An optical simulation method for an eye-tracking system

Abstract

This invention relates to the field of eye-tracking technology, specifically to an optical simulation method for an eye-tracking system. The method includes: selecting a camera and infrared illumination lamp according to system requirements; establishing a camera optical system and infrared LED illumination model based on the selection results; performing an initial layout of the camera and infrared illumination lamp optical arrangement according to system requirements; performing tracking simulations on the camera imaging optical path and the infrared illumination lamp illumination optical path respectively; determining whether the geometric optical indicators meet the requirements under the current optical layout; and determining whether the irradiance indicators meet the requirements under the current optical layout. This invention, through the judgment and iteration of geometric optical and irradiance indicators, gradually brings the system closer to the required system indicators and gradually stabilizes, thereby optimizing the recognition accuracy of the eye-tracking system, improving the system's operating range, and ensuring that the infrared radiation generated in the system meets the safety requirements for human eye infrared irradiance.

Description

Technical Field

[0001] This invention relates to the field of eye-tracking technology, and more specifically to an optical simulation method for an eye-tracking system. Background Technology

[0002] Traditional human-computer interaction (HCI) media typically include external devices such as mice, keyboards, and touchscreens that achieve HCI functionality by acquiring information from the user's hand movements. While these devices have ergonomic design principles, their disadvantages become apparent in certain task scenarios. These include situations where the user needs to move within a space, when the operator needs to multitask and has a high cognitive load, or when the operator has a physical disability and cannot freely use these traditional HCI devices. The emergence of eye-tracking technology provides a more natural, intuitive, and efficient interaction method to the HCI process.

[0003] The eyes are vital organs for humans to acquire information from the surrounding world; humans obtain 80% of their information through their eyes. Eye-tracking technology captures and identifies the gaze points of the human eye, transforming eye movements into a natural human-computer interface, providing users with more diverse hybrid human-computer interaction modes.

[0004] Currently, eye-tracking solutions that have been put into engineering applications include those based on Video of the Eye (VOG), Electrooculography (EOG), and Pupil-Corneal Reflection (PCCR). Among these, PCCR has gained more attention due to its high accuracy, small error, and interference-free characteristics, and has resulted in various product forms, currently used in AR / VR glasses, desktop monitoring, and other products. PCCR is based on the characteristics of the cornea as a protruding structure of the eyeball with a smooth and reflective surface. During eye-tracking measurements, an image of the eye after infrared illumination is captured, and the pupil features and the light spot features on the corneal surface are extracted. The vector direction of the line connecting the current pupil center and the corneal reflection point is calculated, thereby deducing the visual axis direction of the eye in space. Combined with the image information captured by the scene camera, the position of the eye's gaze point is obtained. However, since the accuracy of this system depends on the quality of the eye images captured by the eye camera, optimizing the selection and layout of the eye camera and infrared illuminator through optical design is particularly important. Summary of the Invention

[0005] To address the aforementioned technical problems, this invention provides an optical simulation method for an eye-tracking system. Addressing the eye image requirements of eye-tracking systems based on the pupil-corneal reflection method, this method effectively optimizes the image quality of eye images captured by the eye camera through iterative spatial layout, and also assesses the infrared radiation safety of the human eye under this layout.

[0006] The first objective of this invention is to provide an optical simulation method for an eye-tracking system, comprising: Select the camera and infrared fill light according to system requirements; Based on the selection results, optical models of relevant components of the eye-tracking system are established. These optical models include an optical system model of the eye camera lens, an infrared illumination model, and an optical model of the human eye structure. Based on system requirements, a preliminary layout of the camera and infrared fill light lamps was planned. Tracking simulations were performed on the camera imaging optical path and the infrared fill light illumination optical path, respectively. Determine whether the geometric optical indicators meet the requirements under the current optical layout. The geometric optical indicators include the imaging quality of the eye camera, the corneal spot distribution of the infrared fill light lamp, and the range of eye movement that can be tracked by eye tracking. Determine whether the irradiance index meets the requirements under the current optical layout, wherein the irradiance index is the infrared irradiance of the human corneal surface; If the geometric optical parameters or the irradiance parameters do not meet the requirements, the camera and infrared fill light optical layout should be readjusted until both the geometric optical parameters and the irradiance parameters meet the requirements.

[0007] In one embodiment, the structural optical model of the human eye is the Le Grand eyeball model.

[0008] In one embodiment, the Le Grand eye model has a human eye interpupillary distance of 54-74 mm, and the rotation center of the human eye model is located 11.5 mm behind the limbus plane and is relatively offset to the nasal side by 1.6 mm.

[0009] In one embodiment, the tracking simulation simulates the process of light reflecting off the human eye and entering the camera lens to form an image; the tracking simulation of the infrared fill light lamp illumination path simulates the process of light emitted by the infrared fill light lamp reaching the cornea of ​​the human eye to form a corneal reflection spot.

[0010] In one embodiment, the imaging quality of the eye camera refers to the process of establishing an optical system model of the eye camera, calculating the imaging quality of the camera through the optical system in optical design software according to the layout and the human eye at a specific distance from the object surface, and determining whether the modulation transfer function and the speckle meet the system requirements.

[0011] In one embodiment, the infrared fill light corneal spot distribution refers to the position of the spot formed by the light emitted by the LED after being reflected from the corneal surface and entering the eye camera lens for final imaging.

[0012] In one embodiment, the eye movement range that can be tracked by eye tracking refers to the maximum range of eye rotation angles in the eye image that meets the algorithm requirements.

[0013] In one embodiment, the infrared irradiance of the human corneal surface refers to the infrared irradiance of the human corneal surface under infrared illumination.

[0014] A second objective of this invention is to provide a system for an optical simulation method of an eye-tracking system, comprising: The model building module is used to select cameras and infrared fill lights according to system requirements; based on the selection results, optical models of relevant components of the eye tracking system are established, including an optical system model of the eye camera lens, an infrared fill light illumination model, and an optical model of the human eye structure. The simulation module is used to perform initial layout of the camera and infrared illumination lamp optical arrangement according to system requirements; to perform tracking simulation of the camera imaging optical path and the infrared illumination lamp lighting optical path respectively; to determine whether the geometric optical indicators meet the requirements under the current optical layout, the geometric optical indicators including the imaging quality of the eye camera, the corneal spot distribution of the infrared illumination lamp, and the eye movement range that can be tracked by eye tracking; and to determine whether the irradiance indicators meet the requirements under the current optical layout, the irradiance indicators being the infrared irradiance of the human corneal surface. The layout optimization module is used to readjust the optical layout of the camera and infrared fill light if the geometric optical index or the irradiance index does not meet the requirements, until both the geometric optical index and the irradiance index meet the requirements.

[0015] The present invention has at least the following beneficial effects: This invention provides an optical simulation method for an eye-tracking system. Based on the special requirements of the pupil-corneal reflection method for eye-tracking systems, this method improves the quality of eye images captured by the eye camera by iteratively arranging the spatial layout of optical components, providing a clear and usable image foundation for subsequent eye-tracking algorithms. After determining the optical layout, the method simultaneously evaluates whether the infrared radiation received by the human eye under this layout meets safety standards, thus avoiding damage to the human eye from infrared light.

[0016] The optical design and simulation method of the eye-tracking system of this invention, through judgment and iteration of geometric optical indicators and irradiance indicators, enables the system to gradually approach the system requirements and gradually stabilize. This optimizes the recognition accuracy of the eye-tracking system, improves the system's working range, and ensures that the infrared radiation generated in the system meets the infrared irradiance safety requirements of the human eye. Attached Figure Description

[0017] Figure 1This is a flowchart illustrating the optical design and simulation method of an eye-tracking system according to the present invention. Figure 2 This invention is based on the Le Grand eye model, which is an optical model of the human eye structure. Figure 3 This is a schematic diagram of eye-tracking optical tracing in this invention; Figure 4 This is the result of modulation transfer function calculation in lens image quality evaluation according to a certain embodiment of the present invention; Figure 5 This is the result of the blur spot calculation in the lens image quality evaluation of a certain embodiment of the present invention; Figure 6 This is a real photograph and schematic diagram of an eye image according to a certain embodiment of the present invention; Figure 7 This is a schematic diagram of the effective and ineffective distribution of light spots in an eye image according to a certain embodiment of the present invention; Figure 8 This is the irradiance simulation evaluation result of a certain embodiment of the present invention. Detailed Implementation

[0018] In order to illustrate the technical means and effects adopted by the present invention to achieve the intended purpose, the following detailed description is provided in conjunction with the embodiments.

[0019] The purpose of this invention is to provide an optical simulation method for an eye-tracking system, which mainly revolves around "meeting the requirements of eye images based on the pupil-corneal reflection method" and aims to "optimize image quality and assess infrared radiation safety". It is promoted through a closed-loop logic of "selection-modeling-layout-simulation-dual index judgment", which can be specifically broken down into a four-layer logical framework of "core objective → prerequisite constraints → core process → key detail supplement".

[0020] This invention addresses the specific requirements of eye images in eye-tracking systems based on the pupil-corneal reflection method. By iteratively arranging the spatial layout of optical components, it improves the quality of eye images captured by the eye camera (providing a clear and usable image foundation for subsequent eye-tracking algorithms). After determining the optical layout, it simultaneously evaluates whether the infrared radiation received by the human eye under this layout meets safety standards, thus avoiding damage to the human eye from infrared light.

[0021] To achieve the above objectives, see Figure 1 As shown, an optical simulation method for an eye-tracking system includes: S1. Select cameras and infrared fill lights according to system requirements; The main purpose of the selection is to determine the infrared irradiance of the human corneal surface, which refers to the infrared irradiance of the human corneal surface under infrared illumination.

[0022] S2. Based on the selection results, establish optical models of the relevant components of the eye tracking system. The optical models of the relevant components of the eye tracking system include the optical system model of the eye camera lens, the infrared fill light illumination model, and the optical model of the human eye structure. The optical model of the human eye structure used is the Le Grand eyeball model.

[0023] In the Le Grand eye model, the interpupillary distance of the human eye ranges from 54 to 74 mm. The rotation center of the human eye model is located 11.5 mm vertically behind the limbus plane and is relatively offset towards the nasal side by 1.6 mm.

[0024] Establishing optical models of relevant components of the eye-tracking system involves transforming physical hardware into "simulable digital models," covering three key components: an optical system model of the eye camera lens (simulating the optical path of camera imaging); an infrared illumination model (simulating the emission and propagation path of infrared light); and an optical model of the human eye structure (based on the Le Grand model, simulating the reflection and refraction characteristics of light by the human eye).

[0025] S3. Based on system requirements, perform preliminary layout of camera and infrared fill light optical arrangement; The purpose of the initial layout is to determine the initial spatial position of the components (such as the distance between the camera and the human eye, and the angle of the infrared fill light relative to the camera) to provide an "initial layout scheme" for subsequent simulations.

[0026] S4. Perform tracking simulations on the camera imaging optical path and the infrared fill light illumination optical path respectively. The simulation of the camera imaging optical path is to simulate the process of light reflecting off the human eye and entering the camera lens to form an image; the simulation of the simulation of the infrared fill light illumination optical path is to simulate the process of light emitted by the infrared fill light reaching the cornea of ​​the human eye to form a corneal reflection spot.

[0027] During the tracking simulation, optical simulation tools are used to simulate the "actual propagation process of light". Imaging light path tracking: simulates the process of light reflecting from the human eye (pupil, cornea) and entering the camera lens to finally form an image; illumination light path tracking: simulates the process of light emitted by infrared fill light reaching the human eye cornea and forming corneal reflective spots.

[0028] S5. Determine whether the geometric optical indicators meet the requirements under the current optical layout. The geometric optical indicators include the imaging quality of the eye camera, the corneal spot distribution of the infrared fill light lamp, and the range of eye movement that can be tracked by eye tracking. The aforementioned image quality of the eye camera refers to the process of establishing an optical system model of the eye camera, calculating the image quality on the camera through the optical system in optical design software according to the layout and the human eye at a specific distance from the object surface, and determining whether the modulation transfer function and the speckle meet the system requirements.

[0029] The aforementioned infrared fill light corneal spot distribution refers to the location of the spot formed when the light emitted by the LED is reflected from the corneal surface and enters the eye camera lens for final imaging.

[0030] The eye movement range that can be tracked by eye tracking refers to the maximum range of eye rotation angles in the eye image that meets the algorithm requirements.

[0031] Determine if the geometric and optical indicators under the current layout meet the requirements and verify the system's "functionality": Evaluate the core geometric and optical indicators through simulation results to determine if the image quality and tracking range meet the standards. Specifically, this includes: the imaging quality of the eye camera (such as resolution, distortion rate, and contrast, which directly affect the accuracy of eye movement feature extraction); the distribution of the infrared supplementary light spot on the cornea (whether the spot size, shape, and position are clear and stable, which is key to pupil-corneal reflection localization); and the range of eye movement that can be tracked by eye tracking (covering the daily rotation angles of the human eye to ensure no blind spots in tracking). If not satisfied, return to S3 to adjust the layout and re-simulate; if satisfied, proceed to the next step. S6. Determine whether the irradiance index meets the requirements under the current optical layout. The irradiance index is the infrared irradiance of the corneal surface of the human eye. The infrared irradiance of the human cornea refers to the infrared irradiance of the human cornea under infrared illumination.

[0032] If the geometric optical parameters in S5 or the irradiance parameters in S6 do not meet the requirements, return to S3 to readjust the optical layout of the camera and infrared fill light until both the geometric optical parameters and the irradiance parameters meet the requirements.

[0033] Determine whether the irradiance index under the current layout meets the requirements and verify the system's "safety": only assess the "infrared irradiance intensity on the surface of the human cornea" (the amount of irradiance directly or reflected from the infrared supplementary light to the human eye) and determine whether it is within the safety threshold; if it does not meet the requirements, return to S3 to adjust the layout (such as increasing the distance between the supplementary light and the human eye, adjusting the angle), and re-simulate; if it meets the requirements, determine that the current layout is a feasible solution.

[0034] The entire process of this invention is not a "one-time pass," but rather an iterative process involving dual judgments in "S5 + S6": If the geometric optics indicators do not meet the standards (such as blurred imaging or spot shift): there is no need to proceed to the safety assessment. Instead, return to "Step 3 (Adjust Layout)" and re-perform optical path tracing and indicator judgment. If the geometric optical indicators meet the standards but the irradiation safety does not (e.g., the image is qualified but the infrared irradiation is excessive): it is still necessary to return to "S3 (adjust layout)" and reduce the irradiation by changing the position / angle of the fill light, etc., and then re-verify the two indicators; The design and simulation of the current optical layout are only completed when both the geometric optical index and the radiometric index meet the requirements, ensuring that the system is both "easy to use" and "safe".

[0035] To further illustrate the optical simulation method for an eye-tracking system provided by this invention, it is described in conjunction with the accompanying drawings.

[0036] Taking a glasses-type eye-tracking system configuration as an example, an optical design and simulation method for an eye-tracking system is presented, such as... Figure 1 As shown, the steps are as follows: S1: Camera and infrared supplementary light selection. Based on the camera's imaging distance, field of view, camera size, and other specifications in the initial configuration of the system, a preliminary camera selection is completed.

[0037] S2: Establishment of optical models for eye-tracking system components. This involves establishing optical models for relevant components of the eye-tracking system, including an optical system model of the eye camera lens, an infrared illumination model, and an optical model of the human eye structure. The camera lens optical system model can be created based on the parameters of the selected lens. The infrared illumination model is created based on the parameters of the selected infrared illumination lamp. Figure 2 As shown, the optical model of the human eye structure was created using the Le Grand eyeball model. The interpupillary distance of the human eye ranges from 54 to 74 mm. The rotation center of the human eye model is located 11.5 mm behind the limbus plane and is relatively offset to the nasal side by 1.6 mm.

[0038] In this embodiment, the optical system of the eye camera can be designed in reverse equivalent way based on the focal length, field of view, image size, total lens length and other data of the selected camera, and then replaced in situ during the simulation process.

[0039] The optical system of the eye camera can be designed in reverse equivalent way based on the data such as the emission angle, angular radiation characteristics, radiant flux, emission spectrum, and emission surface size of the selected infrared fill light, and then replaced in situ during the simulation process.

[0040] S3: Initial layout of the camera and infrared fill light optical arrangement. (For example...) Figure 3As shown, based on the structure 1 mounted on the system, the relative positional relationship between the human eye model 2 and the structure 1 is determined, and the initial layout of the eye camera 3, infrared fill light 4 and scene camera 5 is completed on the structure 1.

[0041] In this embodiment, the infrared supplementary lights are arranged symmetrically around the optical axis of the eyeball. This provides uniform illumination to the eye area and ensures that the light spot 22 reflected by the cornea 21 is evenly distributed around the pupil 23, which helps improve the recognition accuracy of the reflected light spot by the eye-tracking algorithm.

[0042] S4: Optical ray tracing simulation. The above model is placed into optical simulation software, and the Monte Carlo ray tracing algorithm is used to simulate the interaction between the ray and the eye tracking system components, the human eye model, and the frame structure to obtain the ray tracing results.

[0043] S5: Determine whether the geometric optical parameters meet the requirements. The determination of the geometric optical parameters includes: the imaging quality of the eye camera, the corneal light spot distribution of the infrared supplementary lamp, and the range of eye movement that can be tracked by eye tracking. If the above parameters are not met, return to step S3 to optimize the layout design based on the results.

[0044] In this embodiment, the imaging quality of the eye camera refers to the imaging quality on the camera after passing through the optical system, calculated in optical design software based on the layout and the human eye's position on an object at a specific distance, by establishing an optical system model of the eye camera and determining the modulation transfer function (e.g., ...). Figure 4 (as shown) and diffuse spots (such as) Figure 5 (As shown) Does it meet the system requirements?

[0045] The aforementioned infrared fill light corneal spot distribution refers to the location of the spot formed when light emitted by the LED is reflected from the corneal surface and enters the eye camera lens to form an image. For example... Figure 6 As shown, this is an image of a human eye captured by a human eye camera at a certain moment. The image can capture the relative position of the light spot 31 formed by the infrared supplement lamp on the cornea 32 of the human eye. If the light spot falls on the pupil 33 and the sclera 34, a light spot image with clear edges cannot be captured.

[0046] The eye movement range that can be tracked by eye tracking refers to the maximum range of eye rotation angles in the eye image that meets the algorithm's requirements. For example... Figure 7 As shown, the distribution of infrared supplementary light spot on the cornea in the eye image is used to determine whether the algorithm's requirement for identifying the light spot coordinates is met. Furthermore, by traversing the various angles of the human eye model's rotation around the eyeball's rotation center, boundary detection is performed on the range of human eye rotation angles under this round of optimized optical layout to determine whether the system requirements are met.

[0047] S6: Determine whether the irradiance indicators meet the requirements. The determination of the irradiance indicators includes the infrared irradiance of the human cornea surface. If the above indicators are determined to be unsatisfactory, return to step S3 to optimize the layout design based on the result.

[0048] In this embodiment, the infrared irradiance of the human cornea surface refers to the infrared irradiance of the human cornea surface under infrared supplemental lighting. According to the photobiological safety standard for lamps and lamp systems (GB / T 20145-2006) and the threshold requirements for infrared radiation hazards to the eyes (GB / T41265-2022), light sources with an irradiance time > 1000s should have an irradiance of < 100W / m² on the human eye. 2 To determine whether the infrared irradiance of the infrared supplementary light on the surface of the human cornea meets the requirements. Based on... Figure 8 As shown, infrared light can be uniformly irradiated onto the corneal surface, with a maximum local irradiance of 51.0 W / m². 2 The average irradiance is 33.9 W / m². 2 It meets the safety requirements for infrared radiation to the human eye.

[0049] In summary, this invention provides an optical design and simulation method for an eye-tracking system, comprising: selecting a camera and infrared illumination lamp according to system requirements; establishing a camera optical system and infrared LED illumination model based on the selection results; performing an initial layout of the camera and infrared illumination lamp optical arrangement according to system requirements; performing tracking simulations on the camera imaging optical path and the infrared illumination lamp illumination optical path respectively; determining whether the geometric optical indicators meet the requirements under the current optical layout; and determining whether the irradiance indicators meet the requirements under the current optical layout. This invention's optical design and simulation method for the eye-tracking system, through the judgment and iteration of geometric optical indicators and irradiance indicators, gradually brings the system closer to the required system indicators and gradually stabilizes. This optimizes the recognition accuracy of the eye-tracking system, improves the system's operating range, and ensures that the infrared radiation generated in the system meets the safety requirements for human eye infrared irradiance.

[0050] This invention provides a system for an optical simulation method of an eye-tracking system, comprising: The model building module is used to select cameras and infrared fill lights according to system requirements; based on the selection results, optical models of relevant components of the eye tracking system are established, including an optical system model of the eye camera lens, an infrared fill light illumination model, and an optical model of the human eye structure. The simulation module is used to perform initial layout of the camera and infrared illumination lamp optical arrangement according to system requirements; to perform tracking simulation of the camera imaging optical path and the infrared illumination lamp lighting optical path respectively; to determine whether the geometric optical indicators meet the requirements under the current optical layout, the geometric optical indicators including the imaging quality of the eye camera, the corneal spot distribution of the infrared illumination lamp, and the eye movement range that can be tracked by eye tracking; and to determine whether the irradiance indicators meet the requirements under the current optical layout, the irradiance indicators being the infrared irradiance of the human corneal surface. The layout optimization module is used to readjust the optical layout of the camera and infrared fill light if the geometric optical index or the irradiance index does not meet the requirements, until both the geometric optical index and the irradiance index meet the requirements.

[0051] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the principles of the present invention should be included within the protection scope of the present invention.

Claims

1. An optical simulation method for an eye-tracking system, characterized in that, include: Select the camera and infrared fill light according to system requirements; Based on the selection results, optical models of relevant components of the eye-tracking system are established. These optical models include an optical system model of the eye camera lens, an infrared illumination model, and an optical model of the human eye structure. Based on system requirements, a preliminary layout of the camera and infrared fill light lamps was planned. Tracking simulations were performed on the camera imaging optical path and the infrared fill light illumination optical path, respectively. Determine whether the geometric optical indicators meet the requirements under the current optical layout. The geometric optical indicators include the imaging quality of the eye camera, the corneal spot distribution of the infrared fill light lamp, and the range of eye movement that can be tracked by eye tracking. Determine whether the irradiance index meets the requirements under the current optical layout, wherein the irradiance index is the infrared irradiance of the human corneal surface; If the geometric optical parameters or the irradiance parameters do not meet the requirements, the camera and infrared fill light optical layout should be readjusted until both the geometric optical parameters and the irradiance parameters meet the requirements.

2. The optical simulation method for the eye-tracking system according to claim 1, characterized in that, The optical model of the human eye structure used is the Le Grand eyeball model.

3. The optical simulation method for the eye-tracking system according to claim 2, characterized in that, In the Le Grand eye model, the interpupillary distance of the human eye ranges from 54 to 74 mm. The rotation center of the human eye model is located 11.5 mm behind the limbus plane and is relatively offset to the nasal side by 1.6 mm.

4. The optical simulation method for the eye-tracking system according to claim 1, characterized in that, The tracking simulation simulates the process of light reflecting off the human eye and entering the camera lens to form an image. The tracking simulation of the illumination path of an infrared supplementary light lamp simulates the process by which the light emitted by the infrared supplementary light lamp reaches the cornea of ​​the human eye and forms a corneal reflection spot.

5. The optical simulation method for the eye-tracking system according to claim 1, characterized in that, The aforementioned image quality of the eye camera refers to the process of establishing an optical system model of the eye camera, calculating the image quality on the camera through the optical system in optical design software according to the layout and the human eye at a specific distance from the object surface, and determining whether the modulation transfer function and the speckle meet the system requirements.

6. The optical simulation method for the eye-tracking system according to claim 1, characterized in that, The aforementioned infrared fill light corneal spot distribution refers to the location of the spot formed when the light emitted by the LED is reflected from the corneal surface and enters the eye camera lens for final imaging.

7. The optical simulation method for the eye-tracking system according to claim 1, characterized in that, The eye movement range that can be tracked by eye tracking refers to the maximum range of eye rotation angles in the eye image that meets the algorithm requirements.

8. The optical simulation method for the eye-tracking system according to claim 1, characterized in that, The infrared irradiance of the human cornea refers to the infrared irradiance of the human cornea under infrared illumination.

9. A system for an optical simulation method of the eye-tracking system according to claim 1, characterized in that, include: The model building module is used to select cameras and infrared fill lights according to system requirements; Based on the selection results, optical models of relevant components of the eye-tracking system are established. These optical models include an optical system model of the eye camera lens, an infrared illumination model, and an optical model of the human eye structure. The simulation module is used to perform an initial layout of the camera and infrared fill light lamps according to system requirements; The camera imaging optical path and the infrared illumination optical path are simulated separately for tracking; it is determined whether the geometric optical indicators meet the requirements under the current optical layout. The geometric optical indicators include the imaging quality of the eye camera, the corneal spot distribution of the infrared illumination lamp, and the range of eye movement that can be tracked by eye tracking; it is also determined whether the irradiance indicators meet the requirements under the current optical layout. The irradiance indicators are the infrared irradiance of the human corneal surface. The layout optimization module is used to readjust the optical layout of the camera and infrared fill light if the geometric optical index or the irradiance index does not meet the requirements, until both the geometric optical index and the irradiance index meet the requirements.

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