A method for measuring incommunicable strabismus based on virtual reality and eye tracking technology

Abstract

The present invention discloses a non-common strabismus diagnosis method based on virtual reality and eye tracking technology, and the non-common strabismus diagnosis method includes the following steps: S1 determining the dominant eye and the strabismus eye; S2 circumferential rapid testing; S3 custom point detection. The non-common strabismus diagnosis method can solve the problems that the traditional detection process is cumbersome and time-consuming, has high requirements on the professional quality and experience of doctors, and the detection results are greatly affected by the subjective factors of doctors, so as to achieve the purpose of being easy to use, fast, scientific and objective, and the detection process is largely automated, and more accurate detection is completed in a shorter time. In combination with a variety of strabismus degree measurement methods, the detection process is carried out in stages, taking into account the qualitative understanding of the overall situation of the non-common strabismus of the tested person and the need for accurate measurement of specific points, and making a gaze direction-strabismus degree polar coordinate diagram to further effectively present the overall situation of the non-common strabismus of the tested person.

Description

Technical Field

[0001] The present invention relates to the technical fields of strabismus diagnosis, virtual reality and eye tracking, and in particular to a non-common strabismus measurement method based on virtual reality and eye tracking technology. Background Art

[0002] Virtual reality technology, also known as virtual environment, uses computer simulation to create a three-dimensional virtual world, providing users with simulations of vision and other senses, allowing users to feel as if they are in the real world and observe things in the three-dimensional space instantly and without restrictions. When the user moves, the computer can immediately perform complex calculations and send back accurate three-dimensional world images to create a sense of presence. This technology integrates the latest developments in computer graphics, computer simulation, artificial intelligence, sensing, display and network parallel processing, and is a high-tech simulation system generated with the assistance of computer technology.

[0003] Eye tracking technology refers to the tracking of eye movements by measuring the position of the eye's gaze point or the movement of the eye relative to the head. An eye tracker is a device that can track and measure the position of the eye and eye movement information. It is widely used in the study of visual systems, psychology, and cognitive linguistics. There are currently many methods for eye tracking, the most commonly used non-invasive method is to obtain the position of the eye through a video camera. Invasive methods include embedding an eye movement measurement coil in the eye or using microelectrodes to record the electrooculogram.

[0004] Currently, in clinical practice, strabismus diagnosis mainly relies on ophthalmologists using point light sources and lenses and other tools. Specific methods include corneal reflection method, alternating cover method, prism cover method, etc. On the one hand, the traditional detection process requires high professional quality and experience of the tester, and the test results will be greatly affected by the tester's subjective factors; on the other hand, the detection process often requires good cooperation from the testee, which is a big challenge for the diagnosis and treatment of strabismus in children; in addition, the traditional detection process is relatively cumbersome and time-consuming, especially for non-common strabismus detection involving multiple eye positions. Summary of the invention

[0005] In view of the above technical problems in the related art, the present invention proposes a non-common strabismus measurement method based on virtual reality and eye tracking technology, which can overcome the above shortcomings of the prior art.

[0006] To achieve the above technical objectives, the technical solution of the present invention is implemented as follows:

[0007] A method for measuring incommensurate strabismus based on virtual reality and eye tracking technology comprises the following steps:

[0008] S1 Determine the dominant eye and the strabismus eye: Place a target object in front of the subject's field of vision in the VR scene, and ask the subject to look at the target object. After the subject's gaze is determined to be stable, use the alternating cover method to determine the dominant eye and measure the accurate strabismus degree of the first eye position:

[0009] S11 first ensures that the test subject can see the target object normally in both eyes of the VR field of view. After the gaze direction vectors of both eyes are stable, take the gaze direction vector of the left eye for n frames and calculate the average value to obtain the gaze direction vector of the left eye before covering.

[0010] S12 covers the right eye VR field of view, while keeping the left eye VR field of view unchanged. After the left eye gaze direction vector stabilizes again, take the direction vector of n frames, calculate the average value and get the gaze direction vector of the left eye after covering. and get and The angle Δθ between them;

[0011] S13 reference and The difference between the left eye and the right eye is adjusted to adjust the relative angle of the left eye's VR field of view before and after covering the right eye's VR field of view. Repeat the experiment until Δθ is less than the set threshold ε. At this time, the relative angle of the left eye’s VR field of view before and after covering the right eye’s VR field of view The left eye squint degree δ 左 , the corresponding angle adjustment direction is its squint direction;

[0012] S14 measures the right eye in a symmetrical way between S11 and S13 to obtain the right eye strabismus degree δ 右 ;

[0013] S15 Comparison of left eye strabismus δ 左 and right eye strabismus degree δ 右 The size of the eye with the smaller strabismus is the dominant eye, and the eye with the larger strabismus is the strabismus.

[0014] S2 circumferential quick test:

[0015] After determining the dominant eye and the strabismus eye, S21 sets the motion trajectory of the target object in the VR scene to be a circle, and the plane where the circle is located is perpendicular to the line connecting the center of the circle and the center of the connecting line between the two eyes of the subject, and the target object remains stationary initially;

[0016] S22 requires the subject to gaze at the target object, with the gaze direction of the dominant eye as the basis for judgment. Whenever the gaze direction of the dominant eye intersects with the target object, the current position of the target object is recorded, and the strabismus degree of the strabismus eye is determined by combining the data obtained by the eye tracking device. At the same time, the target object is moved along a preset circular trajectory by an angle δ, so as to measure the strabismus degree of the strabismus eye at the next position.

[0017] S23 repeats the operation in S22 until the target object moves to the initial position again, and collects the gaze direction and the corresponding strabismus degree of the strabismus eye measured in each gaze direction in the entire circumference;

[0018] S3 custom point detection:

[0019] After determining the dominant eye and the strabismus eye, S31 sets several custom points in the VR field of view;

[0020] S32 places the target objects at the respective defined positions in turn, and requires the subject to look at the target objects, with the gaze direction of the dominant eye as the basis for judgment. Whenever the gaze direction of the dominant eye intersects with the target object, the gaze direction and the current position of the target object are recorded, and the data obtained by the eye tracking device are used to determine the degree of strabismus of the strabismus eye.

[0021] Furthermore, in the S2 circumferential rapid test, after collecting a set of data pairs of gaze direction and strabismus degree, a gaze direction-strabismus degree polar coordinate diagram is produced with the gaze direction as the polar angle and the strabismus degree as the polar diameter.

[0022] Furthermore, when there are many custom points in the S3 custom point detection and the custom points are all on the same circumference, a gaze direction-squint degree polar coordinate diagram is prepared with the gaze direction as the polar angle and the squint degree as the polar diameter.

[0023] Beneficial effects of the present invention: The non-common strabismus measurement method based on virtual reality and eye tracking technology of the present invention can solve the problems that the traditional detection process is relatively cumbersome and time-consuming, has high requirements on the professional quality and experience of doctors, and the detection results are greatly affected by the subjective factors of doctors, thereby achieving ease of use, speed, science and objectivity, and realizing a large degree of automation in the detection process, completing higher-precision detection in a shorter time, combining a variety of strabismus degree measurement methods, and the detection process is carried out in stages, taking into account the qualitative understanding of the overall situation of the non-common strabismus of the test subject and the need for accurate measurement of specific points, and making a gaze direction-strabismus degree polar coordinate diagram to further effectively present the overall situation of the non-common strabismus of the test subject. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0025] Figure 1 It is a schematic diagram of a polar coordinate diagram of gaze direction-strabismus degree according to a non-common strabismus measurement method based on virtual reality and eye tracking technology described in an embodiment of the present invention. DETAILED DESCRIPTION

[0026] The following will be combined with the accompanying drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field belong to the scope of protection of the present invention.

[0027] The non-common strabismus measurement method based on virtual reality and eye tracking technology according to an embodiment of the present invention comprises the following steps:

[0028] S1 Determine the dominant eye and the strabismus eye: Place a target object in front of the subject's field of vision in the VR scene, and ask the subject to look at the target object. After the subject's gaze is determined to be stable, use the alternating cover method to determine the dominant eye and measure the accurate strabismus degree of the first eye position:

[0029] S11 first ensures that the test subject can see the target object normally in both eyes of the VR field of view. After the gaze direction vectors of both eyes are stable, take the gaze direction vector of the left eye for n frames and calculate the average value to obtain the gaze direction vector of the left eye before covering.

[0030] S12 covers the right eye VR field of view, while keeping the left eye VR field of view unchanged. After the left eye gaze direction vector stabilizes again, take the direction vector of n frames, calculate the average value and get the gaze direction vector of the left eye after covering. and get and The angle Δθ between them;

[0031] S13 reference and The difference between the left eye and the right eye is adjusted to adjust the relative angle of the left eye's VR field of view before and after covering the right eye's VR field of view. Repeat the experiment until Δθ is less than the set threshold ε. At this time, the relative angle of the left eye’s VR field of view before and after covering the right eye’s VR field of view The left eye squint degree δ 左, the corresponding angle adjustment direction is its squint direction;

[0032] S14 measures the right eye in a symmetrical way between S11 and S13 to obtain the right eye strabismus degree δ 右 ;

[0033] S15 Comparison of left eye strabismus δ 左 and right eye strabismus degree δ 右 The size of the eye with the smaller strabismus is the dominant eye, and the eye with the larger strabismus is the strabismus.

[0034] S2 circumferential quick test:

[0035] After determining the dominant eye and the strabismus eye, S21 sets the motion trajectory of the target object in the VR scene to be a circle, and the plane where the circle is located is perpendicular to the line connecting the center of the circle and the center of the connecting line between the two eyes of the subject, and the target object remains stationary initially;

[0036] S22 requires the subject to gaze at the target object, with the gaze direction of the dominant eye as the basis for judgment. Whenever the gaze direction of the dominant eye intersects with the target object, the current position of the target object is recorded, and the strabismus degree of the strabismus eye is determined by combining the data obtained by the eye tracking device. At the same time, the target object is moved along a preset circular trajectory by an angle δ, so as to measure the strabismus degree of the strabismus eye at the next position.

[0037] S23 repeats the operation in S22 until the target object moves to the initial position again, and collects the gaze direction and the corresponding strabismus degree of the strabismus eye measured in each gaze direction in the entire circumference;

[0038] S3 custom point detection:

[0039] After determining the dominant eye and the strabismus eye, S31 sets several custom points in the VR field of view;

[0040] S32 places the target objects at the respective defined positions in turn, and requires the subject to look at the target objects, with the gaze direction of the dominant eye as the basis for judgment. Whenever the gaze direction of the dominant eye intersects with the target object, the gaze direction and the current position of the target object are recorded, and the data obtained by the eye tracking device are used to determine the degree of strabismus of the strabismus eye.

[0041] In the above-mentioned S2 circumferential rapid test, after collecting the data pairs of gaze direction and strabismus degree, a gaze direction-strabismus degree polar coordinate diagram is made with the gaze direction as the polar angle and the strabismus degree as the polar diameter, as shown in Figure 1 shown.

[0042] When there are many custom points in the above-mentioned S3 custom point detection and the custom points are all on the same circumference, a gaze direction-squint degree polar coordinate diagram is prepared with the gaze direction as the polar angle and the squint degree as the polar diameter.

[0043] In order to facilitate understanding of the above technical solutions of the present invention, the above technical solutions of the present invention are described in detail below through specific usage methods.

[0044] During specific use, the tester opens the relevant test software, the testee puts on the VR helmet, calibrates the line of sight, and then starts the test. After that, the tester completes the setting of test-related parameters through the software interactive page and controls the start and end of each test. During the test, the testee needs to look at the target object in the VR scene. The main test process and the output of results are completed automatically by the program.

[0045] In summary, with the help of the above-mentioned technical scheme of the present invention, it is possible to solve the problems that the traditional detection process is cumbersome and time-consuming, has high requirements on the professional quality and experience of doctors, and the detection results are greatly affected by the subjective factors of doctors, so as to achieve easy-to-use, fast, scientific and objective, and the detection process is automated to a large extent, and more accurate detection can be completed in a shorter time. In combination with a variety of strabismus degree measurement methods, the detection process is carried out in stages, taking into account the qualitative understanding of the overall situation of the non-common strabismus of the tested person and the need for accurate measurement of specific points, and making a gaze direction-strabismus degree polar coordinate diagram to further effectively present the overall situation of the non-common strabismus of the tested person.

[0046] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for measuring non-common strabismus based on virtual reality and eye tracking technology, characterized in that: The following steps are involved: S1 Determine the dominant eye and the strabismus eye: Place a target object in front of the subject's field of vision in the VR scene, and ask the subject to look at the target object. After the subject's gaze is determined to be stable, use the alternating cover method to determine the dominant eye and measure the accurate strabismus degree of the first eye position: S11 first ensures that the test subject can see the target object normally in both eyes of the VR field of view. After the gaze direction vectors of both eyes are stable, take the gaze direction vector of the left eye for n frames and calculate the average value to obtain the gaze direction vector of the left eye before covering. S12 covers the right eye VR field of view, while keeping the left eye VR field of view unchanged. After the left eye gaze direction vector stabilizes again, take the direction vector of n frames, calculate the average value and get the gaze direction vector of the left eye after covering. and get and The angle Δθ between them; S13 reference and The difference between the left eye and the right eye is adjusted to adjust the relative angle of the left eye's VR field of view before and after covering the right eye's VR field of view. Repeat the experiment until Δθ is less than the set threshold ε. At this time, the relative angle of the left eye’s VR field of view before and after covering the right eye’s VR field of view The left eye squint degree δ 左 , the corresponding angle adjustment direction is its squint direction; S14 measures the right eye in a symmetrical way between S11 and S13 to obtain the right eye strabismus degree δ 右 ; S15 Comparison of left eye strabismus δ 左 and right eye strabismus degree δ 右 The size of the eye with the smaller strabismus is the dominant eye, and the eye with the larger strabismus is the strabismus. S2 circumferential quick test: After determining the dominant eye and the strabismus eye, S21 sets the motion trajectory of the target object in the VR scene to be a circle, and the plane where the circle is located is perpendicular to the line connecting the center of the circle and the center of the connecting line between the two eyes of the subject, and the target object remains stationary initially; S22 requires the subject to gaze at the target object, with the gaze direction of the dominant eye as the basis for judgment. Whenever the gaze direction of the dominant eye intersects with the target object, the current position of the target object is recorded, and the strabismus degree of the strabismus eye is determined by combining the data obtained by the eye tracking device. At the same time, the target object is moved along a preset circular trajectory by an angle δ, so as to measure the strabismus degree of the strabismus eye at the next position. S23 repeats the operation in S22 until the target object moves to the initial position again, and collects the gaze direction and the corresponding strabismus degree of the strabismus eye measured in each gaze direction in the entire circumference; S3 custom point detection: After determining the dominant eye and the strabismus eye, S31 sets several custom points in the VR field of view; S32: placing the target objects at the defined positions in turn, requiring the subject to gaze at the target objects, using the gaze direction of the dominant eye as a basis for judgment, and recording the gaze direction and the current position of the target object whenever the gaze direction of the dominant eye intersects with the target object, and combining the data obtained by the eye tracking device to determine the degree of strabismus of the strabismus eye; During specific use, the tester opens the relevant test software, the testee puts on the VR helmet, calibrates the line of sight, and then starts the test. After that, the tester completes the setting of test-related parameters through the software interactive page and controls the start and end of each test. During the test, the testee needs to look at the target object in the VR scene. The main test process and the output of results are completed automatically by the program.

2. The method for measuring non-common strabismus according to claim 1, characterized in that: In the S2 circumferential rapid test, after collecting a set of data pairs of gaze direction and strabismus degree, a gaze direction-strabismus degree polar coordinate diagram is produced with the gaze direction as the polar angle and the strabismus degree as the polar diameter.

3. The method for measuring non-common strabismus according to claim 1, characterized in that: When there are many custom points in the S3 custom point detection and the custom points are all on the same circumference, a gaze direction-squint degree polar coordinate diagram is prepared with the gaze direction as the polar angle and the squint degree as the polar diameter.

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