Optical module and near-to-eye display equipment

Abstract

The embodiment of the invention provides an optical module and near-to-eye display equipment. The optical module is used for XR optical equipment and comprises a cemented prism, a first lens and a second lens, and the first lens is located between the cemented prism and the second lens; the glued prism comprises a first prism, a second prism and a polarization reflection element glued between the first prism and the second prism. The first lens comprises a fourth surface and a fifth surface, and the fourth surface and the second prism are adjacent to each other and are arranged at an interval; the second lens comprises a sixth surface and a seventh surface, the seventh surface deviates from the first lens, and the seventh surface is a partial reflection surface; a phase delayer is arranged on the fourth surface or the sixth surface; the optical module meets the condition that EFL15 / EFL is larger than or equal to 1.9 and smaller than or equal to 5.4, EFL15 is the total effective focal length of the cemented prism and the first lens, and EFL is the effective focal length of the optical module.

Description

Technical Field

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

[0002] With the rise of the concept of the metaverse, XR technology has developed rapidly, covering VR technology, AR technology, and MR technology. As the core component of XR technology, the performance of the near-eye display system directly affects the user experience.

[0003] However, existing near-eye display devices still have some problems in the design of optical modules, such as large size, poor imaging quality, and limited field of view. Therefore, how to design an optical module with small size, high imaging quality, and large field of view has become a technical problem that needs to be solved urgently. Summary of the invention

[0004] The purpose of this application is to provide a new technical solution for an optical module and a near-eye display device.

[0005] In a first aspect, the present application provides an optical module. The optical module is used for an XR optical device, and the optical module includes a cemented prism, a first lens, and a second lens, wherein the first lens is located between the cemented prism and the second lens;

[0006] The glued prism includes a first prism, a second prism and a polarized reflection element glued between the two prisms;

[0007] The first lens includes a fourth surface and a fifth surface, and the fourth surface is adjacent to and spaced from the second prism;

[0008] The second lens includes a sixth surface and a seventh surface, the seventh surface is away from the first lens, and the seventh surface is a partial reflection surface;

[0009] A phase retarder is arranged on the fourth surface or the sixth surface;

[0010] The optical module meets the following conditions: 1.9≤EFL 15 / EFL≤5.4; where EFL 15 is the total effective focal length of the cemented prism and the first lens, and EFL is the effective focal length of the optical module.

[0011] Optionally, the optical module satisfies: 1.5≤EFL 67 / EFL≤51.4; where EFL 67 It is the effective focal length of the light incident from the sixth surface, reflected by the seventh surface, and then emitted from the sixth surface.

[0012] Optionally, the optical module satisfies: 1.78≤EFL 67 / EFL≤7.32.

[0013] Optionally, the optical module satisfies: 0≤EFL 45 / EFL 67 ≤3.6; among which, EFL 45 is the effective focal length of light incident from the fourth surface and emitted from the fifth surface.

[0014] Optionally, a curvature of the fifth surface is CV5, a curvature of the seventh surface is CV7, and 1.5≤CV5 / CV7≤4.

[0015] Optionally, a curvature of the sixth surface is CV6, a curvature of the seventh surface is CV7, and 0≤CV6 / CV7≤2.9.

[0016] Optionally, the first prism includes a first surface and a second surface, wherein the second surface is a bonding surface where the first prism and the second prism are bonded to each other, and the polarized reflection element is disposed on the second surface;

[0017] The curvature of the first surface is CV1, the curvature of the seventh surface is CV7, and 0≤|CV1 / CV7|≤0.4.

[0018] Optionally, the first surface is a curved surface or a plane, and the second surface is a plane.

[0019] Optionally, an angle θ1 formed between the second surface and the vertical direction is an acute angle.

[0020] Optionally, the second prism further includes a third surface and an eighth surface;

[0021] An air gap is provided between the third surface and the fourth surface, and the third surface is a plane;

[0022] The eighth surface is the top surface of the second prism, and an angle θ2 formed by the optical axis of the eighth surface and the horizontal direction is an acute angle.

[0023] Optionally, the optical module further includes a display screen, and the display screen is arranged on one side of the eighth surface.

[0024] Optionally, the fourth surface is a plane, and the fifth surface is a curved surface.

[0025] Optionally, the sixth surface is a plane, and the seventh surface is a plane or a curved surface.

[0026] Optionally, the optical module includes at most 4 curved surfaces.

[0027] Optionally, the centers of the first surface, the fifth surface, the sixth surface and the seventh surface are all located on the same optical axis, and the positive direction of the vector height of the first surface, the fifth surface, the sixth surface and the seventh surface is the direction away from the human eye along the optical axis.

[0028] Optionally, the chief ray of the 0 degree field of view coincides with the optical axes of the fifth surface, the sixth surface, the seventh surface and the eighth surface.

[0029] In a second aspect, the present application provides a near-eye display device, wherein the near-eye display device comprises the optical module as described in the first aspect.

[0030] The beneficial effects of this application are:

[0031] An embodiment of the present application provides an optical module, which is mainly used in near-eye display devices, particularly in the field of XR / AR (mixed reality / augmented display) technology. Through optical parameter design and optical component combination, it achieves improved imaging quality while maintaining a small volume.

[0032] 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

[0033] The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the specification and, together with the description, serve to explain the principles of the specification.

[0034] Figure 1 One of the structural schematic diagrams of the optical module provided in the embodiment of the present application;

[0035] Figure 2 The second structural diagram of the optical module provided in the embodiment of the present application;

[0036] Figure 3 for Figure 2 MTF diagram of the optical module shown;

[0037] Figure 4 The third structural diagram of the optical module provided in the embodiment of the present application;

[0038] Figure 5 for Figure 4 MTF diagram of the optical module shown;

[0039] Figure 6 A fourth structural diagram of an optical module provided in an embodiment of the present application;

[0040] Figure 7 for Figure 6MTF diagram of the optical module shown;

[0041] Figure 8 A fifth structural diagram of an optical module provided in an embodiment of the present application;

[0042] Fig. 9 for Figure 8 MTF diagram of the optical module shown;

[0043] Fig.10 The sixth structural diagram of the optical module provided in the embodiment of the present application;

[0044] Fig.11 for Fig.10 MTF diagram of the optical module shown;

[0045] Fig.12 The seventh structural diagram of the optical module provided in the embodiment of the present application;

[0046] Fig.13 for Fig.12 MTF diagram of the optical module is shown.

[0047] Description of reference numerals:

[0048] 1. First prism; 2. Second prism; 3. First lens; 4. Second lens; 5. Beam splitter; 6. Phase retarder; 7. Polarization reflective element; 8. Display screen; 9. Protective glass;

[0049] S0, human eye; S1, first surface; S2, second surface; S3, third surface; S4, fourth surface; S5, fifth surface; S6, sixth surface; S7, seventh surface. DETAILED DESCRIPTION

[0050] 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 arrangement of components and steps, numerical expressions and numerical values ​​set forth in these embodiments do not limit the scope of the present application.

[0051] The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way intended to limit the present application, its application, or uses.

[0052] 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.

[0053] In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limiting. Therefore, other examples of the exemplary embodiments may have different values.

[0054] It should be noted that like reference numerals and letters refer to similar items in the following figures, and therefore, once an item is defined in one figure, it need not be further discussed in subsequent figures.

[0055] The optical module and near-eye display device provided in the embodiments of the present application are described in detail below in conjunction with the accompanying drawings.

[0056] According to one embodiment of the present application, an optical module is provided. Figure 1 The optical module includes a cemented prism, a first lens 3 and a second lens 4, and the first lens 3 is located between the cemented prism and the second lens 4; the cemented prism includes a first prism 1, a second prism 2 and a polarized reflection element 7 cemented between the two prisms; the first lens 3 includes a fourth surface S4 and a fifth surface S5, and the fourth surface S4 and the second prism 2 are adjacent and spaced apart; the second lens 4 includes a sixth surface S6 and a seventh surface S7, and the seventh surface S7 is away from the first lens 3, and the seventh surface S7 is a partial reflection surface; a phase retarder 6 is arranged on the fourth surface S4 or the sixth surface S6; the optical module satisfies: 1.9≤EFL 15 / EFL≤5.4; where EFL 15 is the total effective focal length of the cemented prism and the first lens 3, and EFL is the effective focal length of the optical module.

[0057] The optical module provided in the embodiment of the present application is mainly used in near-eye display devices, and is particularly suitable for the field of XR (mixed reality or augmented display) technology, where XR technology covers VR technology, AR technology, MR technology, etc.

[0058] The optical module provided in the embodiment of the present application includes a glued prism, which is mainly composed of a first prism 1, a second prism 2 and a polarized reflective element 7 glued therebetween. These three optical elements are tightly glued together to form an integral optical element.

[0059] The polarized reflection element 7 is used to realize polarized reflection of light. Specifically, the polarized reflection element 7 can ensure that the light is reflected when it first arrives, and is transmitted when it arrives again after passing through the phase retarder 6 (such as a quarter wave plate) twice.

[0060] The polarized reflective element 7 is a key component in the optical module, and it works together with other optical elements such as two prisms, two lenses and a phase retarder 6. The synergy of these optical elements enables the module to maintain a small volume at a large field of view and maintain good imaging quality.

[0061] The optical module of the embodiment of the present application further includes two lenses, namely a first lens 3 and a second lens 4 ; wherein the first lens 3 is disposed adjacent to the cemented prism, and the second lens 4 is disposed adjacent to the first lens 3 .

[0062] Regarding the first lens 3, specifically:

[0063] See also Figure 1 The first lens 3 includes a fourth surface S4 and a fifth surface S5, which together determine the optical performance of the first lens 3. The main function of the first lens 3 is to focus the light from the cemented prism to ensure that the light can continue to be projected to the second lens 4.

[0064] Regarding the second lens 4, specifically:

[0065] Please continue to see Figure 1 The second lens 4 has a sixth surface S6 and a seventh surface S7, and the sixth surface S6 is adjacent to the fifth surface S5 of the first lens 3, and the seventh surface S7 is a partial reflection surface. The partial reflection characteristic of the seventh surface S7 allows part of the light to pass through and reflects part of the light at the same time. For example, a semi-transparent and semi-reflective film can be provided on the seventh surface S7 so that the seventh surface S7 has the characteristics of partial reflection and transmission at the same time.

[0066] The optical module of the present application further includes a phase retarder 6 , which is disposed on the fourth surface S4 or the sixth surface S6 , which means that it is located on the front surface of the first lens 3 or the front surface of the second lens 4 .

[0067] The phase retarder 6 is, for example, a quarter wave plate (QWP), which can be used to change the polarization state of light. In the present application, the phase retarder 6 works together with the polarization reflection element 7 to achieve polarization reflection and transmission of light. When the light first reaches the polarization reflection element 7, it is reflected. The light then passes through the phase retarder 6 twice, and its polarization state changes. When it reaches the polarization reflection element 7 for the second time, due to the change in polarization state, the light is transmitted instead of being reflected again.

[0068] By controlling the polarization state of light, the phase retarder 6 helps to achieve the correct folding and transmission of light in the optical module, which is crucial for maintaining the imaging quality of the optical module, reducing stray light and ensuring that users can see clear, undistorted images.

[0069] In the present application, the phase retarder 6 is designed to be directly disposed on the fourth surface S4 or the sixth surface S6. This arrangement makes the optical module compact and stable, and can achieve a large field of view and good imaging quality while maintaining a small volume.

[0070] In the optical module provided in the embodiment of the present application, EFL is also described. 15 The ratio between (the total effective focal length of the cemented prism and the first lens 3) and EFL (the effective focal length of the optical module of the present application), that is, 1.9≤EFL 15 / EFL≤5.4. This effective focal length ratio is crucial to ensure that the optical module has excellent optical performance.

[0071] Specifically, 1.9 ≤ EFL 15 / EFL≤5.4 describes the ratio of the cemented prism and the first lens 3 combination (EFL 15 ) relative to the focusing capability of the entire optical module (EFL). By controlling this ratio, a larger field of view can be achieved while maintaining a smaller volume of the optical module, thereby improving the user's immersion and comfort. In addition, this ratio helps to ensure that the light can maintain good convergence performance after passing through the prism and the first lens 3, thereby forming a clear, distortion-free image at the human eye S0.

[0072] According to the 1.9≤EFL described in this application 15 / EFL≤5.4, EFL 15 The lower limit of / EFL is 1.9, which ensures that EFL 15 will not be much smaller than EFL, thus avoiding over-focusing of the light after passing through the cemented prism and the first lens 3. The upper limit of this ratio is 5.4, which limits EFL 15 It is not much larger than the EFL, which prevents the light from diverging too much after passing through these components.

[0073] The appropriate effective focal length ratio range provided in this application helps maintain the imaging quality of the optical module in the entire field of view. If this ratio is too small, the image in the center field of view may be too clear while the image in the edge field of view may be distorted. If the ratio is too large, the image in the entire field of view may appear blurred.

[0074] In summary, the effective focal length ratio shown in the embodiment of the present application is 1.9≤EFL 15 / EFL≤5.4 is an important optical parameter when designing an optical module. By precisely controlling this ratio, it is possible to ensure that the optical module provides high-quality imaging while maintaining a small size.

[0075] Furthermore, 2.21≤EFL15 / EFL≤4.34. By setting EFL 15 The ratio of / EFL is controlled within this preferred range to ensure that the light can maintain good convergence performance and reduce aberration and distortion after passing through the cemented prism and the first lens 3. This helps to form a clear, distortion-free image at the human eye and enhance the user's visual experience. This range achieves a larger field of view while maintaining a smaller volume of the optical module, which can enhance the user's sense of immersion. The smaller volume helps to achieve lightweight and miniaturization of near-eye display devices and improve wearing comfort.

[0076] Optimized EFL 15 The / EFL range helps reduce light loss during transmission and improves light energy utilization, which means more light can reach the human eye and enhance the brightness of the image.

[0077] In summary, 2.21≤EFL 15 The design of / EFL≤4.34 plays a vital role in the design of optical modules. It not only optimizes the imaging quality, but also balances the field of view and volume, improves the utilization of light energy, and ultimately enhances the user experience.

[0078] An embodiment of the present application provides an optical module, which is mainly used in near-eye display devices, particularly in the field of XR (mixed reality or augmented display) technology. Through optical parameter design and optical component combination, it is possible to improve imaging quality while maintaining a small volume.

[0079] In some examples of the present application, the optical module satisfies: 1.5≤EFL 67 / EFL≤51.4; where EFL 67 It is the effective focal length of the light incident from the sixth surface S6, reflected from the seventh surface S7, and then emitted from the sixth surface S6.

[0080] Among them, EFL 67 is the effective focal length of the light incident from the sixth surface S6 of the second lens 4, reflected from the seventh surface S7, and then emitted from the sixth surface S6 (the light is folded in the second lens 4). This light transmission also involves the special design of one surface of the second lens 4, that is, the seventh surface S7 is designed as a partial reflection surface.

[0081] The optical module provided in the present application includes a cemented prism (the cemented prism is formed by cementing a first prism 1 and a second prism 2 and includes a polarized reflective element 7), a first lens 3 and a second lens 4. The first lens 3 is located between the cemented prism and the second lens 4, and the sixth surface S6 and the seventh surface S7 are respectively the front and rear surfaces of the second lens 4, see Figure 1 .

[0082] The analysis of the effective focal length ratio proposed in this example of the present application is as follows:

[0083] EFL 67 The ratio / EFL reflects the relative relationship between the focusing ability of the light passing through a specific path (sixth surface S6 → seventh surface S7 → sixth surface S6) inside the second lens 4 and the focusing ability of the entire optical module. From the range of the ratio in this example of the present application:

[0084] When EFL 67 When / EFL is close to or greater than 1.5, it means that the second lens 4 plays a relatively important role in the optical module. In particular, when realizing the superposition display of physical perspective and virtual images, the second lens 4 can effectively adjust the path and focusing performance of light to ensure that the user can see clear virtual images and perceive the external environment. This lower limit ensures that the entire optical module will not cause image distortion or limited field of view due to the excessive effect of the second lens 4 while providing sufficient field of view and imaging quality.

[0085] When EFL 67 When / EFL is close to or greater than 5.14, the upper limit is set to prevent the second lens 4 from having too strong a refraction and reflection effect on light, thereby destroying the overall imaging effect of the optical module. By setting this upper limit, it is possible to ensure that the optical module achieves good imaging quality and user experience while maintaining a small size and weight.

[0086] According to this example of the present application, by precisely controlling the EFL 67 The ratio range of / EFL can optimize the imaging quality of the optical module under different fields of view. This helps to reduce image distortion and improve image clarity, thereby providing a better visual experience.

[0087] In augmented reality (AR) applications, by properly designing EFL 67 The ratio of / EFL can ensure that the optical module provided in the present application can accurately superimpose the virtual image onto the real-world view, thereby providing a realistic and natural augmented reality experience.

[0088] According to the ratio of effective focal lengths provided in this example of the present application, while maintaining high-quality imaging, it also helps to achieve a compact design of the optical module. This is particularly important for near-eye display devices that require high integration, such as smart glasses.

[0089] In some examples of the present application, the optical module satisfies: 1.78≤EFL 67 / EFL≤7.32.

[0090] By incorporating EFL 67 The control of / EFL within this range of the example of the present application can ensure that the light can still maintain good focusing ability after passing through a specific reflection and refraction path inside the second lens 4. This helps to reduce the loss and distortion of light during transmission and improve the imaging quality.

[0091] For example, in augmented reality (AR) or mixed reality (MR) applications, the optical module needs to process both virtual images and real-world light. The design of this range of examples in this application helps ensure that virtual images can be accurately superimposed on real-world views while maintaining clarity and contrast between the two, thereby enhancing the user's sense of immersion and reality.

[0092] In addition, this ratio range in this example of the present application can ensure that the imaging quality does not decrease significantly while maintaining a larger field of view, thereby meeting the user's demand for high-quality visual experience.

[0093] In some examples of the present application, the optical module satisfies: 0≤EFL 45 / EFL 67 ≤3.6; among which, EFL 45 It is the effective focal length of the light incident from the fourth surface S4 and emitted from the fifth surface S5.

[0094] EFL 45 It refers to the effective focal length of the light incident from the fourth surface S4 of the first lens 3 and emitted from the fifth surface S5 thereof, that is, it refers to the effective focal length of the first lens 3. Therefore, it involves the optical design of the first lens 3, especially the surface shape and material selection of the fourth surface S4 and the fifth surface S5 thereof.

[0095] EFL 67 It refers to the effective focal length of light incident from the sixth surface S6 of the second lens 4, reflected by the seventh surface S7, and then emitted from the sixth surface S6. This reflects the optical design of the second lens 4. The seventh surface S7 is a partial reflection surface, allowing light to be reflected inside the second lens 4.

[0096] The optical module comprises a cemented prism (composed of a first prism 1 and a second prism 2, with a polarized reflective element 7 sandwiched therebetween), a first lens 3 and a second lens 4. These components work together to achieve transmission, polarization and focusing of light.

[0097] Regarding the effective focal length ratio mentioned in this example of this application:

[0098] EFL 45 / EFL 67This ratio reflects the relative relationship between the focusing capabilities of light passing through different paths inside the first lens 3 (fourth surface S4→fifth surface S5) and inside the second lens 4 (sixth surface S6→seventh surface S7→sixth surface S6).

[0099] When EFL 45 / EFL 67 When it is close to 0, it means EFL 45 Relative to EFL 67 The first lens 3 is very small, that is, the refraction effect of the first lens 3 on the light is relatively weak in the entire optical module. This may be because the first lens 3 mainly plays the role of adjusting the direction of the light, rather than strongly focusing the light.

[0100] The upper limit is set to ensure that the refractive effect of the first lens 3 is not too strong, thereby avoiding adverse effects on the overall imaging effect of the optical module. 45 / EFL 67 If the value exceeds 3.6, the first lens 3 may refract the light excessively, resulting in virtual image distortion or limited field of view. By setting this upper limit, the interaction between the first lens 3 and the second lens 4 can be kept within a reasonable range, thereby achieving good imaging quality and user experience.

[0101] According to the ratio range of effective focal length provided in this example of the present application, by reasonably controlling EFL 45 With EFL 67 The ratio relationship between them can ensure that the light can maintain good convergence performance after passing through the first lens 3 and the second lens 4, so as to form a clear and distortion-free image at the human eye S0. In addition, while ensuring the imaging quality, by adjusting the refraction and reflection effects of the first lens 3 and the second lens 4, the physical perspective effect can be enhanced, so that the user can more naturally perceive the superposition display of the external environment and the virtual image.

[0102] Excellent optical performance and clear imaging quality can enhance users' immersion and comfort in application scenarios such as XR / AR.

[0103] Furthermore, the optical module satisfies: 0.302≤EFL 45 / EFL 67 ≤2.52. By setting EFL 45 / EFL 67 By controlling within this range, the transmission path of light inside the optical module can be optimized. An appropriate ratio can ensure that light can be transmitted along the expected path when passing through the first lens 3 and the second lens 4, reducing unnecessary refraction and reflection, thereby improving imaging quality.

[0104] EFL 45 It mainly affects the imaging quality of the optical module in the central field of view, while EFL 67 It is closely related to the light transmission and imaging within the entire field of view. 45 / EFL 67 The ratio is set between 0.302 and 2.52, which can ensure that the imaging quality of the central field of view will not be significantly reduced while maintaining a larger field of view angle, thus achieving a good balance between the field of view angle and imaging quality.

[0105] For near-eye display devices, image quality and field of view are key factors that directly affect user experience. 45 / EFL 67 The ratio can provide high-quality imaging effects while ensuring a larger field of view, thereby enhancing the user's immersion and comfort.

[0106] In some examples of the present application, a curvature of the fifth surface S5 is CV5, a curvature of the seventh surface S7 is CV7, and 1.5≤CV5 / CV7≤4.

[0107] Wherein, CV5 represents the curvature of the fifth surface S5 of the first lens 3, and CV7 represents the curvature of the seventh surface S7 of the second lens 4. It should be noted that curvature is an important parameter to describe the curvature of the lens surface, which directly affects the focusing and imaging characteristics of light.

[0108] The ratio CV5 / CV7 reflects the relative relationship in curvature between the fifth surface S5 of the first lens 3 and the seventh surface S7 of the second lens 4. This effective focal length ratio range is crucial for controlling the focus, polarization and transmission path of light.

[0109] When CV5 / CV7 is close to or greater than 1.5, it means that the curvature of the fifth surface S5 is larger than the curvature of the seventh surface S7. This means that the fifth surface S5 has a stronger refraction effect on light, which helps to guide the light more accurately to the human eye, thereby improving the imaging quality. When designing an optical module, a larger curvature of the fifth surface S5 can compensate for the aberrations of other optical elements, making the imaging performance of the entire system more excellent.

[0110] The upper limit is set to avoid the curvature of the fifth surface S5 being too large, thereby causing excessive refraction or distortion of light when passing through the fifth surface S5. If CV5 / CV7 exceeds 4, the fifth surface S5 will have an adverse effect on the light and reduce the imaging quality. By setting this upper limit, it can be ensured that the curvature relationship between the fifth surface S5 and the sixth surface S7 is kept within a reasonable range, thereby achieving good imaging effects and user experience.

[0111] According to the effective focal length ratio provided in this example of the present application, it is beneficial to optimize the imaging quality. Specifically, by accurately controlling the ratio range of CV5 / CV7, the imaging quality of the optical module under different fields of view and lighting conditions can be optimized. This helps to reduce image distortion and improve image clarity, thereby providing a better visual experience.

[0112] Further, the optical module satisfies: 1.89≤CV5 / CV7≤3.67. By controlling the ratio of the curvature CV5 of the fifth surface S5 of the first lens 3 to the curvature CV7 of the seventh surface S7 of the second lens 4 within this range, the imaging quality of the optical module can be effectively optimized. The appropriate curvature ratio helps to reduce the aberration and distortion of light during transmission, making the imaging clearer and more accurate. In addition, by adjusting the ratio of CV5 and CV7, the curvature combination that best suits the current application scenario can be found within this range, thereby meeting diverse needs.

[0113] In some examples of the present application, the curvature of the sixth surface S6 is CV6, the curvature of the seventh surface S7 is CV7, and 0≤CV6 / CV7≤2.9.

[0114] The ratio CV6 / CV7 reflects the relative relationship in curvature between the two surfaces of the second lens 4, ie, the sixth surface S6 and the seventh surface S7.

[0115] When CV6 / CV7 is close to 0, it means that the curvature of the sixth surface S6 is very small relative to the curvature of the seventh surface S7, and may even be close to a plane. This design may be used to reduce the refraction of the sixth surface S6 on light, so that it relies more on the reflection of S7 to achieve light guidance and imaging. In some application scenarios, such as when it is necessary to emphasize the physical perspective effect, a smaller curvature design of the sixth surface S6 is more advantageous because it can reduce interference with the virtual image while maintaining a better perception of the external environment.

[0116] The upper limit is set to avoid the curvature of the sixth surface S6 being too large, thereby causing excessive refraction or distortion of light when passing through the sixth surface S6. If CV6 / CV7 exceeds 2.9, the sixth surface S6 may have an adverse effect on the light, reduce the imaging quality or interfere with the physical perspective effect. By setting this upper limit, it can be ensured that the curvature relationship between the sixth surface S6 and the seventh surface S7 is maintained within a reasonable range, thereby achieving good imaging effects and user experience.

[0117] It should be noted that, according to the above two examples, 1.5≤CV5 / CV7≤4, this ratio range helps to optimize the imaging quality of the optical module, enhance the light focusing ability, and improve the stability of the optical module. By reasonably designing the curvature ratio of CV5 and CV7, it can be ensured that the light maintains consistent focusing characteristics when passing through the first lens 3 and the second lens 4, thereby providing a high-quality visual experience.

[0118] In the case of the combination of 0≤CV6 / CV7≤2.9 and the CV5 / CV7 ratio, that is, when these two ratio ranges are satisfied at the same time, the overall performance of the optical module can be further optimized. By controlling the curvature ratio relationship of these three surfaces (fifth surface S5, sixth surface S6, and seventh surface S7), more efficient light transmission, more accurate focusing, and better imaging quality can be achieved. This helps to improve the overall performance and user experience of near-eye display devices.

[0119] Furthermore, the optical module satisfies: 0.454≤CV6 / CV7≤2.34. Controlling the ratio of the curvature CV6 of the sixth surface S6 of the second lens 4 to the curvature CV7 of the seventh surface within this range helps to optimize the transmission path and focusing effect of the light inside the second lens 4. An appropriate curvature ratio can ensure that the light can maintain a suitable refraction angle and focusing position when passing through the sixth surface S6 and the seventh surface S7, thereby improving the imaging quality. A reasonable CV6 / CV7 ratio design can reduce aberrations and distortions caused by curvature mismatch.

[0120] In some examples of this application, see Figure 1 The first prism 1 includes a first surface S1 and a second surface S2, wherein the second surface S2 is a bonding surface where the first prism 1 and the second prism 2 are bonded to each other, and the polarized reflection element 7 is arranged on the second surface S2; the curvature of the first surface S1 is CV1, the curvature of the seventh surface S7 is CV7, and 0≤|CV1 / CV7|≤0.4.

[0121] According to this example of the present application, the prism structure is specifically as follows:

[0122] See also Figure 1 The first prism 1 includes a first surface S1 and a second surface S2, the second surface S2 is a bonding surface where the first prism 1 and the second prism 2 are bonded to each other, and the polarized reflective element 7 is disposed on this surface. The seventh surface S7 is a surface of the second lens 4, which is a partial reflection surface and has a specific curvature CV7.

[0123] The ratio relationship of 0≤|CV1 / CV7|≤0.4 indicates that the absolute value of CV1 will not exceed 0.4 times the absolute value of CV7. This means that the curvature of the first surface S1 is smaller than that of the seventh surface S7, or it can be said that the first surface S1 can be closer to a plane than the seventh surface S7.

[0124] When |CV1 / CV7| is close to 0, it means that the curvature of the first surface S1 is almost 0, that is, the first surface S1 is close to a plane. Such a design can simplify the processing and manufacturing process of the first prism 1 and reduce the light refraction error caused by the curved surface.

[0125] The upper limit is set to avoid excessive curvature of the first surface S1, which may cause excessive refraction or distortion of light when passing through the first surface S1. If the absolute value of CV1 / CV7 exceeds 0.4, the first surface S1 may have an adverse effect on the light, reducing the imaging quality of the entire optical module.

[0126] According to this example of the present application, by reasonably controlling the ratio between CV1 and CV7, it is possible to ensure that the light can maintain a good refraction direction when passing through the first prism 1, providing a good foundation for the subsequent light path. The smaller curvature of the first surface S1 helps to reduce the aberration caused by the curved surface refraction, thereby improving the imaging quality of the optical module.

[0127] In addition, a reasonable curvature ratio relationship helps to enhance the stability of the optical module, enabling it to maintain good performance in a variety of environments and usage conditions.

[0128] In some examples of this application, see Figure 1 , the first surface S1 is a curved surface or a flat surface, and the second surface S2 is a flat surface.

[0129] In the optical module provided in the embodiment of the present application, the first surface S1 of the first prism 1 can be a curved surface or a flat surface. The curved surface design can further adjust the light path and focusing characteristics, while the flat surface design simplifies the manufacturing process.

[0130] As described in the above example, when |CV1 / CV7| is close to 0, the first surface S1 is a plane.

[0131] The second surface S2 is used as the bonding surface of the first prism 1 and the second prism 2. Designing the second surface S2 as a plane can ensure accurate alignment and stable bonding between the two prisms. The plane design also facilitates the attachment and positioning of the polarized reflective element 7.

[0132] In addition, by optimizing the design of the first surface S1 and the second surface S2 of the first prism 1, light distortion and stray light interference can be reduced, thereby improving the clarity of the image.

[0133] That is to say, the first prism 1 may include two flat surfaces, or may include at least one curved surface.

[0134] In some examples of this application, see Figure 1 , the angle θ1 formed between the second surface S2 and the vertical direction is an acute angle.

[0135] In this example of the present application, the angle θ1 between the second surface S2 and the vertical direction is designed to be an acute angle. The design of this angle has a crucial influence on the refraction path of the light inside the first prism 1.

[0136] When light enters the first prism from air or other media, it will be refracted according to the incident angle and the refractive index of the prism material. The design of the angle θ1 is to ensure that the light can be refracted inside the first prism 1 along the expected path, and then reach the human eye S0 through subsequent optical elements.

[0137] The sharp angle θ1 design allows the cemented prism to achieve a more compact structural design while maintaining a larger field of view, which is of great significance for the lightweight and miniaturization of near-eye display devices.

[0138] In some examples of this application, see Figure 1 The second prism 2 also includes a third surface S3 and an eighth surface S8; an air gap is provided between the third surface S3 and the fourth surface S4, and the third surface S3 is a plane; the eighth surface S8 is the top surface of the second prism 2, and the angle θ2 formed by the optical axis of the eighth surface S8 and the horizontal direction is an acute angle.

[0139] The third surface S3 is a plane, which helps the light to be totally reflected on the third surface S3, thereby optimizing the light path. The plane design also simplifies the manufacturing and processing process of the second prism 2.

[0140] About air gap: An air gap is provided between the third surface S3 of the second prism 2 and the fourth surface S4 of the first lens 3. This air gap is intended to utilize the difference in refractive index between air and prism material to achieve total reflection of light on the third surface S3. This reduces the loss of light inside the second prism 2 and improves the utilization of light. Total reflection also helps to maintain the polarization state of light, which is essential for achieving efficient polarization conversion and reducing stray light.

[0141] Regarding the eighth surface S8 of the second prism 2, which is the top surface of the second prism 2, the angle θ2 formed by the optical axis and the horizontal direction is an acute angle. The light path can be further adjusted to meet specific imaging requirements and field of view requirements. In addition, the acute angle θ2 design also helps to achieve a more compact optical structure.

[0142] It should be noted that the horizontal direction here refers to the optical axis direction of the first lens 3 and the second lens 4 .

[0143] The planar design of the third surface S3 of the second prism 2, the air gap between the third surface S3 and the fourth surface S4, and the acute angle design of the eighth surface S8 together achieve the optimization of the light path, the use of total reflection, the improvement of imaging quality, and the enhancement of the stability of the entire optical module. These designs not only improve the optical performance of the near-eye display device, but also provide users with a clearer and higher-quality visual experience.

[0144] In some examples of this application, see Figure 1 The optical module also includes a display screen 8, and the display screen 8 is arranged on one side of the eighth surface S8.

[0145] The display screen 8 is disposed on one side of the eighth surface S8 of the second prism 2. This position enables the light emitted by the display screen 8 to directly enter the second prism 2, and then be polarized, reflected and refracted by the combination of the prism and the lens, and finally reach the user's eyes.

[0146] Optionally, a protective glass 9 is provided on the light emitting surface of the display screen 8 .

[0147] The display screen 8 is an important component of the optical module, and its display effect directly affects the user experience. The protective glass 9 serves as a protective barrier for the display screen 8 and can resist external damages such as scratches, impacts and abrasion, thereby extending the service life of the display screen 8.

[0148] In some examples of this application, see Figure 1 , the fourth surface S4 is a plane, and the fifth surface S5 is a curved surface.

[0149] The surface of the first lens 3 close to the second prism 2 is the fourth surface S4, and the fourth surface S4 is a plane: the planar design simplifies the manufacturing and processing process, and helps the light to be incident on the first lens 3 in a more uniform manner.

[0150] Another surface of the first lens 3 is a fifth surface S5, which is designed as a curved surface. The curved surface design allows for finer refraction and focusing of light, thereby optimizing imaging quality. The fifth surface S5 with a curved surface design can better control the refraction and focusing of light, thereby reducing aberrations and distortions and improving image clarity.

[0151] The first lens 3 adopts a combination of plane design and curved surface design, which achieves precise control of the light propagation path and optimizes the optical performance of the optical module.

[0152] In some examples of the present application, the sixth surface S6 is a plane, and the seventh surface S7 is a plane or a curved surface.

[0153] The sixth surface S6 and the seventh surface S7 are two surfaces of the second lens 4 respectively; wherein the sixth surface S6 is a plane: the planar design makes this part of the second lens 4 easier to manufacture and process, and helps to maintain the stability of light inside the lens.

[0154] The seventh surface S7 is a flat surface or a curved surface: the design flexibility of the seventh surface allows adjustment according to specific application requirements. The flat surface design simplifies the manufacturing process, while the curved surface design provides more precise light control.

[0155] The above two examples show the effects of different surface designs of the first lens 3 and the second lens 4 on the performance of the near-eye display device. By controlling the surface design of the lens, the imaging quality can be optimized and the manufacturing cost can be reduced. These designs not only improve the optical performance of the optical module, but also provide users with a clearer and higher-quality visual experience.

[0156] In some examples of the present application, the optical module includes at most 4 curved surfaces.

[0157] The advantages of having multiple curved surfaces in an optical module include many aspects, which are described below.

[0158] From the perspective of improving imaging quality, multiple curved surfaces can more accurately control the refraction and reflection paths of light, thereby reducing aberrations and distortions and improving imaging quality.

[0159] From the perspective of enhancing the flexibility of optical module design: more curved surfaces mean more design parameters that can be adjusted, thus enhancing the design flexibility of the module. For example, the performance of the module, such as field of view and resolution, can be optimized by adjusting the curved surface parameters.

[0160] In addition, in some complex application scenarios, such as near-eye display devices that require a large field of view or high resolution, multiple curved surfaces can provide better optical performance.

[0161] However, in optical modules, too many curved surfaces can also bring some defects, as follows:

[0162] Multiple curved surfaces mean more complex optical designs, requiring more calculations and optimization work, which can lead to longer optical design cycles and increased design costs.

[0163] Multiple curved surfaces increase the difficulty of processing and assembly, requiring higher precision and more complex processes. This will lead to higher production costs and a certain risk of processing errors.

[0164] The increase in the number of curved surfaces may lead to an increase in the weight and volume of optical components, which is not conducive to lightweight and miniaturized near-eye display devices.

[0165] The optical module design of the embodiment of the present application includes at most 4 curved surfaces.

[0166] For example, the first surface S1 of the first prism 1 is a curved surface, the fifth surface S5 of the first lens 3 is a curved surface, and the sixth surface S6 and the seventh surface S7 of the second lens 4 are curved surfaces. This design can optimize the light path while ensuring effective transmission of light, reduce unnecessary refraction and reflection, and thus reduce light loss. By designing the shape and parameters of the curved surface, aberrations and distortions can be reduced, imaging quality can be improved, and a clearer visual experience can be provided to users.

[0167] Compared with designs with more curved surfaces, optical modules with up to 4 curved surfaces are simpler to design and process. This not only reduces design costs, but also reduces the complexity and potential errors in the processing process, and improves production efficiency and yield rate. In addition, the design with up to 4 curved surfaces allows the optical module to have better flexibility and adaptability while maintaining certain performance.

[0168] In practical applications, it is necessary to comprehensively consider factors such as specific needs, design cost, production cost, and optical module performance to select the most appropriate number of surfaces. In this application, it is preferred to use up to 4 surfaces.

[0169] In some examples of the present application, the centers of the first surface S1, the fifth surface S5, the sixth surface S6 and the seventh surface S7 are all located on the same optical axis, and the positive direction of the vector height of the first surface S1, the fifth surface S5, the sixth surface S6 and the seventh surface S7 is the direction away from the human eye S0 along the optical axis.

[0170] In the present application, the first surface S1, the fifth surface S5, the sixth surface S6 and the seventh surface S7 may be curved surfaces, and their positive sagittal directions are defined as directions away from the human eye S0 along the optical axis. This means that after the light is emitted from the display screen 8, it will propagate along these surfaces in a direction away from the human eye S0, and after a series of reflections and refractions, it reaches the human eye to form a clear image.

[0171] The design of the positive direction of the sag is crucial to controlling the propagation path and focal point of light. By ensuring that the positive direction of the sag of each surface is consistent, it can be ensured that the light can maintain a certain directionality and focus during propagation, thereby improving the imaging quality.

[0172] In some examples of this application, see Figure 1 , the chief light of the 0 degree field of view coincides with the optical axes of the fifth surface S5, the sixth surface S6, the seventh surface S7 and the eighth surface S8.

[0173] According to this example of the present application, during the propagation process, although the light passes through the deflections of prisms and lenses, it always remains in a coaxial optical path, that is, the light always passes through the optical axes of all elements instead of forming an off-axis system.

[0174] The main light of the 0-degree field of view coincides with the optical axis of all key surfaces, which ensures that the light has minimal aberration and distortion when passing through these surfaces. This design can significantly improve the imaging quality and make the image clearer. The design of the coaxial optical path greatly simplifies the optical design and calculation process of the optical module.

[0175] The light always propagates along the optical axis, reducing the loss at the edge of the prism and lens. This helps to improve the utilization of light energy, allowing more light to reach the human eye and enhance the imaging brightness of the optical module.

[0176] The design of the coaxial optical path simplifies the manufacturing and assembly process of optical components. Optical components can be positioned and fixed more accurately, thereby improving the stability and reliability of the entire optical module.

[0177] According to another embodiment of the present application, a near-eye display device is also provided, and the near-eye display device includes the optical module as described above.

[0178] The near-eye display device is, for example, an AR device or an XR device.

[0179] The optical module provided by the present application is described in detail below through Examples 1 to 6.

[0180] Example 1

[0181] See also Figure 2, the optical module provided in this embodiment 1 includes a cemented prism, a first lens 3 and a second lens 4, and the first lens 3 is located between the cemented prism and the second lens 4;

[0182] The glued prism includes a first prism 1, a second prism 2 and a polarized reflection element 7 glued between the two prisms;

[0183] The first lens 3 includes a fourth surface S4 and a fifth surface S5, the fourth surface S4 and the second prism 2 are adjacent and spaced apart; the fourth surface S4 is a plane, and the fifth surface S5 is a curved surface;

[0184] The second lens 4 includes a sixth surface S6 and a seventh surface S7, the seventh surface S7 is away from the first lens 3, and the seventh surface S7 is a partial reflection surface; the sixth surface S6 is a plane, and the seventh surface S7 is a plane or a curved surface;

[0185] A phase retarder 6 is arranged on the fourth surface S4;

[0186] The first prism 1 includes a first surface S1 and a second surface S2, the second surface S2 is a bonding surface where the first prism 1 and the second prism 2 are bonded to each other, and the polarized reflective element 7 is disposed on the second surface S2; the first surface S1 is a curved surface or a plane, the second surface S2 is a plane, and an angle θ1 formed between the second surface S2 and the vertical direction is an acute angle;

[0187] The second prism 2 includes a third surface S3 and an eighth surface S8; an air gap is provided between the third surface S3 and the fourth surface S4, and the third surface S3 is a plane; the eighth surface S8 is the top surface of the second prism 2, and the angle θ2 formed by the optical axis of the eighth surface S8 and the horizontal direction is an acute angle;

[0188] The optical module further includes a display screen 8, and the display screen 8 is disposed on one side of the eighth surface S8;

[0189] The centers of the first surface S1, the fifth surface S5, the sixth surface S6 and the seventh surface S7 are all located on the same optical axis, and the positive direction of the sag height of the first surface S1, the fifth surface S5, the sixth surface S6 and the seventh surface S7 is the direction away from the human eye S0 along the optical axis.

[0190] The chief ray of the 0 degree field of view coincides with the optical axes of the fifth surface S5 , the sixth surface S6 , the seventh surface S7 , and the eighth surface S8 .

[0191] The parameters of each optical element in the optical module provided in this embodiment 1 are shown in Table 1.

[0192] Table 1

[0193]

[0194] For Table 1, see Figure 2 , the distance from S0 to S1 is t0, the distance from S1 to S2 is t1, the distance from S2 to S3 is t2, the distance from S3 to S4 is t3, the distance from S4 to S5 is t4, the distance from S5 to S6 is t5, the distance from S6 to S7 is t6, the distance from S5 to S8 is t7, the distance from S8 to S9 is t8, and the distance from S9 to S10 is t9.

[0195] The EFL involved in this embodiment 1 15 / EFL, EFL 67 / EFL, EFL 45 / EFL 67 For the optical parameter ratios such as |CV5 / CV7, CV6 / CV7, |CV1 / CV7|, etc., please refer to Table 7 shown after Example 6.

[0196] See also Figure 3 The MTF diagram of the optical module shown in the figure shows the modulation transfer function at different spatial frequencies and is used to evaluate the performance of the optical module. Figure 3 In the figure, the horizontal axis represents spatial frequency and the vertical axis shows modulation, with values ​​ranging from 1.0 (representing perfect imaging) to close to 0 (indicating no imaging). Figure 3 There are multiple curves in the diagram, each corresponding to the MTF value under different conditions. These conditions are indicated by symbols next to the curves, which reflect the measured data at different wavelengths and angles. Figure 3 It can be seen that in the low frequency band (i.e. the area on the left side of the horizontal axis), the MTF values ​​of all curves are close to 1.0, indicating that the optical imaging quality in this area is relatively excellent.

[0197] Example 2

[0198] See also Figure 4 The optical module shown in this embodiment 2 has an optical architecture that is the same as that of embodiment 1, except for the optical parameters in the optical module. Please refer to Table 2 for the optical parameters of the optical module provided in this embodiment 2.

[0199] Table 2

[0200]

[0201] For Table 2, see Figure 4, the distance from S0 to S1 is t0, the distance from S1 to S2 is t1, the distance from S2 to S3 is t2, the distance from S3 to S4 is t3, the distance from S4 to S5 is t4, the distance from S5 to S6 is t5, the distance from S6 to S7 is t6, the distance from S5 to S8 is t7, the distance from S8 to S9 is t8, and the distance from S9 to S10 is t9.

[0202] The EFL involved in this embodiment 2 15 / EFL, EFL 67 / EFL, EFL 45 / EFL 67 For the optical parameter ratios such as |CV5 / CV7, CV6 / CV7, |CV1 / CV7|, etc., please refer to Table 7 shown after Example 6.

[0203] Figure 5 Contains multiple curves, each corresponding to the MTF value under different conditions. Figure 5 It can be seen that in the low frequency band (i.e. the area on the left side of the horizontal axis), the MTF values ​​of all curves are close to 1.0, indicating that the optical imaging quality in this area is relatively excellent.

[0204] Example 3

[0205] See also Figure 6 The optical module shown in this embodiment 3 has an optical architecture that is the same as that of embodiment 1, except for the optical parameters in the optical module. Please refer to Table 3 for the optical parameters of the optical module provided in this embodiment 3.

[0206] Table 3

[0207]

[0208] For Table 3, see Figure 6 , the distance from S0 to S1 is t0, the distance from S1 to S2 is t1, the distance from S2 to S3 is t2, the distance from S3 to S4 is t3, the distance from S4 to S5 is t4, the distance from S5 to S6 is t5, the distance from S6 to S7 is t6, the distance from S5 to S8 is t7, the distance from S8 to S9 is t8, and the distance from S9 to S10 is t9.

[0209] The EFL involved in this embodiment 3 15 / EFL, EFL 67 / EFL, EFL 45 / EFL 67 For the optical parameter ratios such as |CV5 / CV7, CV6 / CV7, |CV1 / CV7|, etc., please refer to Table 7 shown after Example 6.

[0210] Figure 7 Contains multiple curves, each corresponding to the MTF value under different conditions. Figure 7It can be seen that in the low frequency band (i.e. the area on the left side of the horizontal axis), the MTF values ​​of all curves are close to 1.0, indicating that the optical imaging quality in this area is relatively excellent.

[0211] Example 4

[0212] See also Figure 8 The optical module shown in this embodiment 4 has an optical architecture that is the same as that of embodiment 1, except for the optical parameters in the optical module. Please refer to Table 4 for the optical parameters of the optical module provided in this embodiment 4.

[0213] Table 4

[0214]

[0215] For Table 4, see Figure 8 , the distance from S0 to S1 is t0, the distance from S1 to S2 is t1, the distance from S2 to S3 is t2, the distance from S3 to S4 is t3, the distance from S4 to S5 is t4, the distance from S5 to S6 is t5, the distance from S6 to S7 is t6, the distance from S5 to S8 is t7, the distance from S8 to S9 is t8, and the distance from S9 to S10 is t9.

[0216] The EFL involved in this embodiment 4 15 / EFL, EFL 67 / EFL, EFL 45 / EFL 67 For the optical parameter ratios such as |CV5 / CV7, CV6 / CV7, |CV1 / CV7|, etc., please refer to Table 7 shown after Example 6.

[0217] Fig. 9 Contains multiple curves, each corresponding to the MTF value under different conditions. Fig. 9 It can be seen that in the low frequency band (i.e. the area on the left side of the horizontal axis), the MTF values ​​of all curves are close to 1.0, indicating that the optical imaging quality in this area is relatively excellent.

[0218] Example 5

[0219] See also Fig.10 The optical module shown in this embodiment 5 has an optical architecture that is the same as that of embodiment 1, except for the optical parameters in the optical module. Please refer to Table 5 for the optical parameters of the optical module provided in this embodiment 5.

[0220] Table 5

[0221]

[0222] For Table 5, see Fig.10, the distance from S0 to S1 is t0, the distance from S1 to S2 is t1, the distance from S2 to S3 is t2, the distance from S3 to S4 is t3, the distance from S4 to S5 is t4, the distance from S5 to S6 is t5, the distance from S6 to S7 is t6, the distance from S5 to S8 is t7, the distance from S8 to S9 is t8, and the distance from S9 to S10 is t9.

[0223] The EFL involved in this embodiment 5 15 / EFL, EFL 67 / EFL, EFL 45 / EFL 67 For the optical parameter ratios such as |CV5 / CV7, CV6 / CV7, |CV1 / CV7|, etc., please refer to Table 7 shown after Example 6.

[0224] Fig.11 Contains multiple curves, each corresponding to the MTF value under different conditions. Fig.11 It can be seen that in the low frequency band (i.e. the area on the left side of the horizontal axis), the MTF values ​​of all curves are close to 1.0, indicating that the optical imaging quality in this area is relatively excellent.

[0225] Example 6

[0226] See also Fig.12 The optical module shown in this embodiment 6 has an optical architecture that is the same as that of embodiment 1, except for the optical parameters in the optical module. Please refer to Table 6 for the optical parameters of the optical module provided in this embodiment 6.

[0227] Table 6

[0228]

[0229] For Table 6, see Fig.12 , the distance from S0 to S1 is t0, the distance from S1 to S2 is t1, the distance from S2 to S3 is t2, the distance from S3 to S4 is t3, the distance from S4 to S5 is t4, the distance from S5 to S6 is t5, the distance from S6 to S7 is t6, the distance from S5 to S8 is t7, the distance from S8 to S9 is t8, and the distance from S9 to S10 is t9.

[0230] The EFL involved in this embodiment 6 15 / EFL, EFL 67 / EFL, EFL 45 / EFL 67 For the optical parameter ratios such as |CV5 / CV7, CV6 / CV7, |CV1 / CV7|, etc., please refer to Table 7 shown after Example 6.

[0231] Fig.13There are multiple curves in the diagram, each corresponding to the MTF value under different conditions. These conditions are indicated by symbols next to the curves, which reflect the measured data at different wavelengths and angles. Fig.13 It can be seen that in the low frequency band (i.e. the area on the left side of the horizontal axis), the MTF values ​​of all curves are close to 1.0, indicating that the optical imaging quality in this area is relatively excellent.

[0232] Table 7 Optical parameters of Examples 1 to 6

[0233]

[0234] 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.

[0235] 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 only for illustration, not for limiting the scope of the present application. It should be understood by those skilled in the art that the above embodiments 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 for XR optical equipment, characterized in that: It comprises a cemented prism, a first lens (3) and a second lens (4), wherein the first lens (3) is located between the cemented prism and the second lens (4); The glued prism comprises a first prism (1), a second prism (2) and a polarized reflection element (7) glued between the two prisms; The first lens (3) comprises a fourth surface (S4) and a fifth surface (S5), and the fourth surface (S4) and the second prism (2) are adjacent and spaced apart; The second lens (4) comprises a sixth surface (S6) and a seventh surface (S7), the seventh surface (S7) is away from the first lens (3), and the seventh surface (S7) is a partial reflection surface; A phase retarder (6) is arranged on the fourth surface (S4) or the sixth surface (S6); The optical module meets the following conditions: 1.9≤EFL 15 / EFL≤5.4; where EFL 15 is the total effective focal length of the cemented prism and the first lens (3), and EFL is the effective focal length of the optical module.

2. The optical module according to claim 1, characterized in that: The optical module satisfies: 1.5≤EFL 67 / EFL≤51.4; where EFL 67 It is the effective focal length of light incident from the sixth surface (S6), reflected from the seventh surface (S7), and then emitted from the sixth surface (S6).

3. The optical module according to claim 2, characterized in that: The optical module satisfies: 1.78≤EFL 67 / EFL≤7.

32.

4. The optical module according to claim 2, characterized in that: The optical module satisfies: 0≤EFL 45 / EFL 67 ≤3.6; among which, EFL 45 It is the effective focal length of light incident from the fourth surface (S4) and emitted from the fifth surface (S5).

5. The optical module according to claim 1, characterized in that: The curvature of the fifth surface (S5) is CV5, the curvature of the seventh surface (S7) is CV7, and 1.5≤CV5 / CV7≤4.

6. The optical module according to claim 1, characterized in that: The curvature of the sixth surface (S6) is CV6, the curvature of the seventh surface (S7) is CV7, and 0≤CV6 / CV7≤2.

9.

7. The optical module according to claim 1, characterized in that: The first prism (1) comprises a first surface (S1) and a second surface (S2), wherein the second surface (S2) is a bonding surface where the first prism (1) and the second prism (2) are bonded to each other, and the polarized reflection element (7) is arranged on the second surface (S2); The curvature of the first surface (S1) is CV1, the curvature of the seventh surface (S7) is CV7, and 0≤|CV1 / CV7|≤0.

4.

8. The optical module according to claim 7, characterized in that: The first surface (S1) is a curved surface or a flat surface, and the second surface (S2) is a flat surface.

9. The optical module according to claim 8, characterized in that: An angle θ1 formed between the second surface (S2) and the vertical direction is an acute angle.

10. The optical module according to claim 8, characterized in that: The second prism (2) further comprises a third surface (S3) and an eighth surface (S8); An air gap is provided between the third surface (S3) and the fourth surface (S4), and the third surface (S3) is a plane; The eighth surface (S8) is the top surface of the second prism (2), and the angle θ2 formed by the optical axis of the eighth surface (S8) and the horizontal direction is an acute angle.

11. The optical module according to claim 10, characterized in that: The optical module further comprises a display screen (8), and the display screen (8) is arranged on one side of the eighth surface (S8).

12. The optical module according to claim 1, wherein: The fourth surface (S4) is a plane, and the fifth surface (S5) is a curved surface.

13. The optical module according to claim 1, characterized in that: The sixth surface (S6) is a plane, and the seventh surface (S7) is a plane or a curved surface.

14. The optical module according to claim 1, characterized in that: The optical module includes at most 4 curved surfaces.

15. The optical module according to claim 11, characterized in that: The centers of the first surface (S1), the fifth surface (S5), the sixth surface (S6) and the seventh surface (S7) are all located on the same optical axis, and the positive direction of the vector height of the first surface (S1), the fifth surface (S5), the sixth surface (S6) and the seventh surface (S7) is the direction away from the human eye (S0) along the optical axis.

16. The optical module according to claim 15, characterized in that: The chief ray of the 0-degree field of view coincides with the optical axes of the fifth surface (S5), the sixth surface (S6), the seventh surface (S7) and the eighth surface (S8).

17. A near-eye display device, characterized in that: Comprising the optical module as described in any one of claims 1-16.

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