communication circuits may include electronic, magnetic and/or optical components, digital or analog, with or without a processor and/or software app that may generate and/or communicate signals that include tilt angle data and/or data that is representative of the tilt angle data. Communication circuits or one or more components thereof may include an angle indicator or one or more components thereof.
An angle indicator may communicate or relay a sensory signal to an eye patient that includes an audio, visual, and/or touch sensory signal, and/or even a smell or taste signal and/or a cognitive signal that includes tilt angle data and/or data that is representative of the tilt angle data. An angle indicator may or may not receive tilt angle data and may or may not communicate tilt angle data and may communicate to the patient, another person and/or a machine capable of effecting real time patient head tilt angle correction.
In accordance with another example embodiment, a motorized mechanism is provided for adjusting an optical assembly automatically in a self-service refraction test in accordance with an example embodiment. Referring now to instrument that is schematically illustrated at
In one embodiment, two pinion gears are used. One pinion gear 1360 may be used to drive both bevel gears, as illustrated in
A motor unit 1370 illustrated in
Outer rings of ball bearings 1330 and a corresponding outer ring for the second ball bearing are attached to inner rings of third and fourth ball bearings. The outer rings of the third and the fourth ball bearings are in turn supported and mounted to the base of the instrument (not shown). The outer ring of the fourth bearing 1390 is shown in
Instead of using pinion gears to drive the two wave plates of the ACA 1320, which are preferably substantially identical, in opposite direction, at identical angular rates or otherwise in identical angular amounts per increment, one may use synchronized motor drives. In such construction, each wave plate is driven by its own driver electronics. However, two driver circuits are controlled by a closed loop algorithm, such that the two motors still move substantially in “lock-step”, or move continuously or jog in steps, in substantially identical angle increments in the same or opposite directions, during any commanded movement. The motor movement is monitored by rotatory encoder. An amplitude precision greater than 0.01 diopters is in this way achievable in a 6 diopter astigmatism adjustable wave plate unit.
Indeed,
Equipment and methods for performing a refractive eye measurement and/or for determining and/or correcting aberrations of human eyes that may be combined within alternative and/or additional embodiments are described at U.S. Pat. Nos. 6,706,036, 6,325,792, 6,761,454, 9,408,533, 9,320,426, 9,247,871, 8,684,527, 8,632,183, 8,632,184, 8,950,865, 8,967,801, 8,790,104, 8,409,177, 8,388,137, 8,366,274, 8,262,220, 8,113,658, 8,033,664, 7,954,950, 7,909,461, 7,824,033, 7,699,471, 7,726,811, 7,695,134, 7,490,940, 7,461,938, 7,425,067, 7,293,871, 7,220,255, 7,114,808, 5,984,916 and 5,549,632, and at US published application no. 2005/0174535, and each of these patents and published patent applications is hereby incorporated by reference.
While an exemplary drawings and specific embodiments of the present invention have been described and illustrated, it is to be understood that that the scope of the present invention is not to be limited to the particular embodiments discussed. Thus, the embodiments shall be regarded as illustrative rather than restrictive, and it should be understood that variations may be made in those embodiments by workers skilled in the arts without departing from the scope of the present invention.
In addition, in methods that may be performed according to preferred embodiments herein and that may have been described above, the operations have been described in selected typographical sequences. However, the sequences have been selected and so ordered for typographical convenience and are not intended to imply any particular order for performing the operations, except for those where a particular order may be expressly set forth or where those of ordinary skill in the art may deem a particular order to be necessary.
A group of items linked with the conjunction “and” in the above specification should not be read as requiring that each and every one of those items be present in the grouping in accordance with all embodiments of that grouping, as various embodiments will have one or more of those elements replaced with one or more others. Furthermore, although items, elements or components of the invention may be described or claimed in the singular, the plural is contemplated to be within the scope thereof unless limitation to the singular is explicitly stated or clearly understood as necessary by those of ordinary skill in the art.
The presence of broadening words and phrases such as “one or more,” “at least,” “but not limited to” or other such as phrases in some instances shall not be read to mean that the narrower case is intended or required in instances where such broadening phrases may be absent. The use of the term “apparatus” does not imply that the components or functionality described or claimed as part of the assembly are all configured in a common package. Indeed, any or all of the various components of an apparatus, e.g., head gear and angle indicator may be combined in a single package or separately maintained and may further be manufactured, assembled or distributed at or through multiple locations.
This application is a continuation in part (CIP) of PCT/US20/18712, filed Feb. 18, 2020, which claims the benefit of priority to U.S. provisional patent application No. 62/806,911, filed Feb. 18, 2019. Each of these priority patent applications is incorporated by reference. This application is related to U.S. Pat. Nos. 10,383,512, 10,194,796, 10,194,794, 9,955,867, 9,743,829, 9,730,578, 9,408,533, 9,320,426, 9,247,871, 8,967,801, 8,950,865, 8,790,104, 8,753,551, 8,684,527, 8,636,359, 8,632,184, 8,632,183, 8,409,177, 8,388,137, 8,366,274, 8,262,220, 8,113,658, 8,066,359, 8,033,664, 7,954,950, 7,909,461, 7,824,033, 7,748,844, 7,726,811, 7,699,471, 7,695,134, 7,490,940, 7,461,938, 7,425,067, 7,420,743, 7,293,871, 7,234,810, 7,220,255, 7,114,808, 7,114,415, 6,761,454, 6,706,036, 6,325,792, 6,210,401, and 5,549,632, which are incorporated by reference.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/US20/48304 | 8/27/2020 | WO |
| Number | Date | Country | |
|---|---|---|---|
| Parent | PCT/US2020/018712 | Feb 2020 | US |
| Child | 17800532 | US |
