Optical module and near-eye display device

Abstract

An embodiment of the present application provides an optical module and a near-eye display device; wherein, the optical module includes a display screen, a folded optical path component and an eye tracking component; the folded optical path component is arranged on the light-emitting side of the display screen, for guiding the light emitted by the display screen to the human eye, and the folded optical path component includes at least one lens; the eye tracking component includes a light source and a camera, the light source is arranged on the side of the edge area of the folded optical path component close to the display screen, and the lens between the light source and the human eye must satisfy: |min[1 / #imgabs0#]|≥5, wherein n is the number of lenses between the light source and the human eye, Ai is the curvature value of the surface of the i-th lens close to the human eye side within the range of 0.7~1 caliber, and Bi is the curvature value of the surface of the i-th lens away from the human eye side within the range of 0.7~1 caliber.

Description

Technical Field

[0001] The embodiments of the present application relate to the technical field of optical display systems. More specifically, the embodiments of the present application relate to an optical module and a near-eye display device. Background Art

[0002] With the continuous development of VR (virtual reality) technology, high definition, a wide field of view, and compact optical module design have become industry goals. However, with the reduction in screen size and increase in resolution, existing technologies require more lenses to correct aberrations and improve image quality. Furthermore, to balance the size and accuracy of the optical module, the eye tracking module is typically placed inside the module. However, the positional differences in the virtual image formed by the infrared light source after passing through multiple lenses can affect the accuracy of eye tracking calculations. Summary of the Invention

[0003] The purpose of this application is to provide a new technical solution for an optical module and a near-eye display device.

[0004] In a first aspect, an embodiment of the present application provides an optical module, comprising:

[0005] Display screen;

[0006] a folded optical path component, disposed on the light-emitting side of the display screen, for guiding the light emitted by the display screen to the human eye, the folded optical path component comprising at least one lens;

[0007] The eye tracking component includes a light source and a camera. The light source is arranged on the side of the edge area of the folded optical path component close to the display screen, and the lens between the light source and the human eye must meet the following requirements: |min[1 / ]|≥5, where n is the number of lenses between the light source and the human eye, Ai is the curvature value of the i-th lens surface close to the human eye within the range of 0.7 to 1 aperture, and Bi is the curvature value of the i-th lens surface away from the human eye within the range of 0.7 to 1 aperture.

[0008] Optionally, the folded optical path assembly includes a first lens;

[0009] The optical module includes a second lens and a third lens, and the second lens and the third lens are sequentially arranged between the first lens and the display screen, and all the lenses and the display screen are arranged along the same optical axis.

[0010] Optionally, the light sources are multiple and distributed in a ring shape in the edge area of the first lens close to the display screen, and the lens between the light source and the human eye satisfies: |min[1 / (A1-B1)]|≥5, where A1 is the curvature value of the surface of the first lens close to the human eye within the range of 0.7 to 1 aperture, and B1 is the curvature value of the surface of the first lens away from the human eye within the range of 0.7 to 1 aperture.

[0011] Optionally, the lens between the light source and the human eye further satisfies: |min[1 / (A1-B1)]|≤20.

[0012] Optionally, the folded optical path assembly includes a first lens;

[0013] The optical module includes a second lens, a third lens and a fourth lens. The fourth lens, the second lens and the third lens are sequentially arranged between the first lens and the display screen, and all the lenses and the display screen are arranged along the same optical axis.

[0014] Optionally, the light source is located in an edge area of the second lens close to the display screen and satisfies the following relationship: |min[1 / (A1-B1+A2-B2)]|≥5, where A1 is the curvature value of the surface of the first lens close to the human eye within a range of 0.7 to 1 aperture, B1 is the curvature value of the surface of the first lens away from the human eye within a range of 0.7 to 1 aperture, A2 is the curvature value of the surface of the fourth lens close to the human eye within a range of 0.7 to 1 aperture, and B2 is the curvature value of the surface of the fourth lens away from the human eye within a range of 0.7 to 1 aperture.

[0015] Optionally, the first lens and the fourth lens are glued together to form a glued lens group.

[0016] Optionally, the lens between the light source and the human eye further satisfies: |min[1 / (A1-B1+A2-B2)]|≤20.

[0017] Optionally, the folded optical path component further includes a beam splitter, a phase retarder and a polarization reflection element;

[0018] The beam splitter is disposed on a surface of the first lens close to the display screen, and the phase retarder and the polarization reflective element are sequentially disposed on a surface of the first lens away from the display screen.

[0019] Optionally, the folded optical path assembly further comprises a polarizing element, and the polarizing element is arranged on a surface of the polarizing reflective element that is away from the phase retarder;

[0020] The phase retarder, the polarized reflective element and the polarizing element form a composite film material.

[0021] Optionally, the light emitting surface of the display screen is provided with a protective glass, and the total thickness of the protective glass is ≥0.5 mm.

[0022] Optionally, the camera is disposed outside the display screen, and the camera is configured to receive infrared light emitted from the light source and reflected by the human eye.

[0023] In a second aspect, an embodiment of the present application provides a near-eye display device, the near-eye display device comprising:

[0024] casing; and

[0025] The optical module as described in the first aspect.

[0026] The beneficial effects of this application are:

[0027] The optical module provided in the embodiments of this application achieves a significant improvement in eye tracking accuracy while ensuring image quality through a specially designed optical architecture and optimized light source position of the eye tracking module, while maintaining the compactness and efficiency of the optical module. Specifically, the beneficial effects of this application are reflected in the following aspects:

[0028] (1) Significantly improve eye tracking accuracy:

[0029] By controlling the lens between the light source and the eye in the eye tracking component to meet a specific curvature relationship, |min[1 / (C1-C2)]|≥5, where C1 and C2 are the curvature values of the lens surface near and far from the eye, respectively, within a normalized aperture range of 0.7 to 1. This design effectively controls the propagation path of the light source in the optical module, significantly improving eye tracking positioning accuracy.

[0030] (2) Optimizing the infrared light propagation path:

[0031] Considering that the infrared light emitted by the light source in the eye tracking component primarily propagates through the edge region of the lens within the range of 0.7 to 1 aperture, this application specifically optimizes the curvature of this region. This optimization measure effectively reduces the interference of display light on the eye tracking signal, thereby further improving the accuracy and stability of eye tracking.

[0032] (3) Maintaining the compactness and efficiency of the optical module:

[0033] While achieving the aforementioned beneficial effects, this application does not sacrifice the compactness and efficiency of the optical module. By integrating the eye tracking component into the optical module through a rational optical architecture design, it not only ensures image quality but also enables precise eye tracking, meeting the requirements of modern near-eye display devices for high-performance and miniaturized optical modules.

[0034] Other features and advantages of the present specification will become apparent from the following detailed description of exemplary embodiments of the present specification with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the specification and, together with the description, serve to explain the principles of the specification.

[0036] Figure 1 This is one of the structural diagrams of the optical module provided in an embodiment of the present application;

[0037] Figure 2 for Figure 1 A schematic diagram of the assembly of the eye tracking component in the optical module is shown;

[0038] Figure 3 for Figure 1 The assembly relationship diagram of the display screen, light source and first lens of the optical module is shown;

[0039] Figure 4 A schematic diagram of a composite film material for an optical module provided in an embodiment of the present application;

[0040] Figure 5 for Figure 1 The dot array diagram of the optical module is shown;

[0041] Figure 6 for Figure 1 MTF diagram of the optical module shown;

[0042] Figure 7 for Figure 1 Field curvature and optical distortion diagram of the optical module shown;

[0043] Figure 8 for Figure 1 A vertical axis chromatic aberration diagram of the optical module shown;

[0044] Figure 9 The second structural diagram of the optical module provided in the embodiment of the present application;

[0045] Figure 10 for Figure 9 A schematic diagram of the assembly of the eye tracking component in the optical module is shown;

[0046] Figure 11 for Figure 9 The dot array diagram of the optical module is shown;

[0047] Figure 12 for Figure 9 MTF diagram of the optical module shown;

[0048] Figure 13 for Figure 9 Field curvature and optical distortion diagram of the optical module shown;

[0049] Figure 14 for Figure 9 A vertical axis chromatic aberration diagram of the optical module shown;

[0050] Figure 15 The third structural diagram of the optical module provided in the embodiment of the present application;

[0051] Figure 16 for Figure 15 A schematic diagram of the assembly of the eye tracking component in the optical module is shown;

[0052] Figure 17 for Figure 15 The dot array diagram of the optical module is shown;

[0053] Figure 18 for Figure 15 MTF diagram of the optical module shown;

[0054] Figure 19 for Figure 15 Field curvature and optical distortion diagram of the optical module shown;

[0055] Figure 20 for Figure 15 The vertical axis chromatic aberration diagram of the optical module is shown.

[0056] Description of reference numerals:

[0057] 1. Display screen; 2. First lens; 21. First surface; 211. Beam splitter; 22. Second surface; 221. Anti-reflection film; 222. Polarizing element; 223. Polarized reflective element; 224. Phase retarder; 3. Second lens; 31. Third surface; 32. Fourth surface; 4. Third lens; 41. Fifth surface; 42. Sixth surface; 5. Fourth lens; 51. Seventh surface; 52. Eighth surface; 6. Light source; 7. Camera; 01. Human eye. DETAILED DESCRIPTION

[0058] Various exemplary embodiments of the present application will now be described in detail with reference to the accompanying drawings. It should be noted that unless otherwise specifically stated, the relative arrangements of components and steps, numerical expressions and numerical values set forth in these embodiments do not limit the scope of the present application.

[0059] The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way intended to limit the present disclosure, its application, or uses.

[0060] Techniques and equipment known to ordinary technicians in the relevant art may not be discussed in detail, but where appropriate, the techniques and equipment should be considered part of the specification.

[0061] In all examples shown and discussed herein, any specific values should be interpreted as merely exemplary and not limiting. Therefore, other examples of the exemplary embodiments may have different values.

[0062] It should be noted that like reference numerals and letters refer to like items in the following figures, and therefore, once an item is defined in one figure, it need not be further discussed in subsequent figures.

[0063] The optical module and near-eye display device provided in the embodiments of the present application are described in detail below with reference to the accompanying drawings.

[0064] According to one embodiment of the present application, an optical module is provided, comprising: a display screen 1, a folded optical path component, and an eye tracking component. The folded optical path component is disposed on the light-emitting side of the display screen 1, and is used to guide the light emitted by the display screen 1 to the human eye 01. The folded optical path component includes at least one lens. The eye tracking component includes a light source 6 and a camera 7. The light source 6 is disposed on the edge of the folded optical path component, close to the display screen 1. The lens between the light source 6 and the human eye 01 must meet the following requirements: |min[1 / ]|≥5, wherein n is the number of lenses between the light source 6 and the human eye 01, Ai is the curvature value of the i-th lens close to the human eye side surface within the range of 0.7~1 diameter, and Bi is the curvature value of the i-th lens away from the human eye side surface within the range of 0.7~1 diameter.

[0065] In traditional optical systems, especially VR optical systems, the light source (such as an infrared LED) in the eye tracking module is usually placed in front of the screen. In this layout, the infrared light emitted by the light source needs to be refracted and reflected by multiple lenses before it can enter the human eye. It is then reflected by the human eye to the camera for eye position tracking. However, due to the influence of the lens curvature in the optical system, the light path of different field angles will be different. This difference will cause the virtual image position to deviate. This deviation is a common and difficult-to-solve problem in traditional VR optical systems. It significantly reduces the accuracy of eye tracking and affects the interactive experience and performance of VR optical devices.

[0066] To address this challenge, the present invention provides a novel optical module design. By optimizing the lens layout and optical parameter design within the optical architecture, this module specifically fine-tunes the curvature of the edge regions of key lenses that influence eye tracking accuracy (i.e., one or more lenses between the eye 01 and the light source 6). This design effectively addresses the difficulty in balancing aberration correction and eye tracking accuracy in traditional VR optical systems.

[0067] According to one embodiment of the present application, an optical module is provided that mainly includes a display screen 1, a folded optical path component, and an eye tracking component. The following is a detailed analysis of each component and key parts.

[0068] The optical module provided in the embodiment of the present application includes a display screen 1, see Figure 1 The display screen 1 serves as the image source of the optical module, and is responsible for generating and emitting light for imaging display.

[0069] In the optical module provided in the embodiment of the present application, the size of the display screen 1 is relatively small.

[0070] With the development of virtual reality (VR) technology, users are placing higher demands on the portability and wearing comfort of optical display devices, especially near-eye displays (such as smart glasses or smart headsets). Smaller display sizes help reduce the size and weight of optical modules, making the resulting optical display devices lighter and improving user comfort. Furthermore, smaller display sizes facilitate optimized optical module design. This allows for a more compact layout of optical components such as lenses in the folded optical path assembly, reducing light loss and distortion during transmission, thereby improving overall optical performance.

[0071] The optical module provided in the embodiment of the present application includes a folded optical path component, see Figure 1 The folded optical path component is arranged on the light-emitting side of the display screen 1 (see Figure 1 ), which is mainly used to guide the light emitted by the display screen 1 and fold it multiple times before entering the human eye 01, and finally transmit the image light to the human eye 01, which can improve the imaging quality.

[0072] See also Figure 1 、 Figure 9 and Figure 15 In the optical module provided in the embodiment of the present application, the folded light path is located near the human eye. It should be noted that the number of lenses in the folded light path assembly is not fixed, but can be adjusted according to actual needs. In the optical module provided in the embodiment of the present application, the folded light path can pass through only one lens (such as the first lens 2, see Figure 1 and Figure 9), or it can pass through two or more lenses (for example, to achieve higher imaging quality or a more complex optical path layout). This flexibility enables the optical module of this application to adapt to different application scenarios and needs.

[0073] The folded optical path assembly in the embodiment of the present application includes one, two, three, four or more lenses, see Figure 1 、 Figure 9 and Figure 15 These lenses achieve the folding and transmission of light through precise arrangement and optical parameter design. Figure 1 and Figure 9 The first lens 2 is one of the key components and is located between the display screen 1 and the human eye 01.

[0074] See also Figure 1 and Figure 4 The folded optical path component can use only one lens, namely the first lens 2. This basic lens configuration is combined with multiple optical film materials, a spectrometer 211, a phase delay 224 and a polarization reflection element 223, etc., which can already achieve basic light folding and transmission functions. This design is suitable for some application scenarios that do not have particularly high requirements for image quality, and it can fully meet the user's visual needs.

[0075] When higher image quality is required, an additional lens can be selectively added between the first lens 2 and the display screen 1. For example, see Figure 9 , a second lens 3 and a third lens 4 are added. For another example, see Figure 15 ,exist Figure 9 On the basis of , a fourth lens 5 is added. The addition of these additional lenses can further correct aberrations and improve image quality.

[0076] According to actual needs, see Figure 9 and Figure 15 , 1 to 3 lenses, or even more, can be added between the first lens 2 and the display screen 1. However, the increase in the number of lenses is not unlimited, because too many lenses will increase the volume, weight and production cost of the entire optical module.

[0077] As the number of lenses increases, the optical module can more effectively correct various aberrations, such as spherical aberration and chromatic aberration, thereby improving overall image quality. This is crucial for achieving high-definition near-eye displays.

[0078] After comprehensively considering the balance between image quality improvement and the volume, weight, and production cost of the optical module, it is preferred to add one to three lenses between the first lens 2 and the display screen 1. This configuration can improve image quality to a certain extent without excessively increasing the volume and weight of the entire optical module, while maintaining relatively low production costs.

[0079] The folded optical path assembly in the embodiment of the present application can adjust the direction of the light emitted by the display screen 1, folding the light that originally propagated in a straight line. This folding effect allows the light to change its propagation direction multiple times within a limited space. By folding and adjusting the direction of light, the folded optical path assembly enables the optical module to achieve efficient light transmission in a smaller space. In addition, precise light direction adjustment helps reduce the loss and distortion of light during propagation, thereby improving the overall imaging quality of the optical module, which is crucial for enhancing the immersion of the VR visual experience.

[0080] The optical module provided in the embodiment of the present application also includes an eye tracking component, see Figure 2 and Figure 3 The eye tracking component includes a light source 6 and a camera 7.

[0081] There are multiple light sources 6. The light sources 6 are, for example, infrared LEDs.

[0082] Wherein, the camera 7 can be provided with one. The camera 7 is an infrared camera.

[0083] See also Figure 2 The light source 6 is positioned on the optical path between the edge of the first lens 2 in the folded optical path assembly and the human eye 01. This position is designed based on the specific requirements of eye tracking technology, which requires that the light emitted by the light source 6 can illuminate the human eye 01 and be reflected to the camera 7.

[0084] More importantly, the optical design provided in the embodiment of the present application controls the curvature relationship of the lens between the light source 6 and the human eye 01. Specifically, the lens between the light source 6 and the human eye 01 (see Figure 1 and Figure 9 , mainly refers to the first lens 2; as shown in Figure 15 , mainly refers to the first lens 2 and the fourth lens 5) must meet a specific curvature relationship, namely |min[1 / ]|≥5. In this relationship, Ai is the curvature of the i-th lens surface near the human eye within a range of 0.7 to 1 aperture, and Bi is the curvature of the i-th lens surface away from the human eye within a range of 0.7 to 1 aperture. This curvature relationship is designed to control the difference in the imaging position of the infrared light emitted by the light source 6 after passing through the edge areas of the involved lenses, thereby improving the accuracy of eye tracking.

[0085] Furthermore, in order to ensure the accuracy of eye tracking, the present application makes changes to the key lenses that affect the accuracy of eye tracking, such as the first lens 2 (see Figure 1 and Figure 9 ) The curvature of the edge area of the lens is finely controlled. This design rationally constrains the curvature difference of the edge area of the lens, thereby ensuring that the propagation path of the infrared light emitted by light source 6 after passing through the lens is more stable, reducing the position deviation of the virtual image caused by lens aberration.

[0086] By optimizing the curvature of all lens edge regions between the eye 01 and the light source 6, the optical design provided in this embodiment effectively reduces distortion of infrared light during propagation. This improvement allows infrared light to more accurately travel along the pre-defined optical path to the eye 01 after passing through the lens edge region, thereby improving the stability of eye tracking.

[0087] Eye tracking primarily relies on the propagation characteristics of the infrared light emitted by light source 6 through the lens edge region. Because the curvature of this lens edge region has been meticulously optimized, the positional shift of the virtual image due to lens aberrations is significantly reduced. Consequently, camera 7 in the eye tracking assembly can more accurately capture the infrared signal reflected by eye 01, thereby improving eye tracking accuracy.

[0088] Experimental data shows that optimizing the curvature of the lens edge area using this design can reduce eye tracking position errors by over 30%. This significant improvement is particularly suitable for applications such as high-precision gaze tracking, providing a more accurate and reliable eye tracking solution for VR optical display devices.

[0089] It should be noted that the number of lenses in the optical module of the present embodiment is not fixed but can be adjusted according to design requirements. Changing the number of lenses directly changes the light propagation path, thereby affecting the optimal placement of light source 6. The position of light source 6 needs to be adaptively adjusted based on the specific number and layout of lenses to ensure that infrared light can be efficiently transmitted to the human eye 01 and accurately captured by camera 7 after reflection.

[0090] For example, see Figure 15When the optical module includes four lenses, the position of the light source 6 changes significantly. Specifically:

[0091] In this case, the light source 6 is placed between the fourth lens 5 and the edge of the second lens 3. This means that there are two lenses between the light source 6 and the eye 01: the first lens 2 and the fourth lens 5. This placement is based on considerations for optimizing the light propagation path and improving eye tracking accuracy. Once the position of the light source 6 is determined, the first lens 2 and the fourth lens 5 located between it and the eye 01 must also be controlled simultaneously. This is because these two lenses have a significant impact on the light propagation path and image quality. By finely controlling the curvature relationship of the edge regions of these two lenses, light propagation characteristics can be further optimized, aberrations and distortion can be reduced, and eye tracking accuracy can be improved.

[0092] In the eye tracking component provided in the embodiment of the present application, the camera 7 is matched with the light source 6 to achieve an efficient and accurate eye tracking function. The following is a description of the position of the camera 7 and its function.

[0093] In the eye-tracking assembly provided in this embodiment, camera 7 is positioned to the side (outside the edge) of display screen 1. This placement is designed for both space utilization and tracking efficiency. The position of camera 7 is relatively fixed within the entire optical module, ensuring stable tracking performance in various scenarios.

[0094] In this application, since the size of the display screen 1 is designed to be relatively small, this provides sufficient space for the installation of the camera 7. Figure 2 、 Figure 10 and Figure 16 The outer area of the display screen 1 is sufficient to accommodate the camera 7 without causing any interference to its normal display function.

[0095] Camera 7 is used to receive infrared light reflected from eye 01. This infrared light is emitted by light source 6 in the eye tracking assembly and guided by optical components such as a lens assembly before being projected onto eye 01. The infrared light reflected from eye 01 carries key information about eye position. After receiving the infrared light, camera 7 processes it to extract key features reflecting eye position.

[0096] Based on the processing and analysis of the received infrared light, the camera 7 can accurately track the position of the human eye. This function provides real-time eye position information for VR optical display devices, providing optical support for subsequent applications such as interactive control and gaze tracking.

[0097] In this embodiment of the present application, the camera 7 is positioned to the side of the display screen 1, taking full advantage of the smaller display screen size and improving the space utilization of the optical module. The location of the camera 7 allows it to more directly receive infrared light reflected by the human eye 01, thereby improving tracking efficiency.

[0098] In general, the optical module provided in the embodiment of the present application can improve the eye tracking accuracy. By controlling the curvature relationship of the lens between the light source 6 and the human eye 01 (min[1 / ]|≥5), effectively reducing the difference in the imaging position of the light emitted by light source 6 after passing through the edge area of the lens. This design enables camera 7 to more accurately receive infrared light reflected by the human eye 01, thereby improving eye tracking accuracy. This is crucial for achieving a high-precision VR interactive experience.

[0099] Furthermore, the design of the folded optical path assembly makes the overall structure of the optical module of the present application more compact and efficient. By rationally arranging the lenses and eye tracking components, precise control of light propagation is achieved while maintaining the lightness and ease of use of the optical module.

[0100] The high-precision eye tracking function enables optical display devices to more accurately respond to user movements and changes in line of sight, providing a more immersive interactive experience. At the same time, the compact optical module design also improves the wearing comfort of the device.

[0101] The optical module provided in the embodiment of the present application has an MTF (modulation transfer function) greater than 0.1 at 10lp / mm, an absolute value of distortion less than 45%, and a vertical axis chromatic aberration less than 250μm, which fully meets the requirements of high-definition display.

[0102] In some examples of this application, see Figure 9 , the folded optical path component includes a first lens 2;

[0103] The optical module includes a second lens 3 and a third lens 4 , and the second lens 3 and the third lens 4 are sequentially arranged between the first lens 2 and the display screen 1 , and all the lenses and the display screen 1 are arranged along the same optical axis.

[0104] See also Figure 9 The folded optical path component includes a lens, namely a first lens 2. At this time, a second lens 3 and a third lens 4 are also introduced into the optical module, and the second lens 3 and the third lens 4 are sequentially arranged between the first lens 2 and the display screen 1, and all the lenses and the display screen 1 are arranged along the same optical axis.

[0105] In the examples provided in this application, see Figure 9 This example includes three lenses: a first lens 2 on the side closest to the eye, a third lens 4 on the side closest to the display screen, and a second lens 3 located between the first and third lenses 2 and 4. These three lenses are arranged along the same optical axis as the display screen 1. By increasing the number of lenses, imaging quality can be improved.

[0106] In the optical module, all lenses are arranged along the same optical axis as the display screen 1, ensuring the stability and consistency of light during propagation. This layout helps reduce the deflection and scattering of light between lenses, thereby improving the clarity and contrast of imaging.

[0107] In the optical module, the second lens 3 and the third lens 4 are sequentially positioned between the first lens 2 and the display screen 1. This lens layout is based on considerations for light correction and image quality optimization. Each lens performs a specific optical function, such as correcting aberrations and magnifying images. By combining them in a reasonable order, they can achieve optimal optical effects.

[0108] By adding the second lens 3 and the third lens 4, the aberration and distortion generated during the propagation of light can be further corrected. The combination of these lenses can significantly improve the clarity and resolution of the image, allowing users to enjoy a better visual experience.

[0109] According to this example of the present application, see Figure 3 The entire optical module uses three lenses to coordinately correct aberrations and improve image quality. Figure 11 In this example, the maximum value of the optical module's point array image point is <37μm, which is fully capable of meeting high-definition display requirements.

[0110] In some examples of this application, see Figure 3 The light sources 6 are multiple and distributed in a ring shape at the edge of the first lens 2 close to the display screen 1, and the lens between the light source 6 and the human eye 01 satisfies the following conditions: |min[1 / (A1-B1)]|≥5, where A1 is the curvature value of the surface of the first lens 2 close to the human eye within a range of 0.7 to 1 aperture, and B1 is the curvature value of the surface of the first lens 2 away from the human eye within a range of 0.7 to 1 aperture.

[0111] In the example provided in this application, the light sources 6 are distributed in the edge area of the first lens 2 close to the display screen 1, forming a ring array. The advantages of this layout design are:

[0112] The ring-shaped light source illuminates the eye 01 from various angles, ensuring consistent infrared coverage regardless of gaze direction, reducing tracking blind spots. The camera 7 captures a more uniform corneal reflection spot, improving algorithm positioning accuracy. Furthermore, the light source 6 is located at the edge of the lens rather than the center of the optical path to avoid interfering with the display optical path. The curvature of the lens edge is also utilized to control the light propagation path.

[0113] In this example of the application, see Figure 3 The lens between the light source 6 and the human eye 01 is the first lens 2. In this case, virtual image offset can be reduced by controlling |min[1 / (A1-B1)]| ≥ 5. However, it should be noted that the lens design freedom should not be overly constrained, otherwise it will increase the size or cost of the optical module. Therefore, in this example of the present application, the upper limit of |min[1 / (A1-B1)]| is also controlled, namely |min[1 / (A1-B1)]| ≤ 20. In general, 5 ≤ |min[1 / (A1-B1)]| ≤ 20.

[0114] In some examples of the present application, the lens between the light source 6 and the human eye 01 further satisfies: |min[1 / (A1-B1)]|≤20.

[0115] The lens curvature condition of |min[1 / (A1-B1)]|≤20 is introduced to optimize the propagation path of infrared light through the first lens 2. By precisely controlling the curvature differences in the edge region of the first lens 2, for example, deflection and scattering of infrared light during propagation can be reduced, thereby improving image quality. This curvature condition also helps reduce virtual image position shifts caused by lens aberrations. This also has a positive effect on improving the accuracy and stability of eye tracking.

[0116] In some examples of this application, see Figure 15 and Figure 16 , the folded optical path component includes a first lens 2;

[0117] The optical module includes a second lens 3, a third lens 4 and a fourth lens 5. The fourth lens 5, the second lens 3 and the third lens 4 are sequentially arranged between the first lens 2 and the display screen 1, and all the lenses are arranged along the same optical axis as the display screen 1.

[0118] In the examples provided in this application, see Figure 15 and Figure 16The optical module's optical structure design has been further expanded. In this example, the folded optical path assembly includes a first lens 2. Furthermore, a fourth lens 5, a second lens 3, and a third lens 4 are positioned between the folded optical path and the display screen 1. These four lenses work synergistically within the entire optical module, improving image quality. All lenses within the optical module are positioned along the same optical axis as the display screen 1.

[0119] Specifically, see Figure 15 and Figure 16 , compared to Figure 1 The optical module shown in the figure adds three lenses to the optical module: a second lens 3, a third lens 4, and a fourth lens 5. The folded optical path assembly achieves a multi-lens design, such as the combination of the first lens 2 and the fourth lens 5. This design can more precisely correct aberrations and distortions generated during light propagation, thereby improving imaging quality.

[0120] In the optical module provided in this example of the present application, all lenses are arranged along the same optical axis as the display screen 1, ensuring the stability and consistency of light during propagation. This layout helps reduce the deflection and scattering of light between lenses, improving the clarity and contrast of the image.

[0121] According to this example of the present application, the design of a combination of multiple lenses (such as two lenses: a first lens 2 and a fourth lens 5) can more comprehensively correct light aberrations and distortions. As the number of lenses increases, the imaging quality is significantly improved, and users can enjoy a more delicate and realistic visual experience. The lens layout arranged along the same optical axis reduces the loss of light during propagation. Since the deflection and scattering of light between lenses are effectively controlled, more light can be transmitted more smoothly to the human eye 01, improving the efficiency of the optical module. The design of a multi-lens combination helps to more accurately control the propagation path and imaging position of light, thereby improving the accuracy and stability of eye tracking.

[0122] Furthermore, compared to a single-lens optical design, a four-lens optical design provides greater design flexibility for optical modules. Optical engineers can flexibly adjust lens parameters such as number, type, and curvature to achieve optimal optical effects and performance based on specific application scenarios and requirements.

[0123] In some examples of this application, see Figure 15 and Figure 16The light source 6 is located in the edge area of the second lens 3 on the side close to the display screen 1 and satisfies the following relationship: |min[1 / (A1-B1+A2-B2)]|≥5, where A1 is the curvature value of the surface of the first lens 2 close to the human eye within a range of 0.7 to 1 aperture, B1 is the curvature value of the surface of the first lens 2 away from the human eye within a range of 0.7 to 1 aperture, A2 is the curvature value of the surface of the fourth lens 5 close to the human eye within a range of 0.7 to 1 aperture, and B2 is the curvature value of the surface of the fourth lens 5 away from the human eye within a range of 0.7 to 1 aperture.

[0124] In the examples provided in this application, see Figure 15 and Figure 16 The light source 6 in the eye-tracking assembly is placed between the fourth lens 5 and the edge of the second lens 3. Furthermore, the optical design specifies a curvature relationship between the edge of the two lenses between the light source 6 and the eye 01: |min[1 / (A1-B1+A2-B2)]|≥5. The following is a detailed analysis of the technical effectiveness of this design.

[0125] It should be noted that, in the optical module provided in the embodiment of the present application, the curvature of the edge area of all lenses included between the light source 6 and the human eye 01 needs to be precisely controlled.

[0126] See also Figure 15 and Figure 16 The light source 6 is placed at the edge of the fourth lens 5, facing away from the first lens 2. This placement is designed to optimize the light propagation path and improve eye tracking accuracy. Placing the light source 6 in this position effectively reduces multiple reflections and scattering of light within the first lens 2 and the fourth lens 5, thereby improving light utilization and eye tracking accuracy.

[0127] By introducing a curvature relationship of |min[1 / (A1-B1+A2-B2)]|≥5 between the first lens 2 and the fourth lens 5, the propagation path of the infrared light emitted by the light source 6 through the fourth lens 5 and the first lens 2 can be precisely controlled. This curvature relationship helps reduce deflection and scattering of infrared light at the lens edges, thereby improving image quality. Precisely controlling the curvature relationship of these two lens edges effectively reduces virtual image position shifts caused by lens aberrations and distortion. This is crucial for improving the accuracy and stability of eye tracking.

[0128] Because the position of the light source 6 and the curvature of the two lenses through which the infrared light passes have been optimized, the accuracy of eye tracking has been significantly improved. This high-precision eye tracking capability is crucial for achieving a more natural and immersive VR experience.

[0129] In some examples of this application, see Figure 15 The first lens 2 and the fourth lens 5 are glued together to form a glued lens group.

[0130] See also Figure 15 When the optical module includes multiple lenses, such as four lenses, the two lenses closest to the eye, namely the first lens 2 and the fourth lens 5, can be cemented together to form a folded optical path assembly. This design significantly reduces aberrations and distortions caused by limitations in individual lens materials or curvature. Lenses made of different materials have different dispersion characteristics, and proper combination can compensate for these dispersions, improving image quality.

[0131] Because the cemented lens group can reduce aberrations and distortion and optimize the light propagation path, it can significantly improve image quality. Users can enjoy a clearer, more detailed and realistic visual experience.

[0132] The bonded lens assembly firmly bonds the two lenses together to form a single unit, enhancing the stability and reliability of the optical module. This prevents lens loosening or displacement over long periods of use, ensuring stable operation of the optical module.

[0133] The use of a cemented lens assembly can also simplify the optical design of an optical module to a certain extent. For example, the optical functions of multiple independent lenses can be integrated into a single cemented lens assembly, thereby reducing the number and complexity of lenses, lowering manufacturing costs and difficulty.

[0134] It should be noted that infrared light (such as the light source 6 used for eye tracking) is more sensitive to changes in lens curvature due to its longer wavelength. By precisely controlling the curvature relationship between the edge regions of the first lens 2 and the fourth lens 5, through which the infrared light passes, it is possible to ensure that the infrared light is more stably focused on the human eye 01 during its propagation. This not only improves eye tracking accuracy but also helps reduce errors caused by light deflection and scattering.

[0135] The optimized curvature of the lens edge effectively reduces light deflection and scattering at the lens edge. This is beneficial for all wavelengths of light, but is particularly important for infrared light. Because infrared light has relatively low energy, any slight loss can result in a significant drop in signal strength.

[0136] It's worth noting that, while the light used for imaging and display primarily passes through the central field of view of the lens, the optical design in this application primarily regulates the curvature of the lens's edge regions. Therefore, this design ensures stable focus of the infrared light without significantly affecting the propagation path and image quality of the imaging and display light. This ensures that users can enjoy a high-quality visual experience while also obtaining high-precision eye tracking capabilities.

[0137] In some examples of the present application, the light source 6 further satisfies: |min[1 / (A1-B1+A2-B2)]|≤20.

[0138] In the examples provided herein, in addition to the previously mentioned lens bonding design and meticulous control of lens edge curvature, an upper limit condition is imposed on the lens curvature relationship between the light source 6 and the human eye 01: |min[1 / (A1-B1+A2-B2)]|≤20. This design control has significant technical benefits for optimizing optical module performance, improving eye tracking accuracy, and ensuring image quality. In other words, 5≤|min[1 / (A1-B1+A2-B2)]|≤20.

[0139] By setting this upper limit, the range of variation in the optical path difference of the infrared light emitted by the light source 6 as it passes through the fourth lens 5 and the first lens 2 can be constrained, thereby ensuring the stability and focusing accuracy of the infrared light during propagation. By setting this upper limit, the propagation path of the infrared light emitted by the light source 6 through the lens can be further optimized, reducing the impact of light deflection and scattering on tracking accuracy.

[0140] Although this upper limit condition is mainly aimed at optimizing the propagation path of infrared light, since visible light and infrared light have similar propagation characteristics in the lens, this design also helps to ensure the normal propagation of imaging display light and high-quality imaging.

[0141] In this application, the curvature design of the lens edge region is a critical aspect, affecting the propagation of visible light and the final image quality. In particular, it significantly impacts the optical path difference of infrared light emitted by light source 6 (e.g., the infrared light source used for eye tracking). By finely controlling the curvature of the edge regions of all lenses through which infrared light passes, the optical path difference of infrared light passing through the lens can be effectively reduced (minimized), thereby improving eye tracking accuracy and the overall performance of the optical module.

[0142] In other words, by finely controlling the curvature of the edge regions of all lenses through which infrared light passes, this application significantly reduces the optical path difference of infrared light as it passes through the lenses. This technical effect not only improves the accuracy of eye tracking and the overall performance of the optical module, but also provides new ideas and methods for the design of optical modules.

[0143] In some examples of this application, see Figure 1 and Figure 4 The folded optical path component also includes a spectrometer 211, a phase retarder 224 and a polarization reflection element 223; the spectrometer 211 is arranged on the surface of the first lens 2 close to the display screen 1, and the phase retarder 224 and the polarization reflection element 223 are arranged in sequence on the surface of the first lens 2 away from the display screen 1.

[0144] See also Figure 1 、 Figure 9 and Figure 15 The beam splitter 211 is disposed on the first surface 21 of the first lens 2 and is, for example, a semi-transparent and semi-reflective film. The beam splitter 211 can transmit a portion of the light while reflecting a portion of the light, thereby splitting the light into different paths or changing the propagation direction of the light.

[0145] See also Figure 4 The phase retarder 224 and the polarizing reflective element 223 form a part of a composite film material and are disposed on the second surface 22 of the first lens 2. The phase retarder 224 is, for example, a quarter-wave plate. The polarizing reflective element 223 is a polarizing reflective film.

[0146] Phase retarder 224 is used to phase-delay light and change its polarization state. This is a key component for achieving specific optical functions, such as circular polarization conversion. For example, phase retarder 224 is used to convert linearly polarized light into circularly polarized light, or vice versa.

[0147] The polarized reflective element 223 can reflect or transmit light according to its polarization state.

[0148] In some examples of the present application, the folded optical path assembly further includes a polarizing element 222, which is disposed on a surface of the polarizing reflective element 223 facing away from the phase retarder 224; wherein the phase retarder 224, the polarizing reflective element 223 and the polarizing element 222 constitute a composite film material.

[0149] The polarizing element 222 is an optical element that can filter out light of a specific polarization direction. In the optical design of the present application, the polarizing element 222 can be used to further purify the light reflected by the polarizing reflective element 223, ensuring that only light of a specific polarization direction can continue to propagate.

[0150] By integrating the phase retarder 224, the polarized reflective element 223, and the polarizing element 222 into a composite film, light can be utilized more efficiently. The phase retarder 224 converts incident light into a specific polarization direction, the polarized reflective element 223 selectively reflects light in that polarization direction, and the polarizing element 222 further purifies the reflected light, reducing light loss and improving overall light utilization efficiency.

[0151] Stray light and ghosting are common problems in optical modules, reducing image clarity and contrast. The composite film in this application effectively reduces these issues by selectively reflecting and transmitting light with specific polarization directions, thereby improving image purity and clarity.

[0152] Furthermore, integrating the phase retarder 224, polarized reflective element 223, and polarizing element 222 into a composite film can also simplify the optical design. This integrated design reduces the number and complexity of optical components, lowering manufacturing costs and difficulty while improving the stability and reliability of the optical module.

[0153] Optionally, the composite film material may further include an anti-reflection film 221, see Figure 4 .

[0154] Anti-reflection coatings are thin films applied to the surface of optical components to reduce light reflection and increase light transmittance. They improve light transmission efficiency by reducing reflections caused by differences in refractive index when light travels from one medium to another.

[0155] In the composite film provided herein, the anti-reflection film 221 can effectively reduce light reflection losses on the surface of optical elements (such as the first lens 2). The application of the anti-reflection film 221 can significantly increase light transmittance, allowing more light to travel along the designed path and ultimately enter the human eye 01, thereby improving image brightness and contrast.

[0156] Reducing reflected light not only improves light transmittance but also helps reduce glare and stray light. These can reduce image clarity and contrast, impacting the user's visual experience. The anti-reflective film 221 effectively suppresses these undesirable rays, improving image purity and quality.

[0157] The anti-reflection film can also serve as a protective layer, providing an additional layer of protection for the optical element and extending its service life.

[0158] In the composite film provided herein, the anti-reflection film 221 works in conjunction with other optical elements (such as the phase retarder 224, the polarizing reflective element 223, and the polarizing element 222) to optimize optical performance. By reducing reflections and increasing transmittance, the anti-reflection film 221 facilitates more precise light control and higher-quality imaging.

[0159] In some examples of the present application, a protective glass is provided on the light-emitting surface of the display screen 1. The total thickness of the protective glass is ≥0.5 mm.

[0160] In the example of this application, the number of protective glasses provided in front of the display screen 1 should be ≥ 1. Multiple layers of protective glass can provide more comprehensive protection and further enhance the durability and impact resistance of the display screen.

[0161] The total thickness of the protective glass should be ≥0.5mm. This thickness requirement is based on a comprehensive consideration of the physical and optical properties of the protective glass, aiming to ensure that the protective glass can provide sufficient physical protection while minimizing the impact on light transmittance.

[0162] By providing protective glass, the chance of user fingers or other objects directly contacting the display surface is reduced, thereby reducing the risk of screen damage caused by friction, scratches, etc.

[0163] According to the optical module provided in the embodiment of the present application, see Figure 1 , the optical path propagation process is as follows:

[0164] Initial light source: Light is first emitted by the display screen 1. The light can be natural light, but is usually converted into circularly polarized light to facilitate subsequent optical processing.

[0165] After first passing through phase retarder 224, the circularly polarized light then propagates to the second surface 22 of the lens assembly, which is equipped with a phase retarder 224 (e.g., a quarter-wave plate). After passing through phase retarder 224 (e.g., a quarter-wave plate), the circularly polarized light changes its polarization state and is converted into linearly polarized light (referred to as S light).

[0166] Polarized reflection: The linearly polarized light converted to S light then propagates to the polarizing reflective element 223. This polarizing reflective element 223 selectively reflects the S light while allowing light with other polarization directions (such as P light) to pass through. Therefore, the S light is reflected by the polarizing reflective element 223 back to the lens assembly.

[0167] Passing through the phase retarder 224 twice: the reflected S light passes through the phase retarder 224 (such as a quarter wave plate) on the second surface 22 again, and its polarization state changes again, from S light to circularly polarized light.

[0168] Partial Reflection: The converted circularly polarized light then propagates to the first surface 21 of the lens assembly, which is provided with a beam splitter 211 (e.g., a semi-transparent, semi-reflective film). This beam splitter 211 allows some light to pass through while reflecting some. In this optical path, the circularly polarized light is partially reflected back into the lens assembly by beam splitter 211.

[0169] Passing through the phase retarder 224 three times: the circularly polarized light reflected back passes through the phase retarder 224 (such as a quarter wave plate) on the second surface 22 again, and its polarization state is converted from circular polarization to another linear polarization light (denoted as P light).

[0170] Final transmission: The linearly polarized light converted into P light then passes through the lens group, is no longer reflected or deflected by subsequent components, and directly enters the human eye 01, completing the entire optical path propagation process.

[0171] The infrared light emitted by the light source 6 passes through the edge area of the first lens 2 and enters the human eye 01 , and is reflected by the human eye 01 to the camera 7 .

[0172] The optical module provided in the embodiment of the present application may have a field of view (FOV) between 90° and 120°.

[0173] According to another embodiment of the present application, a near-eye display device is provided, comprising a housing and the optical module as described above, wherein the optical module is disposed in the housing.

[0174] The near-eye display device provided in the embodiment of the present application is, for example, a VR head-mounted display device.

[0175] The specific implementation of the near-eye display device of the embodiment of the present application can refer to the various embodiments of the above-mentioned AR optical module, and therefore at least has all the beneficial effects brought by the technical solutions of the above-mentioned embodiments, which will not be repeated here one by one.

[0176] The optical module of the present application is described below through Examples 1 to 3.

[0177] Example 1

[0178] The optical module provided in this embodiment 1 is shown in FIG. Figure 1 , comprising a display screen 1, a folded optical path component and an eye tracking component; wherein the display screen 1 is used to provide light for imaging display, and a protective glass is provided on the light-emitting surface of the display screen 1;

[0179] The folded optical path component is arranged on the light-emitting side of the display screen 1, and is used to guide the light emitted by the display screen 1 to the human eye 01. The folded optical path component includes a first lens 2, a beam splitter 211, a phase retarder 224, a polarized reflection element 223, a polarizing element 222 and an anti-reflection film 221; wherein the beam splitter 211 is arranged on the first surface 21 of the first lens 2, see Figure 4 The anti-reflection film 221, the polarizing element 222, the polarized reflective element 223 and the phase retarder 224 form a composite film material, and the composite film material is disposed on the second surface 22 of the first lens 2;

[0180] The eye tracking component, see Figure 2 , including a light source 6 and a camera 7, a plurality of light sources 6 are arranged in a ring at the edge area of the first lens 2 away from the human eye side, the camera 7 is arranged on the outside of the display screen 1, and the camera 7 is configured to receive infrared light emitted from the light source 6 and reflected by the human eye 01.

[0181] The FOV of the optical module provided in this embodiment 1 is 95°.

[0182] Some optical parameters of the optical module provided in this embodiment 1 are shown in Table 1 below.

[0183] Table 1

[0184]

[0185] The optical module provided in this embodiment 1 has optical performance such as Figures 5 to 8 As shown: Figure 5 is a point diagram diagram. Figure 6 is the MTF curve graph, Figure 7 It is the field curvature and distortion diagram, Figure 8 This is a diagram of vertical chromatic aberration.

[0186] A spot diagram is a diffuse pattern formed by the intersection of many light rays emitted from a point and the image plane after passing through the optical module. Due to aberration, the intersection points of the light rays with the image plane are no longer concentrated at the same point, but are spread over a certain range. It is used to evaluate the imaging quality of the projection optical module. Figure 5 In the optical module provided by the first embodiment, the maximum value of the image point in the point diagram is less than 38 μm.

[0187] The MTF curve is a modulation transfer function graph that represents the imaging clarity of an optical module through the contrast between black and white line pairs. Figure 6 The optical module provided in this embodiment 1 has an MTF greater than 0.1 at 10lp / mm.

[0188] See also Figure 7In the optical module provided in this embodiment 1, the maximum distortion occurs in 1 field of view, and the absolute value is less than 45%.

[0189] Vertical axial chromatic aberration is also called chromatic aberration of magnification. It mainly refers to the difference in the focal position of blue light and red light on the image plane when a complex main light on the object side is transformed into multiple light rays due to the dispersion of the refraction system. Figure 8 The optical module provided in this embodiment 1 has a maximum color difference value of less than 40 μm.

[0190] Example 2

[0191] The optical module provided in this embodiment 2 is shown in FIG. Figure 9 , comprising a display screen 1, a folded optical path component and an eye tracking component; wherein the display screen 1 is used to provide light for imaging display, and a protective glass is provided on the light-emitting surface of the display screen 1;

[0192] The folded optical path component is arranged on the light-emitting side of the display screen 1, and is used to guide the light emitted by the display screen 1 to the human eye 01. The folded optical path component includes a first lens 2, a second lens 3 and a third lens 4, as well as a beam splitter 211, a phase retarder 224, a polarized reflection element 223, a polarizing element 222 and an anti-reflection film 221; wherein the beam splitter 211 is arranged on the first surface 21 of the first lens 2, see Figure 4 The anti-reflection film 221, the polarizing element 222, the polarized reflective element 223 and the phase retarder 224 form a composite film material, and the composite film material is disposed on the second surface 22 of the first lens 2;

[0193] The eye tracking component, see Figure 10 , including a light source 6 and a camera 7, a plurality of light sources 6 are arranged in a ring at the edge area of the first lens 2 away from the human eye side, the camera 7 is arranged on the outside of the display screen 1, and the camera 7 is configured to receive infrared light emitted from the light source 6 and reflected by the human eye 01.

[0194] The FOV of the optical module provided in this embodiment 2 is 115°.

[0195] Some optical parameters of the optical module provided in this embodiment 2 are shown in Table 2 below.

[0196] Table 2

[0197]

[0198] The optical module provided in this embodiment 2 has optical performance such as Figures 11 to 14 As shown: Figure 11 is a point diagram diagram. Figure 12 is the MTF curve graph, Figure 13 It is the field curvature and distortion diagram, Figure 14 This is a diagram of vertical chromatic aberration.

[0199] See also Figure 11 In the optical module provided by the second embodiment, the maximum value of the image point in the point diagram is less than 37 μm.

[0200] See also Figure 12 The optical module provided in this embodiment 2 has an MTF greater than 0.75 at 10 lp / mm.

[0201] See also Figure 13 In the optical module provided in this embodiment 2, the maximum distortion occurs in 1 field of view, and the absolute value is less than 45%.

[0202] See also Figure 14 The optical module provided in this embodiment 2 has a maximum color difference value of less than 40 μm.

[0203] Example 3

[0204] The optical module provided in this embodiment 3 is shown in FIG. Figure 15 , comprising a display screen 1, a folded optical path component, a fourth lens 5, a second lens 3, a third lens 4 and an eye tracking component; wherein the display screen 1 is used to provide light for imaging display, and a protective glass is provided on the light-emitting surface of the display screen 1;

[0205] The folded optical path component is arranged on the light-emitting side of the display screen 1, and is used to guide the light emitted by the display screen 1 to the human eye 01. The folded optical path component includes a first lens 2, a beam splitter 211, a phase retarder 224, a polarized reflection element 223, a polarizing element 222 and an anti-reflection film 221; wherein the beam splitter 211 is arranged on the first surface 21 of the first lens 2, see Figure 4 The anti-reflection film 221, the polarizing element 222, the polarized reflective element 223, and the phase retarder 224 form a composite film material, which is disposed on the second surface 22 of the first lens 2; and the first lens 2 and the fourth lens 5 are glued together to form a glued lens group;

[0206] The eye tracking component, see Figure 16 , including a light source 6 and a camera 7, a plurality of the light sources 6 are arranged in a ring between the edge area of the second lens 3 and the third lens 4, the camera 7 is arranged on the outside of the display screen 1, and the camera 7 is configured to receive infrared light emitted from the light source 6 and reflected by the human eye 01.

[0207] The FOV of the optical module provided in this embodiment 3 is 100°.

[0208] Some optical parameters of the optical module provided in this embodiment 3 are shown in Table 3 below.

[0209] Table 3

[0210]

[0211] The optical module provided in this embodiment 3 has optical performance such as Figures 17 to 20 As shown: Figure 17 is a point diagram diagram. Figure 18 is the MTF curve graph, Figure 19 It is the field curvature and distortion diagram, Figure 20 This is a diagram of vertical chromatic aberration.

[0212] See also Figure 17 In the optical module provided by the third embodiment, the maximum value of the image point in the point diagram is less than 10 μm.

[0213] See also Figure 18 The optical module provided in this embodiment 3 has an MTF of >0.85 at 10lp / mm.

[0214] See also Figure 19 In the optical module provided in this embodiment 3, the maximum distortion occurs in 1 field of view, and the absolute value is less than 45%.

[0215] See also Figure 20 The optical module provided in this embodiment 3 has a maximum color difference value of less than 40 μm.

[0216] The relationship between the lens curvature of the light source 6 and the human eye 01 in the above-mentioned embodiments 1 to 3 is shown in Table 4 below.

[0217] Table 4

[0218]

[0219] The above embodiments focus on the differences between the various embodiments. As long as the different optimization features between the various embodiments are not contradictory, they can be combined to form a better embodiment. Considering the simplicity of the text, they will not be repeated here.

[0220] Although some specific embodiments of the present application have been described in detail by way of example, it should be understood by those skilled in the art that the above examples are for illustration only and are not intended to limit the scope of the present application. It should be understood by those skilled in the art that the above examples may be modified without departing from the scope and spirit of the present application. The scope of the present application is defined by the appended claims.

Claims

1. An optical module, characterized in that: include: Display screen (1); a folded optical path component, arranged on the light-emitting side of the display screen (1), for guiding light emitted by the display screen (1) to a human eye (01), the folded optical path component comprising at least one lens; An eye tracking component comprises a light source (6) and a camera (7), wherein the light source (6) is arranged on a side of the edge area of the folded optical path component close to the display screen (1), and the lens between the light source (6) and the human eye (01) must meet the following requirements: |min[1 / ]|≥5, wherein n is the number of lenses between the light source (6) and the human eye (01), Ai is the curvature value of the i-th lens on the side surface close to the human eye within the range of 0.7 to 1 normalized aperture, and Bi is the curvature value of the i-th lens on the side surface away from the human eye within the range of 0.7 to 1 normalized aperture.

2. The optical module according to claim 1, wherein: The folded optical path assembly comprises a first lens (2); The optical module comprises a second lens (3) and a third lens (4), and the second lens (3) and the third lens (4) are sequentially arranged between the first lens (2) and the display screen (1), and all the lenses and the display screen (1) are arranged along the same optical axis.

3. The optical module according to claim 2, wherein: The light sources (6) are multiple and distributed in a ring shape on the edge area of the first lens (2) close to the display screen (1), and the lens between the light source (6) and the human eye (01) satisfies: |min[1 / (A1-B1)]|≥5, wherein A1 is the curvature value of the surface of the first lens (2) close to the human eye within the range of 0.7 to 1 aperture, and B1 is the curvature value of the surface of the first lens (2) away from the human eye within the range of 0.7 to 1 aperture.

4. The optical module according to claim 3, wherein: The lens between the light source (6) and the human eye (01) also satisfies: |min[1 / (A1-B1)]|≤20.

5. The optical module according to claim 1, wherein: The folded optical path assembly comprises a first lens (2); The optical module comprises a second lens (3), a third lens (4) and a fourth lens (5), wherein the fourth lens (5), the second lens (3) and the third lens (4) are sequentially arranged between the first lens (2) and the display screen (1), and all the lenses and the display screen (1) are arranged along the same optical axis.

6. The optical module according to claim 5, wherein: The light source (6) is located in the edge area of the second lens (3) on the side close to the display screen (1), and satisfies the following relationship: |min[1 / (A1-B1+A2-B2)]|≥5, wherein A1 is the curvature value of the surface of the first lens (2) close to the human eye within the range of 0.7 to 1 aperture, B1 is the curvature value of the surface of the first lens (2) away from the human eye within the range of 0.7 to 1 aperture, A2 is the curvature value of the surface of the fourth lens (5) close to the human eye within the range of 0.7 to 1 aperture, and B2 is the curvature value of the surface of the fourth lens (5) away from the human eye within the range of 0.7 to 1 aperture.

7. The optical module according to claim 5 or 6, characterized in that: The first lens (2) and the fourth lens (5) are glued together to form a glued lens group.

8. The optical module according to claim 6, wherein: The lens between the light source (6) and the human eye (01) also satisfies: |min[1 / (A1-B1+A2-B2)]|≤20.

9. The optical module according to claim 2 or 5, characterized in that: The folded optical path component further includes a light splitting element (211), a phase retarder (224), and a polarized reflection element (223); The light splitting element (211) is arranged on the surface of the first lens (2) on the side close to the display screen (1), and the phase delay device (224) and the polarization reflection element (223) are arranged in sequence on the surface of the first lens (2) on the side away from the display screen (1).

10. The optical module according to claim 9, wherein: The folded optical path component further comprises a polarizing element (222), wherein the polarizing element (222) is arranged on a surface of the polarizing reflection element (223) facing away from the phase retarder (224); The phase retarder (224), the polarized reflection element (223), and the polarizing element (222) form a composite film material.

11. The optical module according to claim 1, wherein: The light-emitting surface of the display screen (1) is provided with protective glass, and the total thickness of the protective glass is ≥0.5 mm.

12. The optical module according to claim 1, wherein: The camera (7) is arranged outside the display screen (1), and the camera (7) is configured to receive infrared light emitted from the light source (6) and reflected by the human eye (01).

13. A near-eye display device, characterized in that: include: shell; and The optical module according to any one of claims 1 to 12.

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