Eye movement tracking device and near-eye display equipment

Abstract

The invention relates to the field of eye movement tracking, and provides an eye movement tracking device and near-to-eye display device.The eye movement tracking device comprises a lens assembly, the lens assembly comprises a lens body layer and a holographic medium layer, and the holographic medium layer is arranged on the lens body layer; interference information of a light beam of an illumination light source for eye movement tracking is recorded in the holographic medium layer; the light source assembly is used for providing a reproduction light beam for the holographic dielectric layer; wherein the illumination light source light beam and the reproduction light beam have coherence, and the holographic dielectric layer is used for reproducing the illumination light source light beam used for eye movement tracking when irradiated by the reproduction light beam of the light source assembly. Eye movement tracking is carried out through the illumination light source beams reproduced by the holographic medium layer instead of light beams emitted by lamp beads, and the lamp beads are prevented from being arranged on the lens, so that the lamp beads are prevented from blocking the sight of a user, and the visual area of the lens is increased.

Description

Technical Field

[0001] The present application relates to the field of eye tracking, and in particular to an eye tracking device and a near-eye display device. Background Art

[0002] Current smart glasses usually use the Purkinje spots formed by the light beam shining on the eyeball as a reference point to calculate the position of the human eye's gaze point. Therefore, it is necessary to set lamp beads at a position relative to the human eye to emit a light beam to illuminate the human eye, thereby forming a Purkinje spot on the human eye. However, setting lamp beads at a position relative to the human eye, such as setting lamp beads on the lenses of smart glasses, will inevitably block the user's line of sight. In addition, a sufficient number of lamp beads are often required to achieve high-precision eye tracking functions. How to reduce the occlusion of the human eye by the eye tracking hardware of smart glasses to improve the user experience of smart glasses has become an urgent problem to be solved. Summary of the invention

[0003] The main purpose of this application is to provide an eye tracking device and a near-eye display device, aiming to increase the visible area of ​​the lens.

[0004] In a first aspect, the present application provides an eye tracking device, the eye tracking device comprising:

[0005] A lens assembly, the lens assembly comprising a lens body layer and a holographic medium layer, the holographic medium layer being arranged on the lens body layer, and the holographic medium layer recording interference information of an illumination light source beam for eye tracking;

[0006] A light source assembly, the light source assembly is used to provide a reproduction light beam for the holographic medium layer;

[0007] The illumination light source beam and the reproduction light beam are coherent, and the holographic medium layer is used to reproduce the illumination light source beam for eye tracking when irradiated by the reproduction light beam of the light source assembly.

[0008] In some embodiments, the lens body layer includes an optical waveguide layer, and a coupling region is disposed on the optical waveguide layer. The coupling region is used to couple the reproduced light beam into the optical waveguide layer for transmission, so that the reproduced light beam irradiates the holographic medium layer.

[0009] In some embodiments, the eye tracking device further comprises:

[0010] A camera assembly is used to capture a target image formed by the illumination light source beam in a human eye, so as to perform eye tracking according to the target image based on a preset eye tracking algorithm.

[0011] In some embodiments, the illumination light source beam includes a first divergence angle beam and a second divergence angle beam, and the camera assembly is used to capture a Purkinje spot target image formed by the first divergence angle beam in a human eye, so as to perform eye tracking according to the Purkinje spot in the target image based on a preset eye tracking algorithm;

[0012] Alternatively, the camera assembly is used to capture the interference fringe image formed by the second divergence angle light beam in the human eye, so as to perform eye tracking according to the interference fringes in the target image based on a preset eye tracking algorithm;

[0013] The first divergence angle of the first divergence angle light beam is smaller than the second divergence angle of the second divergence angle light beam.

[0014] In some embodiments, when the reproduced light beam of the light source assembly is irradiated onto the holographic medium layer, the holographic medium layer can reproduce a first exit angle light beam and a second exit angle light beam for eye tracking.

[0015] In some embodiments, the light source assembly is used to provide a first reproduction light beam and / or a second reproduction light beam to the holographic medium layer;

[0016] When the first reproduced light beam of the light source assembly is irradiated onto the holographic medium layer, the holographic medium layer can reproduce a first exit angle light beam for eye tracking; and / or

[0017] When the second reproduced light beam of the light source assembly irradiates the holographic medium layer, the holographic medium layer can reproduce a second exit angle light beam for eye tracking.

[0018] In some embodiments, the light source assembly includes a reconstruction light source and a dichroic mirror, and the dichroic mirror is used to change the angle of the reconstruction light beam of the reconstruction light source to obtain the first reconstruction light beam and the second reconstruction light beam.

[0019] In some embodiments, the illumination light source beam and the reproduction light beam are infrared beams.

[0020] In a second aspect, the present application also provides a near-eye display device, which includes the eye tracking device described in any one of the embodiments of the present application.

[0021] In some embodiments, the near-eye display device further comprises a visible light source for providing a virtual image for the near-eye display device.

[0022] The present application provides an eye tracking device and a near-eye display device, the eye tracking device comprising: a lens assembly, the lens assembly comprising a lens body layer and a holographic medium layer, the holographic medium layer being arranged on the lens body layer, the holographic medium layer recording interference information of an illumination light source beam for eye tracking; a light source assembly, the light source assembly being used to provide a reproduced light beam for the holographic medium layer; wherein the illumination light source beam and the reproduced light beam are coherent, the holographic medium layer being used to reproduce the illumination light source beam for eye tracking when irradiated by the reproduced light beam of the light source assembly. Eye tracking is performed by using the light beam reproduced by the holographic medium layer, replacing the light beam emitted by the lamp beads for eye tracking, avoiding the need to set lamp beads on the lens, thereby avoiding the lamp beads from blocking the user's line of sight and increasing the visible area of ​​the lens. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0024] Figure 1 A schematic block diagram of the structure of an eye tracking device provided in one embodiment of the present application;

[0025] Figure 2 A schematic block diagram of the structure of an eye tracking device provided in another embodiment of the present application;

[0026] Figure 3 A schematic block diagram of the structure of an eye tracking device provided in another embodiment of the present application;

[0027] Figure 4 A schematic diagram of a first divergent angle light beam provided in an embodiment of the present application;

[0028] Figure 5 A schematic diagram of a target image illuminated by a first divergent angle light beam provided in an embodiment of the present application;

[0029] Figure 6 A schematic diagram of a second divergent angle light beam provided in an embodiment of the present application;

[0030] Figure 7 A schematic diagram of a target image illuminated by a second divergent angle light beam provided in an embodiment of the present application;

[0031] Figure 8 A schematic diagram of a light beam with a first exit angle provided by an embodiment of the present application;

[0032] Fig. 9 A schematic diagram of a light beam with a second exit angle provided in one embodiment of the present application.

[0033] Fig.10 A schematic block diagram of a usage scenario of a lens preparation method provided in another embodiment of the present application. DETAILED DESCRIPTION

[0034] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0035] The flowcharts shown in the accompanying drawings are only examples and do not necessarily include all the contents and operations / steps, nor must they be executed in the order described. For example, some operations / steps may be decomposed, combined or partially merged, so the actual execution order may change according to actual conditions.

[0036] The embodiments of the present application provide a method for preparing smart glasses and lenses.

[0037] In conjunction with the accompanying drawings, some embodiments of the present application are described in detail below. In the absence of conflict, the following embodiments and features in the embodiments can be combined with each other.

[0038] Please refer to Figure 1 , Figure 1 A schematic block diagram of the structure of an eye tracking device provided in one embodiment of the present application.

[0039] like Figure 1 As shown, the eye tracking device provided in the embodiment of the present application includes:

[0040] A lens assembly, the lens assembly comprising a lens body layer and a holographic medium layer, the holographic medium layer being arranged on the lens body layer, and the holographic medium layer recording interference information of information of an illumination light source beam for eye tracking;

[0041] A light source assembly, the light source assembly is used to provide a reproduction light beam for the holographic medium layer;

[0042] The illumination light source beam and the reproduction light beam are coherent, and the holographic medium layer is used to reproduce the illumination light source beam for eye tracking when irradiated by the reproduction light beam of the light source assembly.

[0043] Exemplarily, a holographic medium is a material that can record and store the amplitude and phase information of a light beam. When two coherent light beams are simultaneously irradiated on the holographic medium, the two light beams interfere with each other in the holographic medium, and relevant information such as the amplitude and phase of the light beams is stored in the holographic medium in the form of an interference pattern. When one of the light beams is irradiated on the interference pattern on the holographic medium again, the holographic medium can reproduce the other light beam.

[0044] The embodiment of the present application utilizes this characteristic of the holographic medium, arranges a holographic medium layer on the lens body layer, and records the information of the illumination light source beam used for eye tracking in the holographic medium layer. When eye tracking is required, the illumination light source beam can be reproduced by irradiating the holographic medium layer on the lens body layer with the reproduced light beam, so that the illumination light source beam forms a Purkinje image or interference fringes in the human eye, so as to determine the direction of the human eye's gaze according to the position of the Purkinje spot or the shape of the interference fringes, thereby realizing eye tracking.

[0045] Compared with the solution in the related art of arranging lamp beads on the lens body layer to emit illumination light beams, the holographic medium layer has extremely high transparency and will not block the user's line of sight, thereby increasing the visible area of ​​the lens.

[0046] Please refer to Figure 2 , Figure 2 A schematic block diagram of the structure of an eye tracking device provided in another embodiment of the present application.

[0047] like Figure 2 As shown, in some embodiments, the lens body layer includes an optical waveguide layer, and a coupling region is provided on the optical waveguide layer, and the coupling region is used to couple the reproduced light beam into the optical waveguide layer for transmission, so that the reproduced light beam irradiates the holographic medium layer.

[0048] Exemplarily, the lens body layer is used to form an optical waveguide, which is a structure used to transmit and guide a light beam, and can limit the light beam to a specific area for transmission, and transmit the virtual image to be displayed to the human eye. The embodiment of the present application uses an optical waveguide to transmit the reproduced light beam, so that the reproduced light beam can interfere with the light beam of the illumination light source set at any position.

[0049] Exemplarily, a coupling-in region is provided on the optical waveguide layer, which is used to couple the reproduced light beam into the optical waveguide layer for transmission, wherein the coupling-in region can be directly generated on the optical waveguide layer, or can be provided separately from the optical waveguide layer, and the structure of the coupling-in region can be a reflector, a prism, a surface relief grating, a volume holographic grating, etc., which are not limited here. Furthermore, the coupling-in region can also be used to couple the visible light signal into the optical waveguide for transmission, until it is transmitted to the coupling-out region and emitted to the human eye to generate a virtual image, which part is not drawn. Therefore, multiple coupling-in regions can be superimposed, and respond to the visible light signal and the infrared light signal respectively, so as to realize the functions of eye tracking illumination and virtual image display respectively.

[0050] Please refer to Figure 3 , Figure 3 A schematic block diagram of the structure of an eye tracking device provided in another embodiment of the present application.

[0051] like Figure 3 As shown, in some embodiments, the eye tracking device further includes:

[0052] A camera assembly is used to capture a target image formed by the illumination light source beam in a human eye, so as to perform eye tracking according to the target image based on a preset eye tracking algorithm.

[0053] Exemplarily, in order to perform eye tracking, it is necessary to capture a target image of the human eye through a camera assembly so as to determine the direction of the human eye's gaze based on the position of the Purkinje spots or the shape of the interference fringes in the target image based on a preset eye tracking algorithm to achieve eye tracking.

[0054] Exemplarily, the holographic medium layer is disposed on a side of the lens body layer close to or far from the human eye, and a first area of ​​the holographic medium layer is smaller than or equal to a second area of ​​the lens body layer.

[0055] Exemplarily, the holographic medium layer is attached to the lens body layer, and may be embedded in the lens body layer, or may be closely attached to and protrude from the lens body layer; the holographic medium layer may also have a certain distance from the lens body layer, which is not limited here.

[0056] In some embodiments, the illumination light source beam includes a first divergence angle beam and a second divergence angle beam, and the camera assembly is used to capture a Purkinje spot target image formed by the first divergence angle beam in a human eye, so as to perform eye tracking according to the Purkinje spot in the target image based on a preset eye tracking algorithm;

[0057] Alternatively, the camera assembly is used to capture the interference fringe image formed by the second divergence angle light beam in the human eye, so as to perform eye tracking according to the interference fringes in the target image based on a preset eye tracking algorithm;

[0058] The first divergence angle of the first divergence angle light beam is smaller than the second divergence angle of the second divergence angle light beam.

[0059] Please refer to Figure 4 , Figure 5 , Figure 4 A schematic diagram of a first divergent angle light beam provided in an embodiment of the present application; Figure 5 A schematic diagram of a target image illuminated by a first divergent angle light beam provided in an embodiment of the present application.

[0060] like Figure 4 , Figure 5 As shown, Figure 4 In the embodiment, a first divergence angle light beam with a smaller divergence angle is used as the illumination light source light beam, so as to form a relatively concentrated light spot on the surface of the cornea, that is, Figure 5 The Purkinje plaque shown in the figure can determine the direction of human eye gaze based on the position of the Purkinje plaque based on the preset eye tracking algorithm.

[0061] Please refer to Figure 6 , Figure 7 , Figure 6 A schematic diagram of a second divergent angle light beam provided in an embodiment of the present application; Figure 7 A schematic diagram of a target image illuminated by a second divergent angle light beam provided in an embodiment of the present application.

[0062] like Figure 6 , Figure 7 As shown, Figure 6 In the method, a second divergent angle light beam with a larger divergent angle is used as the illumination light source light beam, so as to form relatively concentrated interference fringes on the surface of the cornea. The second divergent angle light beam can be, for example, a structured light beam. Figure 7 As shown, due to the shape characteristics of the human eye, different forms of interference fringes will be formed when the human eye is looking in different directions. The preset eye tracking algorithm can determine the direction of the human eye's gaze according to the shape of the interference fringes.

[0063] In some embodiments, the illumination light source beam and the reproduction light beam are infrared beams.

[0064] Specifically, the wavelength range of the illumination light source beam and the reproduction light beam is 800 nm to 950 nm.

[0065] Exemplarily, in order to avoid interference with the virtual image to be displayed by the near-eye display device, the illumination light source beam and the reproduction light beam are both infrared beams invisible to the human eye. Accordingly, the target image based on the eye tracking can be obtained by an infrared camera.

[0066] In some embodiments, when the reproduced light beam of the light source assembly is irradiated onto the holographic medium layer, the holographic medium layer can reproduce a first exit angle light beam and a second exit angle light beam for eye tracking.

[0067] For example, in order to cover the sight lines of the human eye in all directions, the related art usually needs to set up multiple LED lamp beads to emit multiple illumination light source beams in different directions for eye tracking. In order to simulate the eye tracking effect of multiple LED lamp beads, the embodiment of the present application improves the flexibility of eye tracking by recording multiple illumination light source beams in different directions on the holographic medium layer. It can be understood that the first exit angle beam and the second exit angle beam have different exit angles.

[0068] It can be understood that in the eye tracking device provided in the embodiment of the present application, the illumination light source beam emitted by the holographic medium layer includes but is not limited to the first exit angle beam and the second exit angle beam, and may also include a third exit angle beam, a fourth exit angle beam, etc. The number of illumination light source beams with different exit angles can be set according to actual needs and is not limited here.

[0069] In some embodiments, the light source assembly is used to provide a first reproduction light beam and / or a second reproduction light beam to the holographic medium layer;

[0070] When the first reproduced light beam of the light source assembly is irradiated onto the holographic medium layer, the holographic medium layer can reproduce a first exit angle light beam for eye tracking; and / or

[0071] When the second reproduced light beam of the light source assembly irradiates the holographic medium layer, the holographic medium layer can reproduce a second exit angle light beam for eye tracking.

[0072] Exemplarily, in the related technology, the processor can separately control the LED lamp beads used for eye tracking, and control the number of lit LED lamp beads and the direction of the illumination light source beam according to actual needs. In order to enable the illumination light source beam emitted by the holographic medium layer to be adjusted according to actual needs, different illumination light source beams can be recorded through different reproduced beams. When it is necessary to emit an illumination light source beam in a certain direction, the light source module can be controlled to emit the corresponding reproduced beam, thereby improving the flexibility of the eye tracking device provided in the embodiment of the present application for eye tracking.

[0073] Specifically, when eye tracking is required through the first exit angle light beam, the first reproduced light beam is used to illuminate the holographic medium layer; when eye tracking is required through the second exit angle light beam, the second reproduced light beam is used to illuminate the holographic medium layer; when eye tracking is required through the first exit angle light beam and the second exit angle light beam, the first reproduced light beam and the second reproduced light beam are used to illuminate the holographic medium layer.

[0074] Exemplarily, the holographic medium layer may include a first holographic medium layer and a second holographic medium layer, the first exit angle light beam is recorded in the first holographic medium layer, and the second exit angle light beam is recorded in the second holographic medium layer. Of course, it is not limited to this. The first exit angle light beam and the second exit angle light beam may also be recorded in the same holographic medium, which is not limited here.

[0075] In some embodiments, the light source assembly includes a reconstruction light source and a dichroic mirror, and the dichroic mirror is used to change the angle of the reconstruction light beam of the reconstruction light source to obtain the first reconstruction light beam and the second reconstruction light beam.

[0076] Please refer to Figure 8 , Fig. 9 , Figure 8 A schematic diagram of a light beam with a first exit angle provided in an embodiment of the present application, Fig. 9 A schematic diagram of a light beam with a second exit angle provided in one embodiment of the present application.

[0077] like Figure 8 , Fig. 9 The light source module can adjust the angle of the dichroic mirror to change the angle at which the reproduction light beam emitted by the reproduction light source irradiates the holographic medium layer, thereby obtaining a first reproduction light beam and a second reproduction light beam with different angles, thereby respectively reproducing a first exit angle light beam and a second exit angle light beam through the first reproduction light beam and the second reproduction light beam, thereby improving the diversity of the illumination light source light beam and realizing eye tracking in different directions.

[0078] Please refer to Fig.10 , Fig.10 A schematic block diagram of a usage scenario of a lens preparation method provided in another embodiment of the present application.

[0079] like Fig.10 As shown, the present application also provides a method for preparing a lens, wherein the smart glasses include a lens assembly and a light source assembly, and the method for preparing the lens includes:

[0080] A holographic medium layer is provided on the lens body layer;

[0081] Irradiating the holographic medium layer with a preset illumination light source beam and a reproduction light source so that the illumination light source beam and the reproduction light source interfere with each other in the holographic medium layer, thereby obtaining interference information between the illumination light source beam and the reproduction light source;

[0082] Post-processing the holographic medium layer to fix the interference information to the holographic medium layer, so that when the reconstructed light beam of the light source assembly irradiates the holographic medium layer, the holographic medium layer can reconstruct an illumination light source beam for eye tracking;

[0083] The illumination light source beam and the reproduction light beam are coherent.

[0084] Illustratively, in the process of preparing the lens, the holographic medium layer is simultaneously irradiated with a reproduction light beam emitted by an infrared light source and an illumination light beam emitted by an illumination light source, the holographic medium layer is exposed to obtain corresponding interference fringes, and the holographic medium layer is post-processed, such as flood exposure, baking, etc., to fix the interference information in the holographic medium layer, so that when the holographic medium layer is subsequently irradiated with a reproduction light beam emitted by the infrared light source, the holographic medium layer can emit an illumination light beam for eye tracking.

[0085] Exemplarily, irradiating the holographic medium layer with a preset illumination light source beam and a reproduction light source beam of a light source module so that the illumination light source beam and the reproduction light source beam interfere with each other in the holographic medium layer, and obtaining interference information of the illumination light source beam and the reproduction light source beam includes:

[0086] The holographic medium layer is irradiated by a preset first exit angle light beam, a second exit angle light beam and a reproduction light beam of a light source module, so that the first exit angle light beam, the second exit angle light beam and the reproduction light beam interfere with each other in the holographic medium layer, and interference information for recording the first exit angle light beam, the second exit angle light beam and the reproduction light beam is obtained.

[0087] Exemplarily, the illumination light source beam recorded by the holographic medium layer may include multiple illumination light source beams at different angles, such as a first exit angle beam and a second exit angle beam, but this is not limited to this and may also include a third exit angle beam, etc. The number of exit angle beams may be set according to actual needs.

[0088] Exemplarily, illumination light source beams at different angles may interfere with each other through different reproduced beams, for example, a first reproduced beam may interfere with a first output angle beam, and a second reproduced beam may interfere with a second output angle beam. Thus, illumination light source beams at multiple different angles may be subsequently reproduced through different reproduced beams, thereby improving the flexibility of the illumination light source beams. Alternatively, the same reproduced beam may interfere with multiple illumination light source beams at different angles, which is not limited here.

[0089] In some embodiments, the embodiments of the present application further provide a near-eye display device, characterized in that the near-eye display device includes the eye tracking device described in any one of the embodiments of the present application.

[0090] Exemplarily, the near-eye display device includes a display device with an eye tracking function, such as smart glasses and a smart helmet.

[0091] In some embodiments, the near-eye display device further includes a visible light source for providing a virtual image for the near-eye display device.

[0092] Exemplarily, the near-eye display device displays a virtual image to the human eye through a visible light source, wherein the visible light source is spaced apart from the reproduction light source of the eye tracking device, and the visible light source can be arranged, for example, at Figure 8 , Fig. 9 The position shown is certainly not limited to this and is not limited here.

[0093] It can be understood that the description of the near-eye display device in the present application is only a partial structure of the near-eye display device. The specific near-eye display device may include more or fewer components than shown in the figure, or combine certain components, or have a different arrangement of components.

[0094] It should be understood that the terms used in this application specification are only for the purpose of describing specific embodiments and are not intended to limit the application. As used in this application specification and the appended claims, unless the context clearly indicates otherwise, the singular forms "a", "an" and "the" are intended to include plural forms.

[0095] It should also be understood that the term "and / or" used in the specification of this application and the appended claims refers to any combination of one or more of the associated listed items and all possible combinations, including these combinations. It should be noted that, in this article, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or system including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or system. In the absence of further restrictions, an element defined by the sentence "including a..." does not exclude the presence of other identical elements in the process, method, article or system including the element.

[0096] The serial numbers of the embodiments of the present application are for description only and do not represent the advantages and disadvantages of the embodiments. The above description is only a specific implementation mode of the present application, but the protection scope of the present application is not limited thereto. Any technician familiar with the technical field can easily think of various equivalent modifications or replacements within the technical scope disclosed in the present application, and these modifications or replacements should be included in the protection scope of the present application. Therefore, the protection scope of the present application shall be based on the protection scope of the claims.

Claims

1. An eye tracking device, characterized in that: The eye tracking device comprises: A lens assembly, the lens assembly comprising a lens body layer and a holographic medium layer, the holographic medium layer being arranged on the lens body layer, and the holographic medium layer recording interference information of an illumination light source beam for eye tracking; A light source assembly, the light source assembly is used to provide a reproduction light beam for the holographic medium layer; The illumination light source beam and the reproduction light beam are coherent, and the holographic medium layer is used to reproduce the illumination light source beam for eye tracking when irradiated by the reproduction light beam of the light source assembly.

2. The eye tracking device according to claim 1, characterized in that: The lens body layer includes an optical waveguide layer, on which a coupling-in region is arranged, and the coupling-in region is used to couple the reproduced light beam into the optical waveguide layer for transmission, so that the reproduced light beam irradiates the holographic medium layer.

3. The eye tracking device according to claim 1, characterized in that: The eye tracking device further comprises: A camera assembly is used to capture a target image formed by the illumination light source beam in a human eye, so as to perform eye tracking according to the target image based on a preset eye tracking algorithm.

4. The eye tracking device according to claim 3, characterized in that: The illumination light source beam includes a first divergence angle beam and a second divergence angle beam, and the camera assembly is used to capture a Purkinje spot target image formed by the first divergence angle beam in the human eye, so as to perform eye tracking according to the Purkinje spot in the target image based on a preset eye tracking algorithm; Alternatively, the camera assembly is used to capture the interference fringe image formed by the second divergence angle light beam in the human eye, so as to perform eye tracking according to the interference fringes in the target image based on a preset eye tracking algorithm; The first divergence angle of the first divergence angle light beam is smaller than the second divergence angle of the second divergence angle light beam.

5. The eye tracking device according to any one of claims 1 to 4, characterized in that: When the reproduced light beam of the light source assembly is irradiated onto the holographic medium layer, the holographic medium layer can reproduce a first light beam at an exit angle and a second light beam at an exit angle for eye tracking.

6. The eye tracking device according to claim 5, characterized in that: The light source assembly is used to provide a first reproduction light beam and / or a second reproduction light beam for the holographic medium layer; When the first reproduced light beam of the light source assembly irradiates the holographic medium layer, the holographic medium layer can reproduce a first exit angle light beam for eye tracking; and / or When the second reproduced light beam of the light source assembly irradiates the holographic medium layer, the holographic medium layer can reproduce a second exit angle light beam for eye tracking.

7. The eye tracking device according to claim 6, characterized in that: The light source assembly includes a reproducing light source and a dichroic mirror. The dichroic mirror is used to change the angle of the reproducing light beam of the reproducing light source to obtain the first reproducing light beam and the second reproducing light beam.

8. The eye tracking device according to any one of claims 1 to 4, characterized in that: The illumination light source beam and the reproduction light beam are infrared beams.

9. A near-eye display device, characterized in that: The near-eye display device comprises the eye tracking device according to any one of claims 1-8.

10. The near-eye display device according to claim 9, characterized in that: The near-eye display device also includes a visible light source, which is used to provide a virtual image for the near-eye display device.

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