CN113080836A

CN113080836A - Non-center gazing visual detection and visual training equipment

Info

Publication number: CN113080836A
Application number: CN202110344622.6A
Authority: CN
Inventors: 杜煜
Original assignee: Shanghai Qingyan Technology Co ltd
Current assignee: Shanghai Qingyan Technology Co ltd
Priority date: 2021-03-31
Filing date: 2021-03-31
Publication date: 2021-07-09

Abstract

The invention provides a visual detection device which is characterized by comprising a display module; the image shooting and processing module comprises at least 2 near-infrared cameras and at least 2 near-infrared light sources; the central fixation eye Kappa angle calculation module is used for calculating to obtain the Kappa angle of the A eye, wherein the Kappa angle of the A eye is an included angle between the central foveal vision line of the yellow spots of the A eye and the central line of the pupil of the A eye; and the non-central gazing deviation angle calculation module is used for calculating to obtain a pupil midline of the B eye and a macular fovea centralis sight line of the B eye, and further calculating to obtain a non-central gazing deviation angle of the B eye. The invention further provides vision training equipment. The invention has the beneficial effects that: the visual detection and visual training equipment provided by the invention has the advantages that the detection result of non-central watching is objective and accurate, the visual training content is rich, and the training state and effect can be monitored in real time.

Description

Non-center gazing visual detection and visual training equipment

Technical Field

The invention relates to the field of ophthalmic medical instruments, in particular to non-center gazing vision detection and vision training equipment.

Background

The human eye is a delicate optical imaging organ. When the human eye looks at foreign objects, light rays emitted by the object enter the eyeball from the pupil of the human eye and are imaged on the retina. The fovea is a depressed area located in the center of the macular region of the retina, and is about 1.5mm to 2mm in diameter. The fovea centralis the most acute visual part of the retina, the macular region is the central vision, and the retina outside the macular region is the peripheral vision. When an object is imaged in the fovea, vision is most sensitive, and the farther the imaging is from the fovea, the less sensitive the vision.

The use of foveal fixation is called central fixation. Some subjects have central depression of macula due to strabismus or abnormal eye development, and use retina outside central fovea to replace central fovea, which is called non-central fixation (eccentricic or non-foveolar fibrosis). Non-central fixation can be classified into a foveal fixation (parafoveal fixation), a macular fixation (paramacular fixation), a peripheral fixation (periperally anchoring fixation), and a wandering fixation (wandering fixation) according to the location of the retinal fixation point. The traditional examination method of fixation property is a speculum examination, and when fixation is carried out, the relative positions of an imaging point of retina and macular fovea are 0-1 degrees for central fixation, 2-3 degrees for parafoveal fixation, 4-5 degrees for paramacular fixation (also called macular parafixation), and 5 degrees for peripheral fixation.

Non-central fixations, which are imaged outside the fovea, often result in non-central fixative amblyopia (also known as off-central fixative amblyopia), which may cause diplopia or confusion for some people. Therefore, the method has important clinical significance for performing visual detection and visual training on non-central fixation and reconstructing normal central fixation.

The traditional examination method for non-central fixation is a speculum examination, which requires subjective estimation of the non-central fixation position, and is not easy to quantitatively and accurately measure, and young children are not easy to cooperate in examination.

The traditional vision training methods for non-central fixation are as follows: masking, afterimage therapy, red filter therapy, Haidinger brushing therapy, and the like. The training content is single, children are not easy to insist on training, and the effect of the training is not easy to monitor and evaluate in real time.

Disclosure of Invention

The purpose of the invention is: a vision detection and vision training apparatus is provided that may be used for non-central gazes.

In order to achieve the above object, a technical solution of the present invention is to provide a visual inspection apparatus, which is characterized in that one of two eyes is a central fixation eye, which is called an a eye, and the other eye is a non-central fixation eye, which is called a B eye, and the apparatus includes:

a display module;

the image shooting and processing module comprises at least 2 near-infrared cameras and at least 2 near-infrared light sources and is used for continuously shooting images of the eye area; the image shooting and processing module also comprises an image processing function, and the image processing function is used for carrying out image processing calculation on the shot image of the area; when an A eye image is shot, the image shooting and processing module obtains three-dimensional coordinates of the center of a pupil of the A eye and the center of each cornea reflection point of the A eye through an image processing function; when a B eye image is shot, the image shooting and processing module obtains a three-dimensional coordinate of the center of a pupil of the B eye and three-dimensional coordinates of the centers of all cornea reflecting points of the B eye through an image processing function; the relative positions of the image shooting and processing module and the display module are fixed and known;

the central fixation eye Kappa angle calculation module defines the central foveal vision of the yellow spots of the A eyes as a straight line passing through the central fovea of the yellow spots of the A eyes and the center of pupils of the A eyes, and the central foveal vision of the yellow spots of the A eyes is intersected with the fixation position of the A eyes when the A eyes fix foreign objects; the central fixation eye Kappa angle calculation module controls the display module to display the sighting target T which can be seen by only A eyes at the specified position_aThe examinee gazes at the optotype T_aThen, the central foveal line of the macula of the A eye passes through the center of the pupil of the A eye and the visual target T_aA straight line of (a); the central fixation eye Kappa angle calculation module calculates the three-dimensional coordinates of the pupil center of the eye A and the three-dimensional coordinates of the centers of all cornea reflection points of the eye A to obtain the eye ACalculating to obtain the Kappa angle of the eye A, wherein the Kappa angle of the eye A is the included angle between the foveal vision of the macula lutea of the eye A and the pupil center line of the eye A;

the non-center gaze deviation angle calculation module defines the abnormal sight of the B eye as a straight line passing through the center of the pupil of the B eye and the gaze position when the B eye gazes at a foreign object; defining the foveal vision of the macula lutea of the B eye as a straight line passing through the fovea macula of the B eye and the center of the pupil of the B eye; the non-central gazing deviation angle calculation module controls the display module to display the sighting target T which can be seen by only B eyes at the designated position_bThe examinee gazes at the optotype T_bThen, the abnormal visual line of the B eye passes through the center of the pupil of the B eye and the visual target T_bA straight line of (a); the non-central gaze deviation angle calculation module calculates three-dimensional coordinates of a pupil center of the B eye and three-dimensional coordinates of each cornea reflection point center of the B eye to obtain a pupil center line of the B eye and a macular central foveal vision of the B eye, and further calculates to obtain a non-central gaze deviation angle of the B eye, wherein the non-central gaze deviation angle of the B eye is an included angle between an abnormal visual line of the B eye and the macular central foveal vision of the B eye, and the non-central gaze deviation angle of the B eye is calculated by the non-central gaze:

the non-central gaze deviation angle calculation module obtains a foveal vision of macular of the B eye in the following mode;

according to the principle of physiological symmetry of the left eye and the right eye, the included angle between the central foveal vision of the macula lutea of the B eye and the central line of the pupil of the B eye is equal to the Kappa angle of the A eye in size, the included angle is in mirror symmetry with the median sagittal plane of a human body in direction, and therefore the central foveal vision of the macula lutea of the B eye is obtained by the non-central gaze deviation angle calculation module through calculation based on the Kappa angle of the A eye obtained by the central gaze eye Kappa angle calculation module.

Preferably, the device further comprises a judging module, which is used for calculating an included angle between a foveal vision line of a macula lutea of the B eye and an abnormal vision line of the B eye when the B eye monocular is staring at the sight; and when the included angle between the central concave vision of the macula lutea of the B eye and the abnormal vision of the B eye is a stable value within a period of time, the judgment module judges that the B eye is stably and non-centrally watched.

Preferably, the device further comprises a judging module, which is used for calculating an included angle between a foveal vision line of a macula lutea of the B eye and an abnormal vision line of the B eye when the B eye monocular is staring at the sight; and when the included angle between the central concave sight of the macula lutea of the B eye and the abnormal sight of the B eye is an unstable value within a period of time, the judgment module judges that the B eye is wandering non-central gazing.

Another technical solution of the present invention is to provide a visual inspection apparatus, which is called a B eye by setting one of two eyes as a non-central fixation eye, and the known B eye is a stable non-central fixation eye, and the visual inspection apparatus includes:

the display module is used for displaying the content which can be seen by only B eyes, and the other eye of the content displayed by the display module can not be seen;

the image shooting and processing module comprises at least one camera and can continuously shoot images containing B eye areas;

the eye movement point calculation module is used for obtaining a calibration function of the B eye through single-eye calibration of the B eye, and further calculating to obtain a B eye movement point coordinate according to the B eye image and the B eye calibration function, wherein when the single-eye calibration is carried out on the B eye, the eye movement point calculation module controls the display module to display a calibration visual target which can be seen by only the B eye;

a non-central gaze deviation angle calculation module:

after the calibration of the B eye is finished, the non-central gazing deviation angle calculation module controls the display module to display a first sighting mark visible only for the B eye; after the examinee watches the first sighting mark, the non-central watching deviation angle calculation module obtains a first sight line, and a connecting line of the pupil center of the eye B and the first sighting mark is defined as the first sight line;

the non-central gazing deviation angle calculation module controls the display module to display a second visual target at a position around the first visual target, wherein the position is variable within a 1-10-degree radius visual angle; the examinee responds to whether the second sighting mark can be seen at the same time when watching the first sighting mark; when the second sighting target can be seen most clearly, the non-central watching deviation angle calculation module obtains a second sight line, and the second sight line is defined as a connecting line between the center of the pupil of the eye B and the display position of the second sighting target at the moment;

the non-central watching deviation angle calculation module calculates a non-central watching deviation angle based on the first sight line and the second sight line, and the non-central watching deviation angle is an included angle between the first sight line and the second sight line; meanwhile, the eye movement point calculation module monitors the eye movement point B of the examinee in real time, if the eye movement point B leaves the position displayed by the first sighting target, the position of the first sighting target is moved in real time to be equal to the position of the eye movement point B, the display position of the second sighting target is moved, and the relative position of the second sighting target and the first sighting target is kept unchanged; or setting the test result invalid during the period that the eye movement point of the B eye leaves the first sighting mark position, and carrying out the test again.

the visual evoked potential calculating module is used for wearing a visual evoked potential device on the head of a detected person and recording the visual evoked potential of the detected person;

a non-central gaze deviation angle calculation module:

after the calibration is finished, the non-central gazing deviation angle calculation module controls the display module to display the visual target which is only visible for B eyes, the non-central gazing deviation angle calculation module obtains a first sight line after the visual target is gazed by the examinee, and the first sight line is defined as the first sight line which is the connecting line of the pupil center of the B eyes and the visual target;

the non-central watching deviation angle calculation module controls the display module to display periodic flickering light spots at variable positions within a 1-10-degree radius visual angle around the sighting target; the visual evoked potential calculating module records the visual evoked potential and corresponds to the position displayed by the flashing light spot; recording the display position of the scintillation light spot at the moment when the amplitude of the visual evoked potential is maximum, obtaining a second sight line by the non-central watching deviation angle calculation module by utilizing the recorded display position of the scintillation light spot, and defining the second sight line as a connecting line between the center of a pupil of the eye B and the display position of the scintillation light spot at the moment;

the non-central watching deviation angle calculation module calculates a non-central watching deviation angle based on the first sight line and the second sight line, and the non-central watching deviation angle is an included angle between the first sight line and the second sight line; meanwhile, the eye movement point calculation module monitors the tested eye movement point B in real time, if the eye movement point B leaves the position of the sighting target, the position of the sighting target is moved in real time to be equal to the position of the eye movement point B, the display position of the flickering light spot is moved, and the display position of the flickering light spot and the relative position of the sighting target are kept unchanged; or setting the test result invalid during the period that the eye movement point of the B eye leaves the visual target position, and carrying out the test again.

Another technical solution of the present invention is to provide a vision training apparatus, wherein one of two eyes is a non-central fixation eye, which is called as a B eye, and the B eye is known to be stable non-central fixation and a non-central fixation deviation angle is known, the apparatus comprising:

the macular center foveal vision intersection point calculating module defines the abnormal sight of the B eye as a straight line passing through the center of the pupil of the B eye and the eye moving point of the B eye; the macular foveal vision intersection point calculation module can calculate to obtain a B-eye macular foveal vision line according to the B-eye abnormal vision line and the non-central gaze deviation angle, and further calculate to obtain a B-eye macular foveal vision line intersection point, wherein the B-eye macular foveal vision line intersection point is the intersection point of the B-eye macular foveal vision line and the display plane;

a training module: during visual training, the training module controls the display module to display a clear image near the intersection point of the central foveal vision line of the macula lutea of the B eye obtained by the macular central foveal vision line intersection point calculation module, and does not display the image or display a suppressed image at the position of the eye moving point of the B eye.

Preferably, in the training module, during visual training, the training module controls the display module to display a clear image near the intersection of the foveal vision line in the macula lutea of the B eye, and when the intersection of the foveal vision line in the macula lutea of the B eye moves, the position displayed by the image moves along with the movement; and displaying no image at other positions of the display plane of the display module.

Preferably, in the training module, during visual training, the image display range does not exceed a circular range with the central concave sight intersection of the macula lutea of the B eye as the center of a circle and a radius of a viewing angle less than or equal to 2 degrees.

Preferably, in the training module, during the visual training, the display module displays a clear image near the intersection of the foveal vision line of the macula of the B eye, displays a depressed image in a region far away from the intersection of the foveal vision line of the macula of the B eye, and the position of the image display does not move along with the movement of the intersection of the foveal vision line of the macula of the B eye.

Preferably, in the training module, when the training module controls the display module to display the image, the range of displaying the clear image does not exceed the circular range of the viewing angle with the radius less than or equal to 2 degrees, taking the intersection point of the foveal vision of the macula lutea of the B eye as the center of a circle.

a training module for controlling the display module to display an image P at the intersection of the abnormal visual line of the B eye and the display plane during visual training₁Displaying an image P at the intersection of the foveal vision line of the macula of the B eye and the display plane₂(ii) a Under the condition of keeping the position of the eye moving point of the B eye unchanged, the training module gradually increases the image P₁And (5) the degree of depression, and performing visual training.

Preferably, in the training module, the image P₁And image P₂The display range is not more than the circular range of the visual angle with the radius less than or equal to 2 degrees.

Another technical solution of the present invention is to provide a vision training apparatus, one of two eyes is a central fixation eye, called a-eye, and knowing a Kappa angle of the a-eye, the other eye is a non-central fixation eye, called a B-eye, characterized by comprising:

the display module is used for displaying the content which can be seen by only B eyes, and the other eye can not be seen;

the image shooting and processing module comprises at least 2 near-infrared cameras and at least 2 near-infrared light sources and can continuously shoot images of B eyes; the system comprises an image processing function, and can perform image processing calculation on the shot image of the area to obtain three-dimensional coordinates of the pupil center of the eye B and the center of each cornea reflection point of the eye B, wherein the relative positions of the image shooting and processing module and the display module are known;

the yellow spot central concave sight intersection point calculating module is used for calculating three-dimensional coordinates of a pupil center of the B eye and three-dimensional coordinates of centers of all cornea reflection points of the B eye to obtain a pupil center line of the B eye and a yellow spot central concave sight line of the B eye, and further calculating to obtain a yellow spot central concave sight intersection point of the B eye, wherein the yellow spot central concave sight intersection point of the B eye is the intersection point of the yellow spot central concave sight line of the B eye and a display plane;

the macula lutea fovea vision intersection point calculating module obtains the macula lutea fovea vision of the B eye by adopting the following method:

according to the principle of physiological symmetry of the left eye and the right eye, the included angle between the central concave line of the macula lutea of the B eye and the pupil center line of the B eye is equal to the Kappa angle of the A eye in size, the included angle is in mirror symmetry with the median sagittal plane of a human body in direction, and therefore the macula lutea central concave line intersection calculation module calculates the macula lutea central concave line of the B eye based on the Kappa angle of the A eye and the pupil center line of the B eye;

and the training module displays a clear image near the intersection point of the fovea center of the macula of the B eye and does not display an image or display a suppressed image in other areas during visual training.

Preferably, the image is displayed at the intersection of the foveal vision of the macula lutea of the B eye, and when the intersection of the foveal vision of the macula lutea of the B eye moves, the position displayed by the image moves along with the intersection; no image is displayed elsewhere on the display plane.

Preferably, in the training module, when the image is displayed on the display module, the range of displaying the clear image does not exceed the circular range of the viewing angle with the radius less than or equal to 2 degrees and taking the intersection point of the foveal vision of the macula lutea of the B eye as the center of a circle.

Another technical solution of the present invention is to provide a vision training apparatus, which is characterized in that one of two eyes is a central fixation eye, which is called an a eye, and the other eye is a non-central fixation eye, which is called a B eye, wherein the B eye is known to be stable non-central fixation and the non-central fixation deviation angle is known, and the apparatus includes:

the display module can display an image which can be seen by only a left eye and a right eye;

the image shooting and processing module comprises at least one camera and can continuously shoot images comprising an A eye area and a B eye area;

the eye movement point calculating module is used for calculating to obtain an eye movement point coordinate A and an eye movement point coordinate B, wherein:

when the coordinates of the eye movement point A are calculated, the eye movement point calculation module is used for obtaining a calibration function of the eye A through single eye calibration of the eye A, and further calculating the coordinates of the eye movement point A according to the eye image A and the calibration function of the eye A, wherein the coordinates of the eye movement point A are the intersection point of a central foveal vision line of the yellow spot of the eye A and a display plane, and when the single eye calibration of the eye A is carried out, the eye movement point calculation module controls the display module to display a calibration sighting mark which can be seen by only the eye A;

when the coordinates of the eye movement point of the B eye are calculated, the eye movement point calculation module is used for obtaining a calibration function of the B eye through monocular calibration of the B eye and further calculating the coordinates of the eye movement point of the B eye according to the image of the B eye and the calibration function of the B eye, wherein when monocular calibration is carried out on the B eye, the eye movement point calculation module controls the display module to display a calibration sighting mark which can be seen by only the B eye;

the macular center foveal vision intersection point calculating module defines the abnormal sight of the B eye as a straight line passing through the center of the pupil of the B eye and the eye moving point of the B eye; the macular center foveal vision intersection point calculation module calculates to obtain a B-eye macular center foveal vision line according to the B-eye abnormal vision line and the non-center gaze deviation angle, and further calculates to obtain a B-eye macular center foveal vision line intersection point, wherein the B-eye macular center foveal vision line intersection point is the intersection point of the B-eye macular center foveal vision line and the display plane;

a training module for controlling the display module to display the image P visible only to A eye during visual training_A(ii) a Trainee gazing image P_AThen, the training module controls the display module to display an image P visible only for B eyes at the intersection of the foveal vision line of the macula lutea of the B eyes and the display module_B(ii) a The training module then controls the display module to hold the image P_AAnd image P_BAnd displaying at the same time, and performing visual training.

Preferably, in the training module, the image P is used for visual training_AAnd image P_BAre complementary images that need to be viewed simultaneously to form a complete image.

Preferably, in the training module, the image P is used for visual training_AAnd image P_BAre images of the same shape and size.

Preferably, in the training module, the image P is used for visual training_AAnd image P_BThe stereoscopic image has binocular parallax.

Preferably, in the training module, the image P_AAnd image P_BThe display range is not more than the circular range of the visual angle with the radius less than or equal to 2 degrees.

Preferably, the image P is such that when the intersection of the foveal vision line of the macula of the B eye changes_BThe position of the eye B is moved along with the eye B, and is always positioned at the intersection point of the foveal vision of the macula lutea of the eye B.

the image shooting and processing module comprises at least 2 near-infrared cameras and at least 2 near-infrared light sources, and can continuously shoot images of B eyes; the image shooting and processing module further comprises an image processing function, and the image shooting and processing module performs image processing calculation on the shot image of the area through the image processing function to obtain three-dimensional coordinates of the pupil center of the eye B and three-dimensional coordinates of the centers of all cornea reflection points of the eye B;

the macular fovea vision line calculation module is used for calculating three-dimensional coordinates of the pupil center of the B eye and the three-dimensional coordinates of the centers of all cornea reflection points of the B eye to obtain the pupil center line of the B eye and the macular fovea vision line of the B eye;

the macular foveal vision line calculation module obtains the macular foveal vision line of the B eye by adopting the following modes:

according to the principle of physiological symmetry of the left eye and the right eye, the included angle between the central foveal vision of the macula lutea of the B eye and the pupil center line of the B eye is equal to the Kappa angle of the A eye in size, the included angle direction is in mirror symmetry with the median sagittal plane of a human, and therefore the central foveal vision of the macula lutea of the B eye is calculated by the central foveal vision calculating module based on the Kappa angle of the A eye and the pupil center line of the B eye to obtain the central foveal vision of the macula;

the liquid crystal shielding module is a liquid crystal lens positioned in the field range of the eye B, controls the liquid crystal lens to be transparent in a certain range at and near the intersection of the central foveal vision of the macula lutea of the eye B and the liquid crystal lens, and controls other areas to be opaque for visual training, and the position of the transparent area can change in real time along with the change of the central foveal vision of the macula lutea and is always positioned at the intersection of the central foveal vision of the macula lutea of the eye B and the liquid crystal lens; the relative positions of the liquid crystal shielding module and the image shooting and processing module are fixed and known.

Preferably, in the liquid crystal shielding module, the transparent range of the liquid crystal shielding module is not more than the circular range of the viewing angle with the radius less than or equal to 2 degrees and taking the intersection point of the central concave line of sight of the yellow spots of the B eyes as the center of a circle.

Preferably, the vision training device may be integrated in a head-mounted apparatus, the head-mounted apparatus being a pair of head-mounted glasses, a VR device, or an AR device.

The invention has the beneficial effects that: the visual detection and visual training equipment provided by the invention has the advantages that the detection result of non-central watching is objective and accurate, the visual training content is rich, and the training state and effect can be monitored in real time.

Drawings

FIG. 1(a) is a schematic view of the foveal line of the right eye of the first embodiment; FIG. 1(b) is a schematic illustration of the Kappa angle for the right eye; FIG. 1(c) is a schematic diagram of an abnormal line of sight for the left eye; FIG. 1(d) is a schematic diagram of the calculation of the foveal line of the left eye macula from the left eye pupillary midline;

FIG. 2 is a schematic diagram showing the positions of the components of the apparatus according to the first embodiment;

FIG. 3 is a schematic diagram showing the relative positions of the display, 2 cameras, 2 light sources, and left and right eyes according to the first embodiment;

FIG. 4 is a schematic diagram illustrating a three-dimensional positioning principle of a pupil center by a dual-camera system according to an embodiment;

FIG. 5 is a schematic diagram illustrating a principle of calculating a pupil center line according to an embodiment;

FIG. 6 is a diagram showing the display positions of the icons according to the second embodiment;

FIG. 7 is a schematic diagram illustrating a calculation method of the intersection of the foveal vision of the macula in the fourth embodiment.

Detailed Description

The invention will be further illustrated with reference to the following specific examples. It should be understood that these examples are for illustrative purposes only and are not intended to limit the scope of the present invention. Further, it should be understood that various changes or modifications of the present invention may be made by those skilled in the art after reading the teaching of the present invention, and such equivalents may fall within the scope of the present invention as defined in the appended claims.

Example one

For a normal central fixation eye, when fixation is made to a foreign object, the light rays from the foreign object pass through the center of the pupil and are imaged in the fovea at the macula. In the invention, the central fixation eye 'macular foveal vision' is defined as a straight line passing through the central fovea of the central fixation eye and the center of the pupil, the central fixation eye 'macular foveal vision' extends to the outside of the eyeball and intersects with the fixation position of the central fixation eye when the central fixation eye fixates on a foreign object. For normal central fixation, "foveal vision at the macula" is the visual axis.

For non-central fixation eyes, when fixation is made to a foreign object, the foreign object cannot be imaged in the fovea maculae. The non-central fixation eye 'macular foveal vision' is defined as a straight line passing through the fovea of the macula of the non-central fixation eye and the center of the pupil, and the non-central fixation eye 'macular foveal vision' extends to the outside of the eyeball and cannot intersect with the fixation position when a foreign object is fixed.

For example: one subject had a central fixation on the right eye and a non-central fixation on the left eye.

As shown in FIG. 1(a), since the right eye is the center of the eye, the optotype T on the display module is observed with the single eye of the right eye_aWhen the eye is right, the eye passes through the fixation point (visual target T)_aPosition of) and the right eye pupil center P_rIntersects the retina of the right eye at the fovea maculae (M)_rThe location of (d).

As shown in fig. 1(b), the dotted line is the median of the pupil of the right eye of this subject. The central line of the pupil is the axis of symmetry of human eyes, most people have an included angle formed by incomplete coincidence of the central foveal vision of the macula and the central line of the pupil, and the included angle formed by the central foveal vision of the macula and the central line of the pupil is called a Kappa angle. The Kappa angle alpha of the right eye of the subject is the angle between the foveal line of the macula lutea of the right eye and the midline of the pupil of the right eye.

As shown in FIG. 1(c), the subject's left eye is in non-central gaze, and the optotype T on the display module is in monocular gaze with the left eye_bWhen passing through the left eye fixation point (optotype T)_bPosition of) and left-eye TONG-hole center P_lThe intersection of the straight line and the left eye retina is Y_lNot in the fovea of the left eye_lIn the position of (a). In the present invention, we define the "abnormal line of sight" of a non-center-fixation eye as a straight line passing through the center of the non-center-fixation eye's TONG-hole and the location where the eye fixates on foreign objects. The imaging point of the abnormal sight line of the non-central fixation eye on the retina is an abnormal retina imaging point. In FIG. 1(c), T_b、P_l、Y_lThe line connecting these three points is an abnormal line of sight for the left eye. Meanwhile, the foveal line of the left eye macula lutea, namely a straight line passing through the fovea of the left eye macula lutea and the center of the left eye pupil, intersects with the display module at C_lAnd (4) point.

According to the principle of physiological symmetry of the left eye and the right eye, the included angle beta between the central foveal line of the macula of the left eye and the pupil center line of the left eye is equal to the Kappa angle alpha of the right eye, and the included angle directions are mirror symmetry with the median sagittal plane of a human body (the human body is symmetrical left and right with the median sagittal plane). Therefore, as shown in FIG. 1(d), let us say that the pupillary midline of the subject's left eye is known (dotted line in the figure), and that the Kappa of the subject's right eye is knownThe size and direction of the angle, also known as the median sagittal plane of the head, the angle β between the foveal line of the macula of the left eye and the midline of the pupil of the left eye is known, and the foveal line of the macula of the left eye can be obtained. If the relative positions of the left eye and the display module are known, the intersection C of the foveal line of the left eye and the display module_lThe position of the point may also be known.

As shown in fig. 2, the visual inspection apparatus provided in this embodiment includes a display module, an image capturing and processing module, a central gazing eye Kappa angle calculation module, and a non-central gazing deviation angle calculation module. Wherein, the display module is a display 1. The system also comprises an electronic computer 2, and an image processing algorithm of the image shooting and processing module, a central fixation eye Kappa angle calculation module and a non-central fixation deviation angle calculation module are all programs running on the electronic computer 2. In addition, the present embodiment further includes a determination module, which is also a program running on the electronic computer 2, and can determine the type of the non-center gaze. The present embodiment also includes a head fixation support 3.

In this embodiment, the image capturing and processing module includes 2 near-infrared cameras, which are a left camera and a right camera, respectively, and 2 near-infrared LED point light sources with a light emitting wavelength of 850nm, which are a left light source and a right light source, respectively, and are located outside the near-infrared cameras. The image capture and processing module is located below the display 1, and the camera and light source are housed in the housing. Each eye can be captured by 2 near infrared cameras in the image capture and processing module. The relative positions between the 2 near-infrared cameras, the 2 near-infrared light sources and the display 1 are fixed and the relative positions are known. The relative position relationship of the display 1, the left camera 4-1, the right camera 4-2, the left light source 7-1, the right light source 7-2, the left eye 5 and the right eye 6 in the image shooting and processing module is shown in fig. 3.

The operation of the equipment comprises the following specific steps:

the examinee sits in front of the equipment, the eyes face to the display 1, the chin of the examinee is placed on the head fixing support 3, the left eye and the right eye are the same in height, and the left eye and the right eye are the same in distance from the display 1. Two near infrared cameras 4-1, 4-2 in the image capture and processing module can capture images containing the eye area.

(II) calculating central foveal vision of macular of central fixation eye

As shown in fig. 4, the optotype T is displayed on the display 1_aVisual target T_aA small dot, located in the center of the display 1.

In this step, only the right eye of the central fixation eye can see the optotype T_a. The manner in which the optotype is made visible to only one eye may be one of the following: (1) covering the other eye with an eye patch; (2) using a polarized display while the subject wears polarized glasses; (3) displaying an image visible only to a single eye using a naked eye 3D display; (4) using a stereoscopic shutter display while shutter glasses are worn by the subject; (5) the examinee wears glasses such as red-green glasses with different color lenses for both eyes, and the display 1 correspondingly displays an image composed of colors visible only for one eye.

In the embodiment, the eyeshade is used for shielding the left eye, so that only the right eye can see the sighting mark T_aLet the examinee watch the optotype T_a. The binocular camera system formed by the left camera 4-1 and the right camera mechanism 4-2 can calculate the three-dimensional space coordinates based on the parallax information of the same object. Pupil center P of right eye_rThree-dimensional space coordinate P_rThe (x, y, z) calculation method is as follows:

as shown in FIG. 4, the three-dimensional space coordinate uses the optical center E of the left camera 4-1 as the origin, the straight line of the connecting line EI from the optical center of the left camera 4-1 to the optical center of the right camera 4-2 is the X-axis, the straight line of the optical axis EH of the left camera 4-1 is the Z-axis, and the Y-axis is perpendicular to the XZ plane (not shown in the figure).

The distance between the left camera 4-1 and the right camera 4-2 is T, F is the center of the imaging plane of the left camera 4-1, and J is the center of the imaging plane of the right camera 4-2. Center of pupil P_rThe imaging point on the left camera 4-1 is G and the imaging point on the right camera 4-2 is K. Because the size of the imaging plane of the camera is known, the X-axis distance between a certain imaging point and the center of the imaging plane is easy to calculate. The distance between the G point and the F point projected in the X-axis direction is GF, and the K point and the J point in the X-axis direction can be calculatedThe distance on the projection is JK.

Let EF ═ IJ ═ f.

Obtaining an equation (r) and an equation (c) according to a similar triangle principle as follows:

because the equations (r) and (r) have only two unknown quantities x and z, and the other values GF, JK, f, T are known, the solution can be found:

in the same way, according to the pupil center P_rThe distance between the imaging point and the center of the imaging plane in the Y-axis direction (the distance is Δ Y) is used to determine the pupil center P_rY-coordinate of (c):

thus the pupil center P_rThe three-dimensional space coordinates of (a) are calculated.

And because the relative positions of the left and right cameras and the display are fixed, i.e. the optotype T_aIs known, so that T_aAnd the pupil center P of the right eye_rThe three-dimensional space connecting line can be determined to be a straight line where the foveal vision of the macula lutea of the right eye is located.

(III) calculating the pupil midline of the right eye by the central gazing eye Kappa angle calculating module

The outer side of the pupil has a spherical corneal surface. The outer surface of the cornea of the human eye is regarded as a convex mirror, and the point light source forms a virtual image on the other side of the convex mirror through the reflection of the convex mirror. Based on optical imaging principles, it is known that the position of the virtual image is determined by the position of the light source and the convex mirror, independent of the position of the observer (i.e. independent of the position of the camera). In addition, a spatial straight line formed by connecting the point light source and the virtual image passes through the spherical center of the spherical surface where the convex mirror is located.

As shown in fig. 5, the subject is allowed to watch the optotype T with his right eye_aBased on the optical principle of point light source convex mirror reflection imaging and the binocular vision principle, the three-dimensional space position of two near-infrared point light sources is set to be R₁And R₂The three-dimensional position R of two near-infrared reflection point virtual images on the outer surface of the cornea can be calculated₁' and R₂′。R₁-R₁' connection and R₂-R₂The connecting line of the' intersects with the spherical center O of the spherical surface on which the outer surface of the cornea is positioned_c. In addition, the pupil center P has been measured in the previous step_rThree-dimensional coordinates of (a). P_rAnd O_cIs the right eye pupil midline.

(IV) the center fixation eye Kappa angle calculation module calculates the Kappa angle of the right eye

And calculating the included angle between the foveal vision of the yellow spots of the right eye and the central line of the pupils of the right eye to obtain the angle of the Kappa angle of the right eye. In this embodiment, the foveal line of the right eye is on the midline nasal side of the right eye pupil (relative position of the outer part of the eyeball) and has an included angle of 2 °, i.e., the Kappa angle of the right eye is 2 °.

(V) the non-central gazing deviation angle calculation module calculates the non-central gazing deviation angle of the left eye

The right eye is shielded and the left eye is exposed, and the left eye is a non-central fixation eye. Display 1 shows optotype T_bAt this time, only the left eye can see the optotype T_bIn this embodiment, the visual mark T_bA small dot in the center of the display 1. Let examinee's left eye watch sighting target T_bThe three-dimensional space coordinate of the center of the pupil of the left eye can be measured by the binocular camera, and the sighting mark T is calculated_bConnecting the left eye pupil center to obtain the left eyeThe abnormal line of sight of (2).

The pupil center line of the left eye can be calculated by a method similar to the calculation of the pupil center line of the right eye.

According to the principle of physiological symmetry of the left eye and the right eye, the included angle between the central foveal vision of the macula of the left eye and the pupil midline of the left eye is equal to the Kappa angle of the right eye, and the included angle directions are in mirror symmetry with the median sagittal plane of a human body. In this embodiment, since the height of the left and right eyes of the subject is the same and the distance between the left and right eyes and the display is the same, the midsagittal plane is perpendicular to the ground and perpendicular to the line connecting the two eyes, and it can be seen that the foveal line of the left eye macula is on the nasal side of the midline of the pupil of the left eye (relative position of the outer part of the eyeball) and the included angle is 2 °.

And then calculating the included angle between the abnormal sight of the left eye and the foveal sight of the macula lutea center of the left eye to obtain the non-center watching deviation angle of the left eye. For example, in the present embodiment, the abnormal line of sight of the left eye is measured on the temporal side of the pupillary midline of the left eye (relative position outside the eyeball), and the included angle is 3 °, so in the present embodiment, the non-central gaze deviation angle of the left eye of the subject is 2 ° +3 ° -5 °, and the direction is the temporal side of the abnormal line of sight of the left eye on the foveal line of the left eye macula (relative position outside the eyeball). Inside the eyeball, the left-eye abnormal retinal image point is at a position 5 ° to the foveal side of the left-eye macula lutea center.

(VI) determination of non-center gaze type

Let examinee's left eye monocular continue to watch on sighting target T_bFor a period of time, this example is 10 seconds. During this time, the non-central gaze deviation angle of the left eye is continuously recorded.

And if the non-central fixation deviation angle is a stable value, judging that the type of the left-eye non-central fixation is stable non-central fixation. Stable non-central fixation means that when the eye fixates on a fixed position of the target, the target's imaging point on the retina is a fixed point, but because this point is not on the fovea, it is called an abnormal retinal imaging point.

And if the non-central fixation deviation angle is an unstable value, judging that the type of the left-eye non-central fixation is wandering non-central fixation. Wandering off-center fixation means that when the eye fixates on a fixed position of the target, the point of the target's image on the retina does not settle at a fixed point.

Example two

One subject, whose left eye is known to be in non-central fixation, has qualitatively detected the relative position of the abnormal retinal image point of the left eye and the fovea macula to be fixed by conventional means (such as a speculum), i.e., "stable non-central fixation" as mentioned in the first embodiment. But the non-central watching deviation angle is difficult to be accurately and quantitatively judged by traditional modes such as a film examination mirror and the like. The visual detection equipment provided by the embodiment of the invention can accurately and quantitatively detect the non-central gazing deviation angle.

A visual detection device comprises a display module, an image shooting and processing module, an eye movement point calculating module and a non-central gazing deviation angle calculating module. The system also comprises an electronic computer, and an image processing algorithm of the image shooting and processing module, an eye movement point calculating module and a non-central gazing deviation angle calculating module are programs running on the electronic computer. In addition, the equipment also comprises a head fixing device, the chin of the examinee is placed on the head fixing device, the distance between the head fixing device and the display module is fixed and known, and therefore the distance between the eyes of the examinee and the display is also fixed and known.

And the display module is a display, and the displayed content can be seen by the left eye only and cannot be seen by the right eye. The right eye can be shielded by an eye mask, or the right eye can be shielded by a polarized display, a naked-eye 3D display and the like mentioned in the first embodiment.

And the image shooting and processing module comprises at least one camera and can continuously shoot images comprising the left eye area. In this embodiment, the image capturing and processing module includes 1 near-infrared camera and 2 LED near-infrared point light sources with a light emitting wavelength of 850nm, the 2 near-infrared light sources are located at two sides of the near-infrared camera, and the near-infrared camera and the near-infrared light sources are placed in a casing of the image capturing and processing module. The relative positions of the image capture and processing module and the display are fixed and known.

The specific steps of the operation of the equipment are as follows:

the subject sits in front of the apparatus, with his chin on the head mount, and his eyes facing the display, and the eyes being sixty cm from the display. And a near-infrared camera in the image shooting and processing module continuously shoots images containing a left eye area, and calculates the pupil center and the cornea reflection point center of the left eye in real time (taking the average coordinate of two cornea reflection points as the cornea reflection point center) to obtain a left eye pupil cornea vector.

(II) calculating the eye movement point by the eye movement point calculating module

In the embodiment, a single-camera system is used, and a mapping relation between a pupil cornea vector (two-dimensional) and a display plane eye movement point coordinate (two-dimensional) in a shot image, namely a calibration function, is obtained through multi-point calibration.

Sequentially displaying the calibration sighting marks at N different positions on the display, wherein N is more than or equal to 2 and less than or equal to 9; and substituting the pupil cornea vector and the calibration sighting mark coordinate when the left eye looks at the calibration sighting mark into a calibration mapping function equation set, and solving the left eye calibration mapping function coefficient to obtain a left eye calibration function. In this embodiment, taking a 9-point calibration as an example, the calibration optotype is a 9-point at the center, left, right, up, down, left up, right up, left down, and right down of the display, and the positions of the 9 points are known and determined. The 9-point scaling procedure for the left eye is as follows:

let x_sIs the abscissa, y, of the eye movement point on the display plane_sIs the ordinate of the eye movement point on the display plane; x is the number of_eIs the value of the horizontal direction of the pupil corneal vector, y_eThe pupil-cornea vector is a value in the vertical direction of the pupil-cornea vector, which is acquired from the camera image and has a unit of pixel.

The following mapping function is used:

a₀、a₁、a₂、a₃、a₄、a₅、b₀、b₁、b₂、b₃、b₄、b₅these 12 values are unknown prior to calibration. The first stage of calibration is the process of solving for these 12 unknowns.

Because the coordinates (x) of the 9 calibration targets on the display plane_s1,y_s1)、(x_s2,y_s2)、(x_s3,y_s3)、(x_s4,y_s4)、(x_s5,y_s5)、(x_s6,y_s6)、(x_s7,y_s7)、(x_s8,y_s8)、(x_s9,y_s9) Are known; the pupil cornea vectors can be calculated by the image shooting and processing module when the 9 calibrated sighting marks are seen to be (x)_e1,y_e1)、(x_e2,y_e2)、(x_e3,y_e3)、(x_e4,y_e4)、(x_e5,y_e5)、(x_e6,y_e6)、(x_e7,y_e7)、(x_e8,y_e8)、(x_e9,y_e9). Substituting the mapping function (r) can obtain an equation set (c) consisting of the following 18 equations:

because the equation number is larger than the number of unknown variables, the overdetermined equation set needs to be solved according to the least square method to obtain the least square solution a₀、a₁、a₂、a₃、a₄、a₅、b₀、b₁、b₂、b₃、b₄、b₅。

Because a is₀、a₁、a₂、a₃、a₄、a₅、b₀、b₁、b₂、b₃、b₄、b₅All are solved into known values, and the pupil angle obtained by the image shooting and processing moduleHorizontal direction value x of film vector_eAnd the vertical value y of the pupil corneal vector_eSubstituting the mapping function to obtain the horizontal coordinate x of the eye movement point on the display plane_sAnd the ordinate y of the eye movement point on the display plane_s。

After the calibration is performed by using the steps, the calibration function of the left eye is obtained. And the eye movement point calculation module substitutes the left eye calibration mapping function according to the left eye pupil cornea vector obtained by the image shooting and processing module, and then the eye movement point coordinate of the left eye can be calculated.

(III) the non-central gazing deviation angle calculation module calculates the non-central gazing deviation angle of the left eye

After the left-eye monocular calibration is finished, the display displays a first visual target at the center of the display, and displays a second visual target at a position around the first visual target, wherein the position is variable within a 1-10-degree radius visual angle, and the content, the size and the resolution of the second visual target can be set. In this embodiment, the first visual target is a "+" character, and the second visual target is an "E" character with a 1 ° viewing angle with random opening directions. In this embodiment, the second optotype is displayed at a variable position within a radius of view of 1 ° to 10 ° around the first optotype, and the second optotype may be sequentially displayed at sequential positions or random positions at grid points spaced by 1 ° in each of the longitudinal and lateral directions, and all the position points at which the second optotype can be displayed are as shown in fig. 6 (the "+" character in the middle of the circle is the position at which the first optotype is displayed). In the embodiment, the display is sequentially performed from left to right and from top to bottom, and the positions of every two times are not repeated. The examinee needs to use the left eye to watch the first sighting mark, and the line connecting the center of the pupil of the left eye and the first sighting mark is a first sight line; the examinee responds to whether the second sighting mark can be seen at the same time when watching the first sighting mark, and the responding mode is any one of oral report, action instruction, key pressing, mouse operation and the like. In the embodiment, the examinee verbally reports the opening direction of the E word mark, if the examinee cannot see clearly, the doctor can tell that the examinee cannot see clearly, the doctor inputs the result into the computer through the keyboard in real time for storage, and the stored result corresponds to the position where the E word mark appears.

In this way, after the E-shaped mark with the random opening direction of the second visual target appears at all positions of the grid point once, because the foveal region of the macula lutea is the most vision-sensitive region, although the foveal power of the macula lutea may be inhibited to some extent due to strabismus and the like of the examinee, the foveal region of the macula lutea still is likely to be a region with good vision around the abnormal retina imaging point corresponding to the abnormal sight line. By displaying the second sighting target within the range of the radius visual angle of 1-10 degrees around the first sighting target, if a region with the best vision relative to other regions exists, the connecting line of the display position of the second sighting target and the pupil center at the moment can be judged to be a central foveal vision of the macula lutea, the second sighting target is imaged at the central foveal vision of the macula lutea, the connecting line of the center of the pupil of the left eye and the display position of the second sighting target at the moment is a second sight line, and the non-central watching deviation angle is the included angle of the first sight line and the second sight line. For example, in this embodiment, after the display of all grid points is finished, if the examinee is most clearly seen with the second sighting target "E" displayed at the position of the viewing angle of 5 ° right from the first sighting target, the opening direction of the "E" can be clearly seen, and the opening direction of the "E" cannot be clearly seen at any other position, it is determined that the non-central gaze deviation angle of the left eye is 5 °, the direction is the temporal side (relative position outside the eyeball) of the macular fovea line of the abnormal visual line, and the abnormal retinal imaging point is at the position of the viewing angle of 5 ° on the nasal side of the macular fovea on the retina.

Meanwhile, the eye movement point calculation module monitors the eye movement point of the left eye of the tested person in real time, if the eye movement point of the left eye leaves the position displayed by the first sighting mark, the position of the first sighting mark is moved in real time to be equal to the position of the eye movement point of the left eye, and the display position of the second sighting mark is moved to keep the relative position (difference value of relative visual angle) of the second sighting mark and the first sighting mark unchanged; or setting the test result invalid during the period that the eye movement point of the left eye leaves the first sighting mark position, and carrying out the test again.

EXAMPLE III

Some subjects, such as young children, cannot accurately visualize whether the expression clearly shows the sighting target. Thus, visual evoked potentials can be used to objectively record the degree of visual acuity in different locations of a subject's retina.

For example, one subject, whose left eye is known to be a non-central fixation, is of the type "stable non-central fixation".

A visual detection device comprises a display module, an image shooting and processing module, an eye movement point calculating module, a visual evoked potential calculating module and a non-central gazing deviation angle calculating module. The system also comprises an electronic computer, and an image processing algorithm of the image shooting and processing module, an eye movement point calculating module and a non-central gazing deviation angle calculating module are programs running on the electronic computer. In addition, the apparatus comprises a head fixture on which the chin of the subject is placed, the distance between the head fixture and the display module being fixed and known.

The image shooting and processing module and the eye movement point calculating module have the same equipment composition, working principle and embodiment.

The visual evoked potential calculating module is used for giving flash or pattern graphic stimulation to eyes, and recording Visual Evoked Potentials (VEPs) in the occipital cortex area through skin electrodes placed at corresponding positions of the scalp.

The specific working mode of the non-central gaze deviation angle detection module is as follows:

firstly, the image shooting and processing module and the eye movement point calculating module carry out monocular calibration on the left eye, and calculate the eye movement point of the left eye in real time according to the shot image. And then the display module displays the sighting target, the examinee needs to watch the sighting target, in the embodiment, the sighting target is a plus character mark, and the line connecting the center of the pupil of the B eye and the sighting target is a first sight line. The periodic blinking dots are displayed at variable positions around the optotype within a 1 ° radius to 10 ° radius viewing angle. The positions where the flickering light spots appear are within a radius view angle of 1-10 degrees around the visual target, on grid points which are spaced by 1 degree in the longitudinal direction and the transverse direction, each position is sequentially displayed from left to right from top to bottom, and each position is repeatedly flicked for multiple times, so that VEP waveforms are superposed to improve the signal-to-noise ratio. The visual evoked potential calculating module records the visual evoked potential and corresponds to the display position of the flickering light spot.

In this way, after the scintillation light spot appears at all positions, because the fovea region of the macula lutea is the most vision-sensitive region, although the fovea vision of the macula lutea of the examinee may be inhibited to some extent due to strabismus and the like, the fovea region of the macula lutea still is likely to be the most sensitive region around the abnormal retina imaging point corresponding to the abnormal sight line to the visual evoked potential induced by the scintillation light spot. By displaying the flickering light spot within the range of the radius visual angle of 1-10 degrees around the visual target, if an area with relatively obvious and highest visual evoked potential amplitude exists, the connecting line of the position of the flickering light spot and the pupil center at the moment can be judged to be a central foveal vision line of the macula, the flickering light spot is imaged at the central foveal position of the macula, the connecting line of the pupil center of the left eye and the display position of the flickering light spot at the moment is a second sight line, and the non-central watching deviation angle is an included angle between the first sight line and the second sight line.

Meanwhile, the eye movement point calculation module monitors the eye movement point of the left eye of the tested person in real time, if the eye movement point of the left eye leaves the position displayed by the visual target, the position of the visual target is moved in real time to be equal to the position of the eye movement point of the left eye, and the display position of the flickering light spot is moved to keep the display position of the flickering light spot and the relative position (difference value of relative visual angle) of the visual target unchanged; or setting the test result invalid when the eye moving point of the left eye leaves the visual target position, and carrying out the test again.

Example four

The visual training device disclosed in this embodiment can perform visual training on stable non-central gaze.

For example, a non-central fixation patient whose left eye is known to be a non-central fixation, which is known to be a stable non-central fixation and whose non-central fixation deviation angle is known, has a fixed relative position of the abnormal retinal image point of the left eye and the fovea maculae.

A vision training device comprises a display module, an image shooting and processing module, an eye movement point calculating module, a yellow spot central fovea visual line intersection point calculating module and a training module.

In this embodiment, the display module is a display, and the displayed content can be seen by only the left eye and cannot be seen by the right eye. The right eye can be shielded by an eye mask, or the right eye can be shielded by a polarized display, a naked-eye 3D display and the like mentioned in the first embodiment.

The equipment composition and the working principle and the embodiment of the image shooting and processing module are the same.

The equipment composition and the working principle of the eye movement point calculation module are the same as those of the embodiment. The left eye movement point coordinate is the intersection point of the left eye abnormal sight line and the display plane.

The equipment also comprises an electronic computer, and an image processing algorithm of the image shooting and processing module, an eye movement point calculating module, a macular central foveal vision intersection point calculating module and a training module are programs operated on the computer. The relative position and distance of the patient's eye from the display is also known. According to the relative position and distance between the left eye and the display and the coordinates of the eye movement point of the left eye, the abnormal sight of the left eye can be obtained; according to the abnormal sight of the left eye and the non-central watching deviation angle of the left eye, the foveal sight of the left eye macula lutea can be calculated, and the intersection point of the foveal sight of the left eye macula lutea and the display plane is calculated, which is called the intersection point of the foveal sight of the left eye macula lutea for short.

In the present embodiment, as shown in fig. 7, it is known that the left-eye non-central gaze deviation angle is 3 °, and the left-eye abnormal line of sight is on the temporal side of the macular foveal line (relative position outside the eyeball). The distance between the center of the pupil of the left eye and the display plane of the display is known to be 60 cm. When the left eye looks ahead, the intersection position of the abnormal sight line of the left eye and the display plane is W, and the abnormal sight line of the left eye is rotated clockwise by 3 degrees (clockwise direction from top to bottom), so that the abnormal sight line of the left eye is the foveal macular center sight line of the left eye. As can be seen from fig. 7, the intersection C of the left-eye macular foveal line and the display plane is directly to the right of W, and it can be calculated that 60cm × tan3 ° ≈ 3.1cm, so that the left-eye macular foveal line intersection C is directly to the right of 3.1cm from the intersection W of the left-eye abnormal line and the display plane.

The training module is a program running on a computer. During visual training, a clear image is displayed at the intersection of the foveal line of the macula, and no image or a suppressed image is displayed at the position of the eye movement point of the left eye (the intersection of the abnormal line of sight of the left eye and the display plane). The image may be suppressed by one or more of blurring, reducing display resolution, dimming brightness, and reducing contrast, and the image obtained after the suppression is a suppressed image.

One training mode that the training module can use is that during visual training, clear images are displayed at the intersection of the left eye macular central concave sight line, and when the intersection of the left eye macular central concave sight line moves, the image display position moves along with the intersection; no image is displayed elsewhere on the display plane. During visual training, the image display range does not exceed the circular range of the visual angle with the center of the left eye macular fovea line intersection point as the circle center and the radius of less than or equal to 2 degrees. For example, the image may be a number, a character, a letter, a small visual target, a small animation, a flashing light spot, etc. In this embodiment, the image is an arabic number that changes every 2 seconds on the display plane at a viewing angle of 1 °, and is displayed at the intersection of the foveal vision line of the left eye and the display plane, requiring the patient's left eye to view the arabic number with a single eye and verbally report to the doctor what number was seen. No image is displayed elsewhere on the display plane. Through visual training, the fovea maculae position of the left eye of the patient can be always stimulated by the image, and the abnormal retina imaging point position of the left eye cannot be stimulated by the image, so that the patient can gradually recover to normal fovea maculae fixation.

The training module can also use a training mode that, during visual training, the display module displays clear images near the intersection point of the left eye macular foveal vision line, displays depressed images in a far area of the intersection point of the left eye macular foveal vision line, and the image display position does not move along with the movement of the intersection point of the left eye macular foveal vision line. When the image is displayed on the display module, the range of displaying the clear image is not more than the circular range of the viewing angle with the intersection point of the central concave viewing line of the yellow spot of the left eye as the circle center and the radius less than or equal to 2 degrees. For example, in this embodiment, an image is displayed on the display, the image is a complete Chinese text, the image display position does not move with the movement of the foveal line of the left eye macula, but the image is displayed clearly in a range that the C point of the foveal line of the left eye macula is the center of a circle and the viewing angle of 1 ° in radius, and other regions are blurred images. Therefore, when a patient reads the text with the left eye by a single eye, only the text image near the intersection position of the foveal line of the left eye macula lutea can be seen clearly, and the blurred text image corresponds to the imaging point position of the abnormal retina of the left eye. Through visual training, the vision training is helpful for the patient to enhance the capability of foveal fixation and gradually restore normal foveal fixation.

EXAMPLE five

The device composition and the working principle of the display module, the image shooting and processing module, the eye movement point calculating module and the macular foveal vision intersection point calculating module are the same as those of the fourth embodiment. Wherein the content displayed by the display module is visible only to the left eye and not to the right eye. In addition, the apparatus comprises a head fixture on which the chin of the subject is placed, the distance between the head fixture and the display module being fixed and known. The training module in this embodiment is a program running on a computer. In the visual training, first, an image P is displayed at an intersection W of the left-eye abnormal visual line and the display plane₁Displaying an image P at an intersection C of the foveal vision line of the left eye macula and the display plane₂Picture P₁And image P₂The display range does not exceed the circular range of the visual angle with the radius less than or equal to 2 degrees. Gradually increasing the image P under the condition of keeping the position of the eye movement point of the left eye constant (i.e. the eye is not moved, and the positions of W and C are not changed)₁And (5) the degree of depression, and performing visual training. The image suppression mode can be one or more of blurring, reducing display resolution, dimming brightness, reducing contrast and the like.

For example, a blinking blue light spot is displayed at the position of the intersection W of the abnormal visual line of the left eye and the display plane, and a blinking red light spot is displayed at the position of the intersection C of the foveal visual line of the left eye and the display plane, directly in front of the left eye of the patient, the red light spot and the blue light spot being the same in size and the blinking frequency. Let the patient look at the blue spot.

First, the brightness of the blue spot is the same as the brightness of the red spot, both being L₀. When the patient fixates on the blue spot with an abnormal line of sight to the left eye, the blue spot is imaged on an abnormal retinal image spot while the red spot is imaged on the fovea of the macula. Because the patient's left eye is under non-centric fixation and foveal vision is inhibited, the sensitivity of the fovea may be less than that of the abnormal retinal image spot, and the patient may subjectively perceive the red spot as less bright than the blue spot.

Then, the brightness of the blue spot is gradually decreased, and the brightness of the red spot remains unchanged. When the brightness of the blue light spot is reduced to a certain degree, the patient can subjectively feel that the brightness of the red light spot is the same as that of the blue light spot, and record that the brightness of the blue light spot is L at the time₁。

Next, the brightness of the blue spot is gradually reduced further, and the brightness of the red spot remains unchanged. The patient is made to perceive the blue spot as having a significantly weaker intensity than the red spot, and if the intensity of the blue spot is further reduced below the threshold value L₂In time, the patient may inadvertently look at the red spot with an abnormal line of sight because the blue spot is obscured. Keeping the brightness of the blue spot equal to L₂Or slightly larger than L₂And is less than L₁So that the fovea of the macula of a patient can be always strongly stimulated, and meanwhile, abnormal retina imaging points corresponding to abnormal sight linesThe site is stimulated as weakly as possible. Through such visual training, the patient is helped to enhance the foveal fixation ability and gradually restore normal foveal fixation.

As vision training continues over a period of time, L increases with increasing foveal fixation₂/L₀The ratio of (a) to (b) is gradually reduced, and even when the foveal fixation ability is restored to near normal vision level, the left eye of the patient can maintain fixation of the red spot with the foveal vision even if the brightness of the blue spot is reduced to 0.

EXAMPLE six

The disclosed vision training equipment of this embodiment can be watched non-central the carrying on vision training, not only is applicable to stable form non-central gazing, still is applicable to the type of wandering off non-central gazing.

For example, a non-central fixation patient whose left eye is known to be a wandering non-central fixation, the relative positions of the abnormal retinal image point and the fovea maculae of the left eye are not fixed. The right eye is the central fixation eye and the Kappa angle of the right eye is known. The measurement method of the Kappa angle of the right eye may be the measurement method in the first embodiment, or may be another Kappa angle measurement method.

A vision training device comprises a display module, an image shooting and processing module, a macular fovea visual line intersection point calculating module and a training module. The system also comprises an electronic computer, and the algorithm of the image shooting and processing module, the macular fovea vision line calculation module and the training module are all programs running on the electronic computer. In addition, the equipment also comprises a head fixing device, the chin of the examinee is placed on the head fixing device, the height of the left eye and the height of the right eye are the same, the distance between the left eye and the right eye and the display is the same, and the distance between the head fixing device and the display module is fixed and known.

In this embodiment, the display module is a display.

The image shooting and processing module comprises 2 near-infrared cameras and 2 near-infrared light sources and can continuously shoot images of the left eye; the image processing module comprises an image processing function, can perform image processing calculation on the shot image of the area to obtain a three-dimensional coordinate of the center of the pupil of the left eye and a three-dimensional coordinate of the center of each corneal reflection point of the left eye, and the relative positions of the image shooting and processing module and the display module are known.

The macula lutea fovea visual line intersection point calculating module can calculate the intersection point of the left eye macula lutea fovea visual line and the display plane in real time. The principle is that the left eye pupil midline can be calculated in real time by using the measurement mode in the first embodiment. According to the principle of physiological symmetry of the left eye and the right eye, the included angle beta between the central foveal vision of the macula of the left eye and the pupil midline of the left eye is equal to the Kappa angle alpha of the right eye, and the included angle directions are in mirror symmetry with the median sagittal plane of a human body. Therefore, the foveal vision of the left eye macula lutea can be calculated in real time according to the pupil midline of the left eye and the included angle β. And because the relative positions of the image shooting and processing module and the display module are known, the device can calculate the intersection point of the foveal vision of the left eye macula lutea and the display plane of the display module in real time, and the position of the intersection point is set as C.

When the training module is used for visual training, a clear image is displayed near the intersection point of the foveal vision line of the macula lutea of the left eye, and no image or a suppressed image is displayed in other areas. Through the vision training, the fovea maculata can be always stimulated by clear images, and the patient can be helped to gradually recover the normal fovea maculata fixation.

For example, during visual training, a clear image is displayed at the intersection of the foveal vision line of the macula lutea of the left eye, and the image display range does not exceed the circular range of the visual angle with the intersection of the foveal vision line of the macula lutea of the left eye as the center of a circle and the radius less than or equal to 2 degrees. When the intersection point of the foveal vision of the center of the macula lutea moves, the position displayed by the image moves along with the intersection point; no image is displayed elsewhere on the display plane. The images may be numbers, characters, letters, small visuals, small animations, flashing light spots, etc. In this embodiment, the image is a Chinese character that changes every 2 seconds on the display plane, the viewing angle is 1 °, and the displayed position is the intersection of the foveal vision of the left eye macula lutea and the display plane, requiring the patient to view the Chinese character with a single eye in the left eye and verbally report to the doctor what Chinese character was seen. No image is displayed elsewhere on the display plane.

For example, during visual training, the display module displays a clear image near the intersection point of the foveal vision line of the macula lutea of the left eye, and the range of displaying the clear image does not exceed the circular range of the viewing angle with the intersection point of the foveal vision line of the macula lutea of the left eye as the center of a circle and the radius less than or equal to 2 degrees. The area outside this range displays a suppressed image, and the image may be suppressed by one or more of blurring, reduction in display resolution, dimming in brightness, reduction in contrast, and the like. The position of the image display does not move with the movement of the left eye macula lutea foveal line intersection. In this embodiment, the image displayed on the display is a complete Chinese text, the image display position does not move with the movement of the eye sight, but the image is clearly displayed in a range where the center C of the foveal vision line of the left eye is the center of a circle and the radius of the foveal vision line is 1 ° of the viewing angle, and other areas are blurred images. Therefore, when a patient reads the text with the left eye by a single eye, only the text image near the intersection position of the foveal line of the left eye macula lutea can be seen clearly, and the blurred text image corresponds to the imaging point position of the abnormal retina of the left eye.

EXAMPLE seven

According to the visual training device disclosed by the embodiment, the vision training is performed on non-central fixation by utilizing the simultaneous vision function or the fusion vision function and the stereoscopic vision function of binocular vision.

For one patient, the right eye is the central fixation eye, the left eye is the non-central fixation eye, the left eye is the stable non-central fixation and the non-central fixation deviation angle is known, and the relative positions of the abnormal retina imaging point of the left eye and the fovea maculae are fixed.

A vision training device comprises a display module, an image shooting and processing module, an eye movement point calculating module, a yellow spot central fovea visual line intersection point calculating module and a training module. The system also comprises an electronic computer, and the algorithm of the image shooting and processing module, the macular fovea vision line calculation module and the training module are all programs running on the electronic computer. In addition, the apparatus comprises a head fixture on which the chin of the subject is placed, the distance between the head fixture and the display module being fixed and known.

The display module in this embodiment is a polarized display, and the patient wears polarized glasses, and the polarized display can display an image that is visible only for the left eye and can display an image that is visible only for the right eye. The polarized glasses worn by the patient can transmit near infrared light of 850 nm.

The image shooting and processing module in the embodiment includes 1 near-infrared camera and 2 LED near-infrared light sources with the light emitting wavelength of 850nm, and the components and the working principle of the image shooting and processing module are similar to those of the eye movement point calculating module in the second embodiment, but the eye movement point calculating module in the embodiment can shoot images of left eyes and right eyes. In the eye movement point calculation module in this embodiment, first, monocular calibration is performed on the right eye and the left eye respectively; when the single eye of the right eye is calibrated, only the right eye can see the calibration sighting mark displayed by the display module, a calibration function of the right eye is obtained through the single eye calibration of the right eye, after the calibration of the right eye is finished, the coordinate of a moving point of the right eye is calculated according to the image of the right eye and the calibration function of the right eye, and the coordinate of the moving point of the right eye is the intersection point of the central concave sight line of the yellow spot of the right eye and the display plane; when the left eye is calibrated in a single eye mode, only the left eye can see the calibration sighting mark displayed by the display module, the calibration function of the left eye is obtained through the calibration in the single eye mode of the left eye, after the calibration of the left eye is finished, the left eye movement point coordinate is calculated according to the left eye image and the left eye calibration function, and the left eye movement point coordinate is the intersection point of the abnormal sight line of the left eye and the display plane. The monocular calibration method and the method of calculating the eye movement point are similar to the related method in the second embodiment. In another embodiment, the image capturing and processing module may also be a device including two near-infrared cameras and two near-infrared light sources, so that the left eye and the right eye can obtain their respective calibration functions by single-point calibration of a single eye, and then the eye movement point coordinates of the left eye and the right eye are calculated by the eye movement point calculating module.

The working principle of the macular foveal vision intersection point calculation module is as follows: because the relative position and distance between the left eye and the display are known, the abnormal sight line of the left eye is a straight line passing through the central position of the pupil of the left eye and the moving point of the eye of the left eye, and the central foveal vision line of the macula lutea of the left eye can be calculated according to the abnormal sight line of the left eye and the non-central watching deviation angle; the intersection point of the foveal vision of the left eye macula lutea is the intersection point of the foveal vision of the left eye macula lutea and the display plane.

A training module, during visual training, the display module firstly displays the image P only visible for the right eye_A(ii) a Let the trainer look at the image P_AThen, an image P visible only to the left eye is displayed at the intersection of the foveal vision line of the left eye macula and the display module_B(ii) a Then image P_AAnd image P_BAnd keeping the simultaneous display and performing visual training. In this embodiment, the image P_AAnd image P_BThe display range is not more than the circular range of the visual angle with the radius less than or equal to 2 degrees.

In the visual training, the image P_AAnd image P_BMay be complementary images, the patient may attempt to complement the image seen by the left eye and the image seen by the right eye into a complete image in the brain, which may simultaneously train the patient's simultaneous vision functions. For example, image P_AIs a birdcage, only the right eye can see the birdcage; image P_BIs a bird that is visible only to the left eye. Then the doctor asks the patient whether the bird and the birdcage can be seen at the same time, if so, the patient can see the bird and the birdcage at the same time; if the patient can only see the bird or the birdcage, the patient does not have simultaneous vision and further training is needed.

In the visual training, the image P_AAnd image P_BCan be images with the same shape, size and the like, and the patient can try to fuse the image seen by the left eye and the image seen by the right eye into a single image in the brain, so that the fused visual function of the patient can be trained simultaneously. For example, image P_AIs a bird, only the right eye can see; image P_BIs a similar bird and is visible only to the left eye. Then the doctor asks the patient to see a plurality of birds, if one bird is seen, the patient is indicated to have a fusion view; if two birds are seen, the patient does not have a fusion view yet and further training is required.

In the visual training, the image P_AAnd image P_BOr a stereo image with binocular parallax, and the patient can see the image seen by the left eye and the image seen by the right eyeThe images attempt to create stereo vision in the brain, which simultaneously trains the patient's stereoscopic functions. For example, image P_AAnd image P_BCan be combined into a three-dimensional image of a small ball and can roll back and forth circularly. Then the doctor asks the patient whether the patient can see a small ball rolling back and forth, the current distance is far or near, and if the patient can correctly identify the small ball and judge the distance, the condition shows that the patient has stereoscopic vision; if the patient can not correctly recognize the small balls and judge the distance, the patient does not have stereoscopic vision and needs further training.

Image P when the intersection of the foveal vision lines of the left eye macula changes_BCan move along with the position of the central foveal vision line intersection of the left eye macula lutea, so that the image P is always positioned at the intersection point of the central foveal vision lines of the left eye macula lutea_BImaging is performed on the foveal position of the left eye macula.

Example eight

A non-central fixation patient is known to have its left eye as a non-central fixation, its right eye as a central fixation, and the Kappa angle of the right eye is known. The measurement method of the Kappa angle of the right eye may be the measurement method in the first embodiment, or may be another Kappa angle measurement method.

A vision training device comprises an image shooting and processing module, a macular fovea vision calculation module and a liquid crystal shielding module.

The image shooting and processing module comprises 2 near-infrared cameras and 2 near-infrared light sources and can continuously shoot images of the left eye; the image processing function is included, and the image processing calculation can be carried out on the shot image of the area to obtain the three-dimensional coordinates of the center of the pupil of the left eye and the center of each corneal reflection point of the left eye.

The foveal macular line calculation module may calculate the intersection of the foveal macular line of the left eye and the display plane in real time. The principle is that the left eye pupil midline can be calculated in real time by using the measurement mode in the first embodiment. According to the principle of physiological symmetry of the left eye and the right eye, the included angle beta between the central foveal vision of the macula of the left eye and the pupil midline of the left eye is equal to the Kappa angle alpha of the right eye, and the included angle directions are in mirror symmetry with the median sagittal plane of a human body. Therefore, the foveal vision of the left eye macula can be calculated in real time according to the left eye pupil midline and the included angle beta.

The liquid crystal shelters from the liquid crystal lens that the module is located left eye field of vision scope, and the liquid crystal shelters from the module and can control the liquid crystal lens near the crossing point department near the concave sight in yellow spot center of left eye and liquid crystal lens transparent, and other regions are opaque, carry out the vision training, and the position in transparent region can change in real time according to the change of the concave sight in patient's left eye yellow spot center, is located the crossing point department of the concave sight in left eye yellow spot center and liquid crystal lens all the time. The relative positions of the liquid crystal shielding module and the image shooting and processing module are fixed and known. The method for controlling any area of the liquid crystal lens to be transparent or opaque can be a program running on an electronic computer or can be controlled by a miniaturized embedded system such as an FPGA (field programmable gate array). The transparent range of the liquid crystal shielding module is not more than the circular range of the visual angle with the intersection point of the central concave line of the yellow spot as the circle center and the radius of less than or equal to 2 degrees. In the present embodiment, a circular range having a radius equal to a viewing angle of 1 ° is set. In this way, the field of vision can be seen by the left eye of the patient, only the foveal region of the macula of the left eye of the patient can be imaged, continuous imaging stimulation is performed on the foveal region of the macula of the left eye of the patient, and meanwhile, the abnormal retina imaging points corresponding to the abnormal sight line of the left eye cannot be stimulated by external images, so that the foveal fixation of the macula can be recovered by the patient.

When performing the visual training, the content of the visual training may be images, videos, animations and the like on the display. The present device may also be integrated into wearable head-mounted apparatuses, such as head-mounted glasses, VR devices, AR devices, and the like. For example, when the present apparatus is integrated with a pair of head-mounted eyeglasses, a patient can wear such eyeglasses for a long time and perform visual training in daily life or learning.

Claims

1. A visual inspection apparatus, which is characterized in that one of the two eyes is a central fixation eye, called A eye, and the other eye is a non-central fixation eye, called B eye, comprising:

a display module;

the central fixation eye Kappa angle calculation module defines the central foveal vision of the yellow spots of the A eyes as a straight line passing through the central fovea of the yellow spots of the A eyes and the center of pupils of the A eyes, and the central foveal vision of the yellow spots of the A eyes is intersected with the fixation position of the A eyes when the A eyes fix foreign objects; the central fixation eye Kappa angle calculation module controls the display module to display the sighting target T which can be seen by only A eyes at the specified position_aThe examinee gazes at the optotype T_aThen, the central foveal line of the macula of the A eye passes through the center of the pupil of the A eye and the visual target T_aA straight line of (a); the central fixation eye Kappa angle calculation module calculates the three-dimensional coordinates of the pupil center of the eye A and the three-dimensional coordinates of the centers of the corneal reflection points of the eye A to obtain the pupil center line of the eye A, and further calculates to obtain the Kappa angle of the eye A, wherein the Kappa angle of the eye A is the included angle between the central foveal vision line of the yellow spots of the eye A and the pupil center line of the eye A;

the non-center gaze deviation angle calculation module defines the abnormal sight of the B eye as a straight line passing through the center of the pupil of the B eye and the gaze position when the B eye gazes at a foreign object; defining the foveal vision of the macula lutea of the B eye as a straight line passing through the fovea macula of the B eye and the center of the pupil of the B eye; the non-central gazing deviation angle calculation module controls the display module to display the sighting target T which can be seen by only B eyes at the designated position_bThe examinee gazes at the optotype T_bThen, the abnormal visual line of the B eye passes through the center of the pupil of the B eye and the visual target T_bA straight line of (a); the non-center gaze deviation angle calculation module calculates the three-dimensional coordinates of the center of the pupil of the eye B and the three-dimensional coordinates of the centers of all cornea reflection points of the eye B to obtain the center of the pupil of the eye BThe line and the macular fovea centralis sight of the B eye, and further calculating to obtain a non-central gaze deviation angle of the B eye, wherein the non-central gaze deviation angle of the B eye is an included angle between the abnormal sight of the B eye and the macular fovea centralis sight of the B eye, and the method comprises the following steps of:

2. The visual inspection device of claim 1, further comprising a determination module configured to calculate an angle between a foveal vision line of a macula of a B eye and an abnormal vision line of the B eye when the B eye is monocular-focused on the eye; and when the included angle between the central concave vision of the macula lutea of the B eye and the abnormal vision of the B eye is a stable value within a period of time, the judgment module judges that the B eye is stably and non-centrally watched.

3. The visual inspection device of claim 1, further comprising a determination module configured to calculate an angle between a foveal vision line of a macula of a B eye and an abnormal vision line of the B eye when the B eye is monocular-focused on the eye; and when the included angle between the central concave sight of the macula lutea of the B eye and the abnormal sight of the B eye is an unstable value within a period of time, the judgment module judges that the B eye is wandering non-central gazing.

4. A visual inspection device for determining whether one of the eyes is a non-central fixation eye, referred to as the B eye, which is known to be a stable non-central fixation, comprising:

the eye movement point calculation module is used for obtaining a calibration function of the B eye through single-eye calibration of the B eye, and further calculating to obtain a B eye movement point coordinate according to the B eye image and the B eye calibration function, wherein when the single-eye calibration is carried out on the B eye, the eye movement point calculation module controls the display module to display a calibration visual target which can be seen by only the B eye; a non-central gaze deviation angle calculation module:

5. A visual inspection device for determining whether one of the eyes is a non-central fixation eye, referred to as the B eye, which is known to be a stable non-central fixation, comprising:

a non-central gaze deviation angle calculation module:

6. A vision training device, wherein one of the two eyes is a non-central fixation eye, referred to as the B eye, which is known to be stable non-central fixation and has a known non-central fixation deviation angle, comprising:

7. The vision training device of claim 6, wherein the training module controls the display module to display a clear image near the intersection of the foveal vision line of the macula lutea of the B eye during vision training, and when the intersection of the foveal vision line of the macula lutea of the B eye moves, the position of the image display moves along with the movement; and displaying no image at other positions of the display plane of the display module.

8. The vision training device of claim 7, wherein the training module displays the image in a range not exceeding a circular range with a radius of 2 ° or less from the center of the center-foveal line intersection of the macula lutea of the B eye during vision training.

9. The vision training device according to claim 6, wherein in the training module, during the vision training, the display module displays a clear image near the intersection of the foveal lines of the macula of the B eye, displays a depressed image in a region farther away from the intersection of the foveal lines of the macula of the B eye, and the image display position does not move with the movement of the intersection of the foveal lines of the macula of the B eye.

10. The vision training device of claim 9, wherein in the training module, when the training module controls the display module to display the image, the range of displaying the clear image does not exceed a circular range with the center of the center concave sight intersection of the macula lutea of the B eye as the center and the radius of the view angle being less than or equal to 2 degrees.

11. A vision training device, wherein one of the two eyes is a non-central fixation eye, referred to as the B eye, which is known to be stable non-central fixation and has a known non-central fixation deviation angle, comprising:

12. The vision training apparatus of claim 11, wherein in the training module, image P₁And image P₂The display range is not more than the circular range of the visual angle with the radius less than or equal to 2 degrees.

13. A vision training apparatus, one of the eyes being a central fixation eye, referred to as the a-eye, for which the Kappa angle is known, and the other eye being a non-central fixation eye, referred to as the B-eye, comprising:

14. The vision training device of claim 13, wherein the training module displays an image at the foveal vision intersection of the B-eye macula during vision training, and when the foveal vision intersection of the B-eye macula moves, the position of the image display moves along with the movement; no image is displayed elsewhere on the display plane.

15. The vision training device of claim 14, wherein the training module displays the image in a range not exceeding a circular range with a radius of 2 ° or less from the center of the foveal line intersection of the macula lutea of the B eye during the vision training.

16. The vision training device of claim 13, wherein in the training module, during the vision training, the display module displays a clear image near the intersection of the foveal lines of the macula of the B-eye, and displays a depressed image in a region far away from the intersection of the foveal lines of the macula of the B-eye, and the image display position does not move with the movement of the intersection of the foveal lines of the macula of the B-eye.

17. The vision training apparatus of claim 16, wherein the training module displays the image on the display module in a range not exceeding a circular range having a viewing angle of 2 ° or less with a radius of a center of a foveal line intersection of macula lutea of B-eye as a center.

18. A vision training device for providing a centered fixation eye, referred to as the a eye, in one of two eyes and a non-centered fixation eye, referred to as the B eye, in the other eye, known as a stabilized non-centered fixation and known non-centered fixation deviation angle, comprising:

19. The vision training apparatus of claim 18, wherein the training module is configured to perform the vision training with image P_AAnd image P_BAre complementary images that need to be viewed simultaneously to form a complete image.

20. The vision training apparatus of claim 18, wherein the training module is configured to perform the vision training with image P_AAnd image P_BAre images of the same shape and size.

21. The vision training apparatus of claim 18, wherein the training module is configured to perform the vision training with image P_AAnd image P_BThe stereoscopic image has binocular parallax.

22. A visual training apparatus according to claims 18-21, characterised in that in the training module, an image P_AAnd image P_BThe display range is not more than the circular range of the visual angle with the radius less than or equal to 2 degrees.

23. According to the rightA vision training apparatus as claimed in claims 18 to 22, characterized in that the image P is adapted to be displayed when the intersection of the foveal vision line of the macula of the B-eye changes_BThe position of the eye B is moved along with the eye B, and is always positioned at the intersection point of the foveal vision of the macula lutea of the eye B.

24. A vision training apparatus, one of the eyes being a central fixation eye, referred to as the a-eye, for which the Kappa angle is known, and the other eye being a non-central fixation eye, referred to as the B-eye, comprising:

25. The vision training device of claim 24, wherein the transparent range of the liquid crystal shielding module does not exceed the circular range of the viewing angle with the radius less than or equal to 2 degrees and with the center of the intersection point of the foveal vision of the macula lutea of the B eye as the center.

26. The vision training apparatus of claim 24, wherein the vision training apparatus is integrated into a head-mounted device, the head-mounted device being a pair of head-mounted glasses, a VR device, or an AR device.