Eye tracking device and method based on line array camera position coordinate detection

Abstract

The application discloses an eye movement tracking device and method based on line array camera position coordinate detection, and proposes the scheme in view of the problems such as complex operation of a plane array in the prior art. One set of detection system is arranged on each side of a mirror frame, one side is used for horizontal detection, and the other side is used for vertical detection. One line array camera coordinate after eye rotation is detected to detect the rotation of one direction of eye movement, and the horizontal rotation angle of the eye and the vertical rotation angle of the eye are detected by using the principle of eye co-observation. The advantage lies in that the horizontal and vertical detection is innovatively proposed, and the detection can be completed by simple calculation on one mirror frame. In combination with a micro motor, initialization correction is completed for different users, and the applicability is higher.

Description

Technical Field

[0001] This invention relates to eye-tracking technology, and more particularly to an eye-tracking device and method based on the position coordinate detection of a linear array camera. Background Technology

[0002] Most existing eye-tracking detection solutions use externally connected cameras to capture images of the eye's state, and then use algorithms to calculate the eye-tracking path. This generates a large amount of redundant data, putting pressure on computing power, storage, and low latency. In addition, the use of large-area array image sensors makes integration difficult.

[0003] Existing infrared camera eye-tracking detection devices are all based on area array image sensors, which have several drawbacks: For example, they are affected by ambient light; the image of the eye captured by the camera is affected by ambient light, and dim lighting or strong light sources shining on the eye can affect the camera's image quality. The detection distance is limited; the camera usually needs to be placed relatively close to effectively detect eye movements, which may affect the user's natural behavior. Placement requirements are high; to ensure accuracy, the camera needs to be placed in a stable and appropriate position, which may require a special bracket to fix the camera, increasing the difficulty and cost of installation. Eye occlusion issues also exist; if the user wears glasses, sunglasses, etc., it may obstruct part of the eye, affecting the accuracy of eye-tracking detection. Furthermore, some detection schemes rely too heavily on backend computing, with fixed detection device positions and no simple and feasible hardware adjustment solutions. For example, traditional eye trackers typically require high-resolution cameras and dedicated image processing algorithms to collect and analyze eye movement data. These algorithms need to be calculated on the backend data acquisition system, requiring specialized hardware and software support.

[0004] Eye-tracking detection is mainly classified into two types: off-axis and on-axis reflection tracking, as follows: Figure 1 and Figure 2 As shown, the core principles of both methods are the same: a laser beam and a photodiode are fixed together to form a measurement device called a "photodiode-laser beam system." This system is then placed near the subject's eye, allowing the laser beam to be guided through a MEMS mirror to ensure the reflected light always hits the corneal surface. When the laser beam hits the corneal surface, reflection occurs. This reflection point is captured by the photodiode and processed by computer software. By tracking the movement of the reflection point, the computer can determine the position and movement of the eyeball, including rotation and tilt. The aforementioned planar array image sensor is composed of multiple photodiodes arranged in a two-dimensional array on a plane. Summary of the Invention

[0005] The purpose of this invention is to provide an eye-tracking device and method based on the position coordinate detection of a linear array camera, so as to solve the problems existing in the prior art.

[0006] The eye-tracking device based on the position coordinate detection of a linear array camera described in this invention includes a frame, a right temple hinged to the right side of the frame, and a left temple hinged to the left side of the frame.

[0007] The right temple near the frame is equipped with a first digital micromirror, a first micro electric actuator, and a first linear array camera. The extension end of the first micro electric actuator is equipped with a first laser.

[0008] The left temple is equipped with a second digital micromirror, a second micro electric actuator, and a second linear array camera near the frame. The extension end of the second micro electric actuator is equipped with a second laser.

[0009] The delay directions of the first linear array camera and the second linear array camera are orthogonal;

[0010] The first linear array camera is used to detect the result of the laser emitted by the second laser being reflected sequentially by the right cornea and the first digital micromirror;

[0011] The second linear array camera is used to detect the result of the laser emitted by the first laser being reflected sequentially by the cornea of ​​the left eye and the second digital micromirror;

[0012] It also integrates a micro drive processing circuit board; the micro drive processing circuit board is electrically connected to the first digital micromirror, the first micro electric actuator, the first laser, the first linear array camera, the second digital micromirror, the second micro electric actuator, the second laser, and the second linear array camera, respectively, and is used to calculate eye movement information based on the detection results of the first linear array camera and the second linear array camera.

[0013] The first linear array camera extends horizontally and is used to detect horizontal variables of eye movement information; the second linear array camera extends vertically and is used to detect vertical variables of eye movement information.

[0014] Both the first laser and the second laser are VCSEL light sources, or both are infrared LEDs.

[0015] The eye-tracking method based on the position coordinate detection of a linear array camera described in this invention utilizes the eye-tracking device for eye tracking.

[0016] Before eye tracking, the human eye's emmetropia state is corrected: the micro drive processing circuit board drives the first micro electric push rod and / or the second micro electric push rod, so that the laser emitted by the second laser is reflected sequentially by the right cornea and the first digital micromirror and then aligned with the center position of the first linear array camera, and the laser emitted by the first laser is reflected sequentially by the left cornea and the second digital micromirror and then aligned with the center position of the second linear array camera.

[0017] The eye-tracking device and method based on linear array camera position coordinate detection described in this invention have the advantages of innovatively proposing separate detection for horizontal and vertical directions, which can be completed with simple calculations on a single frame. Combined with a micro-motor, initial calibration can be performed for different users, resulting in greater applicability. It solves problems such as eye-tracking detection being affected by ambient light, detection interfering with user's natural behavior, and eye occlusion, and features miniaturization, integration, simple path, and reduced backend computational burden. Attached Figure Description

[0018] Figure 1 This is a schematic diagram illustrating the principle of off-axis eye-tracking methods in existing technologies.

[0019] Figure 2 This is a schematic diagram illustrating the principle of existing eye-tracking methods that align on the central axis.

[0020] Figure 3 This is a schematic diagram of the eye-tracking device described in this invention.

[0021] Figure 4 This is a schematic diagram of the eye-tracking device described in this invention from another angle.

[0022] Figure 5 This is a schematic diagram illustrating the principle of the eye-tracking method described in this invention.

[0023] Figure label:

[0024] 10. Frame, 11. Right temple, 12. Left temple, 13. Visual zone;

[0025] 21 First digital micromirror, 22 First micro-electric actuator, 23 First laser, 24 First linear array camera; 31 Second digital micromirror, 32 Second micro-electric actuator, 33 Second laser, 34 Second linear array camera. Detailed Implementation

[0026] like Figure 3 and Figure 4 As shown, the eye-tracking device based on the position coordinate detection of a linear array camera described in this invention includes a frame 10, a right temple 11 hinged to the right side of the frame 10, and a left temple 12 hinged to the left side of the frame 10.

[0027] The right temple 11 is equipped with a first digital micromirror 21, a first micro electric actuator 22 and a first linear array camera 24 near the frame 10. The extension end of the first micro electric actuator 22 is equipped with a first laser 23.

[0028] The left temple 12 is equipped with a second digital micromirror 31, a second micro electric actuator 32 and a second linear array camera 34 near the frame 10. The extension end of the second micro electric actuator 32 is equipped with a second laser 33.

[0029] The delay directions of the first linear array camera 24 and the second linear array camera 34 are orthogonal.

[0030] The first linear array camera 24 is used to detect the result of the laser emitted by the second laser 33 being reflected sequentially by the right cornea and the first digital micromirror 21.

[0031] The second linear array camera 34 is used to detect the result of the laser emitted by the first laser 23 being reflected sequentially by the cornea of ​​the left eye and the second digital micromirror 31.

[0032] It also integrates a micro-drive processing circuit board. The micro-drive processing circuit board is electrically connected to the first digital micromirror 21, the first micro-electric actuator 22, the first laser 23, the first linear array camera 24, the second digital micromirror 31, the second micro-electric actuator 32, the second laser 33, and the second linear array camera 34, respectively, and is used to calculate eye movement information based on the detection results of the first linear array camera 24 and the second linear array camera 34.

[0033] The first linear array camera 24 extends horizontally and is used to detect horizontal variables of eye movement information. The second linear array camera 34 extends vertically and is used to detect vertical variables of eye movement information.

[0034] Both the first laser 23 and the second laser 33 are VCSEL light sources or infrared LEDs.

[0035] Before eye tracking, the human eye's emmetropia state is corrected: the micro drive processing circuit board drives the first micro electric push rod 22 and / or the second micro electric push rod 32, so that the laser emitted by the second laser 33 is reflected sequentially by the right cornea and the first digital micromirror 21 and then aligned with the center position of the first linear array camera 24, and so that the laser emitted by the first laser 23 is reflected sequentially by the left cornea and the second digital micromirror 31 and then aligned with the center position of the second linear array camera 34.

[0036] The working principle of the eye-tracking device based on linear array camera position coordinate detection described in this invention, and the corresponding eye-tracking method are as follows: Figure 5As shown, when the human eye focuses on an object, the left and right eyeballs rotate at approximately the same angle. A detection system is placed on each side of the frame 10, one side for horizontal detection and the other for vertical detection. The eye movement in one direction is detected by detecting the coordinates of a linear array camera after the eyeball rotates. Utilizing the principle of co-vision, the horizontal and vertical rotation angles of the eyeball are detected separately. Detecting coordinates in two directions significantly reduces the complexity of backend computation. Different eye movement angles correspond to different coordinate positions of the two linear array cameras. The detected coordinate positions and data are uploaded to a host computer or the micro-drive processing circuit board for simple processing, such as function fitting between coordinate values ​​and eye movement angle values, to convert them into eye movement angle information, thereby achieving eye movement tracking and detection.

[0037] For those skilled in the art, various other corresponding changes and modifications can be made based on the technical solutions and concepts described above, and all such changes and modifications should fall within the protection scope of the claims of this invention.

Claims

1. An eye-tracking device based on the position coordinate detection of a linear array camera, comprising a frame (10), a right temple (11) hinged to the right side of the frame (10), and a left temple (12) hinged to the left side of the frame (10). Its features are, The right temple (11) near the frame (10) is equipped with a first digital micromirror (21), a first micro electric push rod (22) and a first line array camera (24), and the extension end of the first micro electric push rod (22) is equipped with a first laser (23). The left temple (12) is equipped with a second digital micromirror (31), a second micro electric push rod (32) and a second linear array camera (34) near the frame (10). The extension end of the second micro electric push rod (32) is equipped with a second laser (33). The delay directions of the first linear array camera (24) and the second linear array camera (34) are orthogonal; The first linear array camera (24) is used to detect the result of the laser emitted by the second laser (33) being reflected sequentially by the right cornea and the first digital micromirror (21); The second linear array camera (34) is used to detect the result of the laser emitted by the first laser (23) being reflected sequentially by the cornea of ​​the left eye and the second digital micromirror (31); It also integrates a micro drive processing circuit board; the micro drive processing circuit board is electrically connected to the first digital micromirror (21), the first micro electric push rod (22), the first laser (23), the first linear array camera (24), the second digital micromirror (31), the second micro electric push rod (32), the second laser (33) and the second linear array camera (34), respectively, and is used to calculate eye movement information based on the detection results of the first linear array camera (24) and the second linear array camera (34); The first linear array camera (24) extends horizontally and is used to detect horizontal variables of eye movement information; the second linear array camera (34) extends vertically and is used to detect vertical variables of eye movement information. Before eye tracking, the human eye's normal gaze state is corrected: the micro drive processing circuit board drives the first micro electric push rod (22) and the second micro electric push rod (32) so that the laser emitted by the second laser (33) is reflected by the right cornea and the first digital micromirror (21) and then aligned with the center of the first linear array camera (24), and the laser emitted by the first laser (23) is reflected by the left cornea and the second digital micromirror (31) and then aligned with the center of the second linear array camera (34).

2. The eye-tracking device based on linear array camera position coordinate detection according to claim 1, characterized in that, The first laser (23) and the second laser (33) are both VCSEL light sources or both infrared LEDs.

3. An eye-tracking method based on linear array camera position coordinate detection, characterized in that, Eye tracking is performed using the eye tracking device as described in any one of claims 1-2.

4. The eye-tracking method based on linear array camera position coordinate detection according to claim 3, characterized in that, Before eye tracking, the human eye's normal gaze state is corrected: the micro drive processing circuit board drives the first micro electric push rod (22) and the second micro electric push rod (32) so that the laser emitted by the second laser (33) is reflected by the right cornea and the first digital micromirror (21) and then aligned with the center of the first linear array camera (24), and the laser emitted by the first laser (23) is reflected by the left cornea and the second digital micromirror (31) and then aligned with the center of the second linear array camera (34).

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