Near-eye optical system and head-mounted display device

Abstract

This application provides a near-eye optical system and a head-mounted display device. The near-eye optical system includes a lens barrel and a first optical element disposed within the lens barrel. The first optical element includes at least a first lens, a polarization reflection element, a phase retarder, and a beam splitter. A light-shielding element is provided around one surface of the first lens. The lens barrel includes a first support section, a second support section, and a transition section connecting the first support section and the second support section. The first optical element is disposed in the first support section. The transition section forms a target angle θ1 with respect to the optical axis of the near-eye optical system, where θ1 < 90°. The near-eye optical system satisfies tan(θ1)*(T1-L1+L5)≤50, where T1 is the total optical length of the near-eye optical system, L1 is the distance from the center point O of the surface of the first lens with the light-shielding element to point A, and point A is the orthogonal projection point of the connection point between the transition section and the second support section on the optical axis of the near-eye display system. L5 is the length of the transition section.

Description

Technical Field

[0001] This application relates to the field of optical display technology, and more specifically, to a near-eye optical system and a head-mounted display device. Background Technology

[0002] In existing VR optical solutions, the field of view of the optical system is generally positively correlated with its volume; that is, the larger the field of view, the larger the volume of the optical system. In the design of VR products, in order to ensure a larger field of view, the volume of the optical system is often sacrificed, resulting in a larger optical system and thus affecting the size of the VR product. This contradicts the current trend of miniaturization and thinning of virtual reality optical product solutions. Summary of the Invention

[0003] The purpose of this application is to provide a new technical solution for a near-eye optical system and a head-mounted display device, which can achieve a small-volume design of the near-eye optical system under a large field of view.

[0004] In a first aspect, this application provides a near-eye optical system. The near-eye optical system includes a lens barrel and a first optical element disposed within the lens barrel;

[0005] The first optical element includes at least a first lens, a polarization reflection element, a phase delayer, and a beam splitter, wherein a light-shielding element is provided around one surface of the first lens;

[0006] The lens barrel includes a first support section, a second support section, and a transition section connecting the first support section and the second support section; the first optical element is disposed in the first support section, and the transition section forms a target angle θ1 with respect to the optical axis of the near-eye optical system, and θ1 < 90°;

[0007] The near-eye optical system satisfies: tan(θ1)*(T1-L1+L5)≤50, where T1 is the total optical length of the near-eye optical system, L1 is the distance from the center point O of the surface of the first lens on the side where the light-shielding element is located to point A, and point A is the orthogonal projection point of the connection point between the transition section and the second bearing section on the optical axis of the near-eye display system, and L5 is the length of the transition section.

[0008] Optionally, the light-shielding element is a light-shielding ring, and the inner edge of the light-shielding element has a first sharp corner structure;

[0009] The angle of the first sharp corner structure is θ2, and abs(θ2)≥5°.

[0010] Optionally, the near-eye optical system includes a display, which is connected to the end of the second support section away from the transition section via a bracket;

[0011] The light-shielding element is located on the edge region of the first lens on the surface away from the display.

[0012] Optionally, the support includes a main body segment and an extension segment connected to the main body segment;

[0013] The extension section is connected to the second bearing section, and the main body section forms a set angle θ3 with the optical axis, where θ3 < 90°.

[0014] The display is located at the end of the main body segment away from the extension segment.

[0015] Optionally, the near-eye optical system further includes a second optical element, which is disposed within the second support section of the lens barrel and is located on the same optical axis as the first optical element;

[0016] The second optical element includes at least one lens.

[0017] Optionally, the second optical element includes at least a third lens;

[0018] The extension of the bracket is arranged around the edge region of the surface of the third lens near the display.

[0019] A second extension is formed at the connection point between the transition section and the second bearing section, and the second extension is arranged around the edge region of the surface of the third lens away from the display.

[0020] Optionally, the display is configured to emit natural light or circularly polarized light;

[0021] When the light emitted by the display is natural light, a composite film is provided on the light-emitting surface of the display. The composite film includes two phase retardation plates and a polarizer disposed between the two phase retardation plates, which can be used to convert natural light into circularly polarized light.

[0022] Optionally, the beam-splitting element is disposed on the surface of the first lens near the display;

[0023] The phase delayer and the polarization reflection element are stacked and disposed on the surface of the first lens away from the display.

[0024] Optionally, the first optical element further includes a polarizing element, which is stacked with the polarizing reflective element and the phase retarder to form a composite element, with the polarizing reflective element located between the polarizing element and the phase retarder.

[0025] Optionally, the first optical element further includes a second lens, which is disposed on the side of the first lens opposite to the side where the light-shielding element is disposed;

[0026] A spacer element is provided between the first lens and the second lens, and the spacer element is disposed between the edge region of the first lens and the edge region of the second lens.

[0027] Optionally, the transition section and the first bearing section are connected at point B to form a first extension section, and the first extension section is arranged around the edge region of the second lens near the display.

[0028] Optionally, the near-eye optical system satisfies: (L2+L4) / L3≥5, where L2 is the thickness of the edge region of the first lens, L4 is the thickness of the edge region of the second lens, and L3 is the thickness of the spacer element.

[0029] Optionally, the spacer element has a ring-shaped structure, and the inner edge of the spacer element has a second pointed corner structure;

[0030] The angle of the second sharp-angled structure is θ4, and abs(θ4)≥5°.

[0031] Optionally, if the thickness L3 of the spacer element is ≤0.1mm, the spacer element is an opaque Mylar sheet.

[0032] Optionally, the display is configured to emit natural light or circularly polarized light;

[0033] When the light emitted by the display is natural light, a composite film is disposed on the surface of the third lens away from the display. The composite film includes two phase retardation plates and a polarizer disposed between the two phase retardation plates, which can be used to convert natural light into circularly polarized light.

[0034] Optionally, the beam-splitting element is disposed on the surface of the second lens near the display;

[0035] The phase delayer and the polarization reflection element are stacked and disposed on the surface of the first lens near the display.

[0036] Optionally, the first optical element further includes a polarizing element, which is stacked with the polarizing reflective element and the phase retarder to form a composite element, with the polarizing reflective element located between the polarizing element and the phase retarder.

[0037] Secondly, this application provides a head-mounted display device. The head-mounted display device includes:

[0038] Casing; and

[0039] The near-eye optical system as described in the first aspect.

[0040] The beneficial effects of this application are as follows:

[0041] The near-eye optical system provided in this application is an optical architecture based on a folded optical path. By reasonably constraining the optical parameters and adding light-blocking elements to block stray light, a virtual reality solution with a large field of view and small size is achieved under the new optical architecture, while also ensuring good image quality. The near-eye optical system provided in this application has excellent optical performance.

[0042] Other features and advantages of this specification will become clear from the following detailed description of exemplary embodiments with reference to the accompanying drawings. Attached Figure Description

[0043] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments of this specification and, together with their description, serve to explain the principles of this specification.

[0044] Figure 1 This is one of the structural schematic diagrams of the near-eye optical system provided in the embodiments of this application;

[0045] Figure 2 for Figure 1 A dot array diagram of the near-eye optical system is provided.

[0046] Figure 3 for Figure 1 The modulation transfer function (MTF) plot of the near-eye optical system is provided.

[0047] Figure 4 for Figure 1 Field curvature and distortion diagrams of the near-eye optical system are provided;

[0048] Figure 5 for Figure 1 A chromatic aberration diagram of a near-eye optical system is provided.

[0049] Figure 6 This is a second schematic diagram of the near-eye optical system provided in the embodiments of this application;

[0050] Figure 7 A schematic diagram of one embodiment of introducing an optical element that forms a folded optical path in a near-eye optical system;

[0051] Figure 8 A schematic diagram illustrating one embodiment of introducing a composite element into a near-eye optical system;

[0052] Figure 9 One of the partial structural schematic diagrams of the lens barrel provided in the embodiments of this application;

[0053] Figure 10 A partial structural schematic diagram of the first optical element provided in an embodiment of this application;

[0054] Figure 11 A second partial structural schematic diagram of the lens barrel provided in an embodiment of this application;

[0055] Figure 12 for Figure 6 A dot array diagram of the near-eye optical system is provided.

[0056] Figure 13 for Figure 6 The modulation transfer function (MTF) plot of the near-eye optical system is provided.

[0057] Figure 14 for Figure 6 Field curvature and distortion diagrams of the near-eye optical system are provided;

[0058] Figure 15 for Figure 6 A chromatic aberration diagram of a near-eye optical system is provided.

[0059] Figure 16 This is the third schematic diagram of the near-eye optical system provided in the embodiments of this application;

[0060] Figure 17 for Figure 16 A dot array diagram of the near-eye optical system is provided.

[0061] Figure 18 for Figure 16 The modulation transfer function (MTF) plot of the near-eye optical system is provided.

[0062] Figure 19 for Figure 16 Field curvature and distortion diagrams of the near-eye optical system are provided;

[0063] Figure 20 for Figure 16 A chromatic aberration diagram of a near-eye optical system is provided.

[0064] Figure 21 Fourth schematic diagram of the near-eye optical system provided in the embodiments of this application;

[0065] Figure 22 for Figure 21 A dot array diagram of the near-eye optical system is provided.

[0066] Figure 23 for Figure 21 The modulation transfer function (MTF) plot of the near-eye optical system is provided.

[0067] Figure 24 for Figure 21 Field curvature and distortion diagrams of the near-eye optical system are provided;

[0068] Figure 25 for Figure 21 The provided diagram shows the chromatic aberration of the near-eye optical system.

[0069] Explanation of reference numerals in the attached figures:

[0070] 1. Display; 2. Stand; 21. Main body section; 22. Extension section; 3. Third lens; 31. Fifth surface; 32. Sixth surface; 4. Second lens; 41. Third surface; 42. Fourth surface; 5. First lens; 51. First surface; 52. Second surface; 6. Human eye; 7. Light-shielding element; 71. First sharp corner structure; 8. Spacer element; 9. Lens barrel; 91. First support section; 92. Second support section; 93. Transition section; 94. First extension section; 95. Second extension section; 10. Polarizing reflection element; 11. Phase retarder; 12. Beam splitter; 13. Polarizing element; 14. First anti-reflective film; 15. Phase retarder; 16. Polarizer; 17. Second anti-reflective film; 18. Screen protection element. Detailed Implementation

[0071] 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, numerical expressions, and values ​​of the components and steps set forth in these embodiments do not limit the scope of the present application.

[0072] The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the scope of this application and its application or use.

[0073] Technologies and equipment known to those skilled in the art may not be discussed in detail, but where appropriate, such technologies and equipment should be considered part of the specification.

[0074] In all the examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values.

[0075] It should be noted that similar labels and letters in the following figures indicate similar items; therefore, once an item is defined in one figure, it does not need to be discussed further in subsequent figures.

[0076] The near-eye optical system and head-mounted display device provided in the embodiments of this application will be described in detail below with reference to the accompanying drawings.

[0077] According to one aspect of the embodiments of this application, a near-eye optical system is provided, which can be used in virtual reality display devices, such as VR head-mounted displays. Specifically, the VR head-mounted display device includes VR smart glasses or VR smart helmets, etc., and the embodiments of this application do not limit the specific form of the head-mounted display device.

[0078] The near-eye optical system proposed in this application's embodiments is described in [reference]. Figure 1 and Figure 6 The near-eye optical system includes a lens barrel 9 and a first optical element disposed within the lens barrel 9. The first optical element includes at least a first lens 5, a polarizing reflective element 10, a phase retarder 11, and a beam splitter 12. A light-shielding element 7 is provided around one surface of the first lens 5. The lens barrel 9 includes a first support section 91, a second support section 92, and a transition section 93 connecting the first support section 91 and the second support section 92. The first optical element is disposed within the first support section 91. The transition section 93 forms a target angle θ1 with respect to the optical axis of the near-eye optical system, and θ1 < 90°. The near-eye optical system satisfies: tan(θ1)*(T1-L1+L5)≤50, where T1 is the total optical length of the near-eye optical system, L1 is the distance from point O to point A on the surface of the first lens 5 where the light-shielding element 7 is located, and point A is the orthogonal projection point of the connection point between the transition section 93 and the second support section 92 on the optical axis of the near-eye display system, and L5 is the length of the transition section 93. See [link to documentation]. Figure 9 .

[0079] According to the near-eye optical system provided in the above embodiments, the surface of the first lens 5 where the light-shielding element 7 is disposed can be flat or convex. See [link / reference] Figure 1 and Figure 6 This surface can be close to the human eye.

[0080] The near-eye optical system provided according to the above embodiments includes a lens barrel 9, which is used to carry the main optical components within the near-eye optical system. See also Figure 9 The lens barrel 9 is not a straight cylindrical structure, but rather has a sloping wall structure. The introduction of the lens barrel 9 facilitates the assembly of the entire near-eye optical system onto products such as VR devices.

[0081] According to the near-eye optical system provided in the above embodiment, a first optical element is disposed within the lens barrel 9. The first optical element can be used to receive light emitted by an external device, such as a display 1, for imaging display, and transmit the light to the imaging position, for example... Figure 1 and Figure 6 An image is formed at the location of the human eye 6 shown in the image.

[0082] The first optical element includes at least one lens, namely the first lens 5 mentioned above, and also includes multiple optical elements forming a folded optical path, such as the polarizing reflector 10, the phase retarder 11, and the beam splitter 12 mentioned above, so that light can be refracted within the first optical element. The design of the folded optical path can reduce the overall optical length of the near-eye optical system while ensuring image quality.

[0083] The optical architecture of the near-eye optical system provided in the above embodiments can be found in [reference needed]. Figure 1 and Figure 6 A light-shielding element 7 is disposed on the surface of the first lens 5 near the human eye 6. Specifically, the light-shielding element 7 is arranged around the edge region of the surface of the first lens 5 near the human eye 6. The light-shielding element 7 can effectively block the field of view outside the optically effective field of view and reduce stray light.

[0084] See Figure 9 Based on the light-shielding element 7 surrounding one surface of the first lens 5, the near-eye optical system should satisfy the constraint that tan(θ1)*(T1-L1+L5)≤50mm, where T1 is the total optical length of the near-eye optical system, L1 is the distance between the center of the convex surface of the first lens 5 and point A, and point A is the orthogonal projection point of the connection point between the transition section 93 and the second bearing section 92 on the optical axis of the near-eye display system, and L5 is the length of the transition section 93. It should be noted that the units of T1, L1, and L5 are all mm. By constraining the above parameters of the near-eye optical system in this application, the overall volume of the near-eye optical system can be effectively reduced.

[0085] Specifically, compared with traditional folded optical path solutions, the near-eye optical system provided in this application embodiment has a significantly reduced volume, for example, the volume can be reduced by more than 1 / 5 of that of traditional optical solutions.

[0086] The near-eye optical system provided in this application embodiment is an optical architecture based on a folded optical path. By reasonably constraining the optical parameters and adding a light-blocking element 7 to block stray light, a virtual reality solution with a large field of view and small size is achieved under the new optical architecture, while also ensuring good image quality. The near-eye optical system provided in this application embodiment has excellent optical performance. The field of view (FOV) of the near-eye optical system provided in this application embodiment can reach over 95 degrees.

[0087] The near-eye optical system provided in the above embodiments of this application has the advantage of small size, which enables the thin and light design of virtual reality devices (VR devices) using the near-eye optical system. This is more suitable for users to wear and use, can improve wearing comfort, and will not cause fatigue even after wearing for a long time.

[0088] The near-eye optical system provided in this application embodiment is a folded optical path optical architecture. For example, in addition to introducing a lens, a beam splitter 12, a phase delayer 11, and a polarization reflection element 10 are also introduced into the first optical element. This can be used to form a folded optical path in the first optical element, so that the light is reflected back in it, thereby extending the propagation path of the light and facilitating the final clear imaging.

[0089] The beam splitting element 12 is, for example, a semi-transparent and semi-reflective film.

[0090] It should be noted that the reflectivity and transmittance of the beam splitter 12 can be flexibly adjusted according to specific needs, and this embodiment does not impose any restrictions on this.

[0091] The phase delayer 11 is, for example, a quarter-wave plate.

[0092] Of course, the phase delayer 11 mentioned here can also be configured as other phase delay plates such as half-wave plates as needed.

[0093] The phase delayer 11 can be used to convert linearly polarized light into circularly polarized light, or to convert circularly polarized light into linearly polarized light.

[0094] The polarization reflecting element 10 is, for example, a linear polarizer, which is a polarization reflector that reflects horizontally linearly polarized light and transmits vertically linearly polarized light, or any other polarization reflector that reflects linearly polarized light at a specific angle and transmits linearly polarized light in a direction perpendicular to that angle.

[0095] The near-eye optical system provided in this application embodiment is beneficial for realizing a virtual reality optical solution with a large field of view and a small volume.

[0096] See some examples in this application. Figures 9 to 11The light-shielding element 7 is a light-shielding ring, and the inner edge of the light-shielding element 7 has a first sharp corner structure 71. The angle of the first sharp corner structure 71 is θ2, and abs(θ2)≥5°.

[0097] According to the above example, a light-blocking element 7 is provided on the surface of the first lens 5 near the human eye 6. The light-blocking element 7 is a ring structure and a sharp corner structure, namely the first sharp corner structure 71, can be provided on its inner ring. The design of the first sharp corner structure 71 can make the position of blocking light more accurate, thereby achieving better blocking of field light outside the optical effective field of view and further reducing stray light.

[0098] When the angle of the first sharp corner structure 71 is θ2, which satisfies the condition that abs(θ2)≥5°, the effect of reducing stray light is better.

[0099] In other words, the absolute value of the angle θ2 of the first sharp corner structure 71 should be designed to be no less than 5°. It should be noted that the direction of the sharp corner on the light-shielding element 7 can be adjusted.

[0100] See some examples in this application. Figure 1 and Figure 6 The near-eye optical system includes a display 1, which is connected to the end of the second support section 92 away from the transition section 93 via a bracket 2. The light-shielding element 7 is located on the edge region of the surface of the first lens 5 away from the display 1.

[0101] The display 1 is capable of emitting light for imaging and display.

[0102] A screen protection element 18 may be disposed on the light-emitting surface of the display 1, see [reference]. Figure 6 The screen protection element 18 can effectively protect the display 1.

[0103] The lens barrel 9 is a three-section design, comprising a first support section 91, a transition section 93, and a second support section 92 connected in sequence. The first optical element is disposed within the first support section 91, and the display 1 is disposed within the second support section 92. In this architecture, the first optical element and the display 1 are located at opposite ends of the lens barrel 9. Since the size of the first optical element is larger than that of the display 1, the transition section 93 on the lens barrel 9 is tilted between the first optical element and the display 1. In the optical scheme of this embodiment, the tilt angle θ1 of the transition section 93 relative to the optical axis is constrained to satisfy the following relationship: tan(θ1)*(T1-L1+L5)≤50mm. This effectively reduces the volume of the entire near-eye optical system in a large field of view, for example, by more than 1 / 5 of the conventional solution.

[0104] It should be noted that in the constraint tan(θ1)*(T1-L1+L5)≤50mm provided in the embodiments of this application, T1 is the total length of the near-eye optical system, which may include the display 1 or may not include the display 1.

[0105] The lens barrel 9 may be composed of a first support section 91, a transition section 93 and a second support section 92 connected in sequence, and the lens barrel 9 is an integrally formed structure.

[0106] See some examples in this application. Figure 1 and Figure 6 The bracket 2 includes a main body segment 21 and an extension segment 22 connected to the main body segment 21; wherein the extension segment 22 is connected to the second bearing segment 92, and the main body segment 21 forms a set angle θ3 with the optical axis, where θ3 < 90°. The display 1 is located at the end of the main body segment 21 furthest from the extension segment 22.

[0107] According to the above example, the bracket 2 is a connector connecting the display 1 and the lens barrel 9. It is not a straight cylindrical structure, but rather comprises two sections: a main body section 21 and an extension section 22. The extension section 22 is connected to one end of the second supporting section 92 of the lens barrel 9. The extension section 22 can be a straight-walled structure to provide some obstruction or positioning for the edge area of ​​the lens positioned therein. See also... Figures 9 to 11 The main body segment 21 has a certain tilt angle relative to the optical axis, and its tilt range can be consistent with the transition segment 93 of the lens barrel 9. This design can reduce the volume of the near-eye optical system.

[0108] The main body segment 21 and the extension segment 22 are connected as a whole to form the support 2.

[0109] See some examples in this application. Figure 1 The near-eye optical system further includes a second optical element, which is disposed on the second support section 92 of the lens barrel 9 and is located on the same optical axis as the first optical element; the second optical element includes at least one lens.

[0110] According to the near-eye optical system provided in the embodiments of this application, an optical element can be added to the side closer to the display 1, that is, a second optical element as described above can be set between the first optical element and the display 1, which can improve the optical performance of the near-eye optical system.

[0111] See some examples in this application. Figure 1 The second optical element includes at least a third lens 3; the extension 22 of the bracket 2 is arranged around the edge region of the surface of the third lens 3 near the display 1; a second extension 95 is formed at the connection point of the transition section 93 and the second support section 92, and the second extension 95 is arranged around the edge region of the surface of the third lens 3 away from the display 1.

[0112] According to the above example, after the third lens 3 is arranged on the side close to the display 1, the extension 22 of the bracket 2 can be used to block the edge area of ​​the third lens 3 on the surface of the display 1. Furthermore, the second extension 95 at the connection point A between the transition section 93 and the second support section 92 can block the edge area of ​​the third lens 3 away from the display 1. This design allows the third lens 3 to block light rays outside the optically effective field of view, which is beneficial for reducing stray light.

[0113] Meanwhile, the extension section 22 and the second extension section 95 can also position and support the third lens 3, facilitating the assembly of the third lens 3 in the lens barrel 9.

[0114] In some examples of this application, the display 1 is configured to emit either natural light or circularly polarized light. When the light emitted by the display 1 is natural light, a composite film is disposed on the light-emitting surface of the display 1. The composite film includes two phase retardation plates 15 and a polarizer 16 disposed between the two phase retardation plates 15, which can be used to convert natural light into circularly polarized light.

[0115] When only the first lens 5 and the third lens 3 mentioned above are used in the near-eye optical system, the composite film can be placed on the display 1.

[0116] The composite film is used to convert natural light into circularly polarized light. The composite film incorporates two phase retarders 15 to reduce stray light. The phase retarders are, for example, quarter-wave plates.

[0117] Optionally, a second antireflective film 17 may also be introduced into the composite film material.

[0118] In some examples of this application, the beam splitter 12 is disposed on the surface of the first lens 5 close to the display 1; the phase delayer 11 and the polarization reflection element 10 are stacked and disposed on the surface of the first lens 5 away from the display 1.

[0119] In some examples of this application, the first optical element further includes a polarizing element 13, which is stacked with the polarizing reflective element 10 and the phase retarder 11 to form a composite element, with the polarizing reflective element 10 located between the polarizing element 13 and the phase retarder 11.

[0120] The polarizing element 13 is, for example, a linear polarizer (or polarizer).

[0121] The polarization element 13 is aligned with the transmission direction of the polarization reflection element 10, and the use of the polarization element 13 can reduce ghosting and stray light.

[0122] Optionally, a first anti-reflective film 14 may be provided on the surface of the phase delayer 11 that is away from the polarization reflective element 10.

[0123] See some examples in this application. Figure 6 The first optical element further includes a second lens 4, which is disposed on the side of the first lens 5 opposite to the side where the light-shielding element 7 is disposed. A spacer element 8 is disposed between the first lens 5 and the second lens 4, and the spacer element 8 abuts against the edge region of the first lens 5 and the edge region of the second lens 4.

[0124] For the near-eye optical system provided in this application embodiment, the number of optical lenses can be increased in the first optical element. For example, see... Figure 6 A second lens 4 is introduced into the first optical element. That is, the first optical element may include a first lens 5 and a second lens 4. The second lens 4 is positioned closer to the display 1 than the first lens 5. The introduction of the second lens 4 helps reduce the overall optical length of the near-eye optical system and improves image quality.

[0125] When the first lens 5 and the second lens 4 described above are used in the first optical element, a spacer element 8 needs to be introduced between them. Specifically, the spacer element 8 can be disposed between the edge regions of the two optical lenses, which can effectively block field light outside the effective optical field of view. By using it in conjunction with the light-shielding element 7, stray light can be reduced even better.

[0126] See some examples in this application. Figure 6 The transition section 93 and the first bearing section 91 are connected at position B to form a first extension section 94, and the first extension section 94 is arranged around the edge region of the second lens 4 near the surface of the display 1.

[0127] According to the above example, the first extension segment 94 extending from the connection position B between the transition segment 93 and the first bearing segment 91 can form a certain shielding in the edge area of ​​the second lens 4 near the display 1, and can form a shielding cooperation with the spacer element 8.

[0128] Meanwhile, the first extension section 94 can position the second lens 4 within the lens barrel 9, facilitating the installation of the second lens 4.

[0129] See some examples in this application. Figure 11 The near-eye optical system satisfies: (L2+L4) / L3≥5, where L2 is the thickness of the edge region of the first lens 5, L4 is the thickness of the edge region of the second lens 4, and L3 is the thickness of the spacer element 8.

[0130] According to the above example, when the near-eye optical system satisfies (L2+L4) / L3≥5, the assembly feasibility of the second lens 4 and the spacer element 8 can be guaranteed.

[0131] In some examples of this application, the spacer element 8 is in the form of a ring, and the inner edge of the spacer element 8 has a second pointed corner structure; the angle of the second pointed corner structure is θ4, and abs(θ4)≥5°.

[0132] The spacer element 8 is a spacer ring disposed between two optical lenses. A second pointed structure can be provided on its inner ring to make the position of blocking light more accurate. Among them, when the angle θ4 of the second pointed structure satisfies abs(θ2)≥5°, the effect of reducing stray light is better.

[0133] In some examples of this application, when the thickness L3 of the spacer element 8 is ≤0.1mm, the spacer element 8 is an opaque Mylar sheet.

[0134] In the near-eye optical system provided in this application embodiment, when a spacer element 8 is introduced between the first lens 5 and the second lens 4, the spacer element 8 has thickness limitations during assembly and manufacturing, and should be as thin as possible. Mylar film can be made very thin, which meets the assembly and optical performance requirements.

[0135] Among them, black ring-shaped Mylar sheets can be used.

[0136] In other words, when L3≤0.1mm, black Mylar film can be used to replace the spacer ring. Black Mylar film has a thin sheet structure and is lighter and thinner.

[0137] In some examples of this application, the display 1 is configured to emit either natural light or circularly polarized light; when the light emitted by the display 1 is natural light, a composite film is disposed on the surface of the third lens 3 away from the display 1. The composite film includes two phase retardation plates 15 and a polarizer 16 disposed between the two phase retardation plates 15. See [reference needed] Figure 8 It can be used to convert natural light into circularly polarized light.

[0138] Based on the above example, the composite film is used to convert natural light into circularly polarized light. The composite film incorporates two phase retarders 15 to reduce stray light. The phase retarders are, for example, quarter-wave plates.

[0139] When three lenses are used in a near-eye optical system, such as Figure 6 The optical architecture shown allows the composite film to be disposed on the surface of the third lens 3 away from the display 1.

[0140] If the near-eye optical system uses two lenses, such as Figure 1 The optical architecture shown allows the composite film to be disposed on the light-emitting surface of the display 1, enabling the display 1 to directly emit circularly polarized light.

[0141] Optionally, see Figure 8 A second antireflective film 17 may also be introduced into the composite film material.

[0142] In some examples of this application, the beam-splitting element 12 is disposed on the surface of the second lens 4 near the display 1; see also Figure 7 The phase delayer 11 and the polarization reflection element 10 are stacked and disposed on the surface of the first lens 5 near the display 1.

[0143] The beam splitter 12 is, for example, a quarter-wave plate, which can be directly mounted or plated onto the surface of the second lens 4 near the display 1. Figure 6The phase retarder 11 and the polarizing reflective element 10 are stacked together and disposed on the surface of the first lens 5 near the display 1. Figure 6 On the first surface 51 shown in the figure. There is no need to introduce a separate flat plate support to support the optical elements described above in the optical architecture.

[0144] Placing the polarizing reflection element 10 and the phase delayer 11 on the same side of the first lens 5 helps to reduce the difficulty of the assembly process.

[0145] The polarization reflection element 10 has a reflection direction that forms an angle of 45° with the fast axis or slow axis of the phase delayer 11.

[0146] See some examples in this application. Figure 7 The first optical element further includes a polarizing element 13, which is stacked with the polarizing reflective element 10 and the phase delayer 11 to form a composite element, with the polarizing reflective element 10 located between the polarizing element 13 and the phase delayer 11.

[0147] The polarizing element 13 is, for example, a linear polarizer (or polarizer).

[0148] The polarization element 13 is aligned with the transmission direction of the polarization reflection element 10, and the use of the polarization element 13 can reduce ghosting and stray light.

[0149] Optionally, see Figure 7 A first anti-reflective film 14 may be provided on the surface of the phase delayer 11 that is away from the polarization reflection element 10.

[0150] It should be noted that the near-eye optical system provided in this application does not impose a specific limit on the number of optical lenses used, but a minimum of one optical lens, i.e., the first lens 5, is used. In practical applications, the number of lenses can be designed according to specific needs. Increasing the number of lenses can improve the imaging effect and appropriately reduce the overall optical length of the system, but it may increase the weight and production cost of the entire near-eye optical system.

[0151] As a preferred embodiment of this application, the near-eye optical system may use three lenses. In this case, the optical performance of the near-eye optical system is better.

[0152] See Figures 6 to 8 The light propagation process of the near-eye optical system is as follows:

[0153] Natural light emitted by the display 1 remains natural light after passing through a phase retarder 15 on the surface of the third lens 3, becomes linearly polarized light after passing through a polarizer 16, becomes circularly polarized light after passing through another phase retarder 15, is transmitted through the second lens 4, becomes linearly polarized light (S light) after passing through a phase retarder 11 on the surface of the first lens 5, is reflected by the polarization reflection element 10, becomes circularly polarized light after passing through the phase retarder 11 again, is reflected by a beam splitting element 12 on the surface of the second lens 4, becomes linearly polarized light (P light) after passing through the phase retarder 11 on the surface of the first lens 5, and then is transmitted through the first lens 5 and enters the human eye 6 for imaging.

[0154] According to the near-eye optical system provided by the embodiments of the present application, refer to Figure 6 , which may include three lenses, such as a first lens 5, a second lens 4, and a third lens 3 arranged along the same optical axis.

[0155] Optionally, the refractive index n of the materials used for the optical lenses included in the near-eye optical system ranges from 1.4 < n < 1.7, and the dispersion coefficient v ranges from 20 < v < 75.

[0156] For example, the refractive index n1 of the first lens 5 is 1.54, and the dispersion coefficient v1 is 55.7. The refractive index n2 of the second lens 4 is 1.54, and the dispersion coefficient v2 is 56.3. The refractive index n3 of the third lens 3 is 1.54, and the dispersion coefficient v3 is 56.3.

[0157] Among them, the central thickness T1 of the first lens 5 is, for example: 1 mm ≤ T1 ≤ 8 mm. The optical power φ1 of the first lens 5 is 0 < φ1 < 0.1.

[0158] The first lens 5 includes two optical surfaces, namely a first surface 51 close to the display 1 and a second surface 52 far from the display 1.

[0159] Both the first surface 51 and the second surface 52 are aspherical or planar.

[0160] A film layer structure can be provided on the first surface 51, such as Figure 7 shown, including a first anti-reflection film 14, a polarization element 13 (transmitting P light), a polarization reflection element 10 (transmitting P light and reflecting S light), and a phase retarder 11. The polarization element 13 can reduce stray light.

[0161] In addition, an anti-reflection film can be selectively provided on the second surface 52.

[0162] The center thickness T2 of the second lens 4 is 1mm ≤ T2 ≤ 8mm. The optical power φ2 of the second lens 4 is 0 < φ2 < 0.1.

[0163] The second lens 4 includes two optical surfaces, namely a third surface 41 close to the display 1 and a fourth surface 42 away from the display 1.

[0164] The third surface 41 and the fourth surface 42 are aspherical.

[0165] A beam splitting element 12, i.e., a semi-transmissive and semi-reflective film, can be provided on the third surface 41.

[0166] The fourth surface 42 can be a plane or an aspherical surface, and an anti-reflective film layer can be selectively applied to the fourth surface 42.

[0167] The center thickness T3 of the third lens 3 is 1mm ≤ T3 ≤ 8mm. The optical power φ3 of the third lens 3 is 0 ≤ φ3 < 0.01.

[0168] The third lens 3 includes two optical surfaces, namely a fifth surface 31 close to the display 1 and a sixth surface 32 away from the display 1.

[0169] The fifth surface 31 and the sixth surface 32 can be aspherical or planar.

[0170] Among them, the fifth surface 31 can be provided with such Figure 8 The composite film shown includes a second antireflective film 17, two phase retarders 15 (quarter-wave plates), and a polarizer 16 located between the two phase retarders 15. An antireflective film layer may also be optionally provided on the sixth surface 32.

[0171] The near-eye optical system provided in this application will be described below through four embodiments.

[0172] Example 1

[0173] See Figure 1 The near-eye optical system includes a lens barrel 9, and a first optical element, a second optical element, and a display 1 disposed within the lens barrel 9 and located on the same optical axis;

[0174] The display 1 is capable of emitting natural light. A composite film is provided on the light-emitting surface of the display 1. The composite film includes two phase retardation plates 15 and a polarizer 16 disposed between the two phase retardation plates 15.

[0175] The first optical element includes a first lens 5. A beam splitting element 12 is disposed on the surface of the first lens 5 near the display 1. A polarizing element 13, a polarizing reflective element 10, and a phase retarder 11 are stacked on the surface of the first lens 5 away from the display 1, and the phase retarder 11 is located between the beam splitting element 12 and the polarizing reflective element 10. A light-shielding element 7 is arranged around the edge region of the first lens 5 away from the display 1.

[0176] The second optical element includes a third lens 3;

[0177] See Figures 9 to 11 The lens barrel 9 includes a first support section 91, a second support section 92, and a transition section 93 connecting the first support section 91 and the second support section 92; the first optical element is disposed in the first support section 91, and the transition section 93 forms a target angle θ1 with respect to the optical axis of the near-eye optical system, where θ1 < 90°; the second optical element is disposed in the second support section 92; the display 1 is connected to the end of the second support section 92 away from the transition section 93 via a bracket 2;

[0178] The bracket 2 includes a main body segment 21 and an extension segment 22 connected to the main body segment 21; wherein, the extension segment 22 is connected to the second support segment 92, the main body segment 21 forms a set angle θ3 with the optical axis, and θ3 < 90°; the extension segment 22 of the bracket 2 is arranged around the edge region of the surface of the third lens 3 near the display 1; the transition segment 93 of the lens barrel 9 forms a second extension segment 95 at the connection position A of the second support segment 92, and the second extension segment 95 is arranged around the edge region of the surface of the third lens 3 away from the display 1.

[0179] Table 1 shows the optical parameters of the near-eye optical system, as detailed below.

[0180] Table 1

[0181]

[0182]

[0183] The optical performance of the near-eye optical system provided in Embodiment 1 is as follows: Figures 2 to 5 As shown: Figure 2 This is a schematic diagram of the dot array of the near-eye optical system. Figure 3 This is the MTF curve of the near-eye optical system. Figure 4 This is a field curvature distortion diagram of the near-eye optical system. Figure 5 It is a chromatic aberration diagram of the near-eye optical system.

[0184] A dot pattern refers to the diffuse pattern formed by numerous rays emanating from a single point and passing through a near-eye optical system. Due to aberrations, their intersections with the image plane no longer converge at a single point, but instead create a scattered pattern over a certain area. This pattern can be used to evaluate the imaging quality of a near-eye optical system. See also Figure 2 As shown, the maximum value of the image point in the point array is less than 17μm.

[0185] The MTF curve is a modulation transfer function graph, which characterizes the imaging sharpness of near-eye optical systems through the contrast of black and white line pairs. See also Figure 3 As shown, the center MTF is >0.3 at 40 lp / mm, and the image is clear.

[0186] See Figure 4 The maximum distortion occurs in the field of view 1, with an absolute value of less than 40%.

[0187] Transverse chromatic aberration, also known as magnification chromatic aberration, mainly refers to the difference in focal positions between blue and red light on the image plane when a single polychromatic principal ray from the object side is emitted as multiple rays due to dispersion in the refraction system. (See also...) Figure 5 As shown, the maximum chromatic aberration value of the near-eye optical system is less than 200 μm.

[0188] Example 2

[0189] The difference between Example 2 and Example 1 is that a second lens 4 is introduced into the first optical element, and the mounting positions of each optical film are different.

[0190] See Figures 6 to 8 The near-eye optical system includes a lens barrel 9, and a first optical element, a second optical element, and a display 1 disposed within the lens barrel 9 and located on the same optical axis. The display 1 is configured to emit natural light.

[0191] The first optical element includes a first lens 5 and a second lens 4. A beam splitter 12 is disposed on the surface of the second lens 4 near the display 1. A polarizing element 13, a polarizing reflective element 10, and a phase retarder 11 are stacked on the surface of the first lens 5 near the display 1, and the phase retarder 11 is located between the beam splitter 12 and the polarizing reflective element 10. A light-shielding element 7 is disposed around the edge region of the first lens 5 away from the display 1. A spacer element 8 is disposed between the first lens 5 and the second lens 4, and the spacer element 8 abuts between the edge region of the first lens 5 and the edge region of the second lens 4.

[0192] The second optical element includes a third lens 3, and a composite film is disposed on the surface of the third lens 3 away from the display 1. The composite film includes two phase retardation plates 15 and a polarizer 16 disposed between the two phase retardation plates 15.

[0193] See Figures 9 to 11 The lens barrel 9 includes a first support section 91, a second support section 92, and a transition section 93 connecting the first support section 91 and the second support section 92;

[0194] The first optical element is disposed within the first carrier section 91, and the transition section 93 forms a target angle θ1 with respect to the optical axis of the near-eye optical system, where θ1 < 90°.

[0195] The second optical element is disposed within the second carrier section 92;

[0196] The display 1 is connected to the end of the second support section 92 away from the transition section 93 via a bracket 2; the bracket 2 includes a main body section 21 and an extension section 22 connected to the main body section 21; wherein, the extension section 22 is connected to the second support section 92, and the main body section 21 forms a set angle θ3 with the optical axis, and θ3 < 90°;

[0197] The near-eye optical system satisfies: (L2+L4) / L3≥5, where L2 is the thickness of the edge region of the first lens, L4 is the thickness of the edge region of the second lens, and L3 is the thickness of the spacer element.

[0198] The extension 22 of the bracket 2 is arranged around the edge region of the surface of the third lens 3 near the display 1; the transition section 93 of the lens barrel 9 forms a second extension 95 at the connection position A of the second support section 92, and the second extension 95 is arranged around the edge region of the surface of the third lens 3 away from the display 1; the transition section 93 forms a first extension 94 at the connection position B of the first support section 91, and the first extension 94 is arranged around the edge region of the surface of the second lens 4 near the display 1.

[0199] Table 2 shows the optical parameters of the near-eye optical system, as detailed below.

[0200] Table 2

[0201]

[0202]

[0203] The optical performance of the near-eye optical system provided in Embodiment 2 is as follows: Figures 12 to 15 As shown: Figure 12This is a schematic diagram of the dot array of the near-eye optical system. Figure 13 This is the MTF curve of the near-eye optical system. Figure 14 This is a field curvature distortion diagram of the near-eye optical system. Figure 15 It is a chromatic aberration diagram of the near-eye optical system.

[0204] A dot pattern refers to the diffuse pattern formed by numerous rays emanating from a single point and passing through a near-eye optical system. Due to aberrations, their intersections with the image plane no longer converge at a single point, but instead create a scattered pattern over a certain area. This pattern can be used to evaluate the imaging quality of a near-eye optical system. See also Figure 12 As shown, the maximum value of the image point in the point array is less than 9μm.

[0205] The MTF curve is a modulation transfer function graph, which characterizes the imaging sharpness of near-eye optical systems through the contrast of black and white line pairs. See also Figure 13 As shown, the center MTF is >0.5 at 40 lp / mm, and the image is clear.

[0206] See Figure 14 The maximum distortion occurs in the field of view 1, with an absolute value of less than 40%.

[0207] Transverse chromatic aberration, also known as magnification chromatic aberration, mainly refers to the difference in focal positions between blue and red light on the image plane when a single polychromatic principal ray from the object side is emitted as multiple rays due to dispersion in the refraction system. (See also...) Figure 15 As shown, the maximum chromatic aberration value of the near-eye optical system is less than 200 μm.

[0208] Example 3

[0209] See Figure 16 This illustrates the near-eye optical system provided in Embodiment 3, which differs from the near-eye optical system shown in Embodiment 2 in the parameters of the optical elements.

[0210] Table 3 shows the optical parameters of the near-eye optical system, as detailed below.

[0211] Table 3

[0212]

[0213] The optical performance of the near-eye optical system provided in Embodiment 3 is as follows: Figures 17 to 20 As shown: Figure 17 This is a schematic diagram of the dot array of the near-eye optical system. Figure 18 This is the MTF curve of the near-eye optical system. Figure 19 This is a field curvature distortion diagram of the near-eye optical system. Figure 20 It is a chromatic aberration diagram of the near-eye optical system.

[0214] A dot pattern refers to the diffuse pattern formed by numerous rays emanating from a single point and passing through a near-eye optical system. Due to aberrations, their intersections with the image plane no longer converge at a single point, but instead create a scattered pattern over a certain area. This pattern can be used to evaluate the imaging quality of a near-eye optical system. See also Figure 17 As shown, the maximum value of the image point in the point array is less than 21 μm.

[0215] The MTF curve is a modulation transfer function graph, which characterizes the imaging sharpness of near-eye optical systems through the contrast of black and white line pairs. See also Figure 18 As shown, the center MTF is >0.4 at 40 lp / mm, and the image is clear.

[0216] See Figure 19 The maximum distortion occurs in the field of view 1, with an absolute value of less than 40%.

[0217] Transverse chromatic aberration, also known as magnification chromatic aberration, mainly refers to the difference in focal positions between blue and red light on the image plane when a single polychromatic principal ray from the object side is emitted as multiple rays due to dispersion in the refraction system. (See also...) Figure 20 As shown, the maximum chromatic aberration value of the near-eye optical system is less than 200 μm.

[0218] Example 4

[0219] See Figure 21 This illustrates the near-eye optical system provided in Embodiment 4, which differs from the near-eye optical system shown in Embodiment 2 in the parameters of the optical elements.

[0220] Table 4 shows the optical parameters of the near-eye optical system, as detailed below.

[0221] Table 4

[0222]

[0223] The optical performance of the near-eye optical system provided in Embodiment 4 is as follows: Figures 22 to 25 As shown: Figure 22 This is a schematic diagram of the dot array of the near-eye optical system. Figure 23 This is the MTF curve of the near-eye optical system. Figure 24 This is a field curvature distortion diagram of the near-eye optical system. Figure 25 It is a chromatic aberration diagram of the near-eye optical system.

[0224] A dot pattern refers to the diffuse pattern formed by numerous rays emanating from a single point and passing through a near-eye optical system. Due to aberrations, their intersections with the image plane no longer converge at a single point, but instead create a scattered pattern over a certain area. This pattern can be used to evaluate the imaging quality of a near-eye optical system. See also Figure 22 As shown, the maximum value of the image point in the point array is less than 15μm.

[0225] The MTF curve is a modulation transfer function graph, which characterizes the imaging sharpness of near-eye optical systems through the contrast of black and white line pairs. See also Figure 23 As shown, the center MTF is >0.15 at 40 lp / mm, and the image is clear.

[0226] See Figure 24 The maximum distortion occurs in the field of view 1, with an absolute value of less than 40%.

[0227] Transverse chromatic aberration, also known as magnification chromatic aberration, mainly refers to the difference in focal positions between blue and red light on the image plane when a single polychromatic principal ray from the object side is emitted as multiple rays due to dispersion in the refraction system. (See also...) Figure 25 As shown, the maximum chromatic aberration value of the near-eye optical system is less than 200 μm.

[0228] According to another embodiment of this application, a head-mounted display device is provided.

[0229] The head-mounted display device includes a housing and a near-eye optical system as described above.

[0230] The head-mounted display device may take the form of VR glasses or VR helmets, and this application embodiment does not limit this.

[0231] The specific implementation of the head-mounted display device in this application can refer to the above-described near-eye optical system embodiments, and therefore has at least all the beneficial effects brought about by the technical solutions of the above embodiments, which will not be repeated here.

[0232] The above embodiments mainly describe 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. For the sake of brevity, they will not be elaborated here.

[0233] While specific embodiments of this application have been described in detail by way of examples, those skilled in the art should understand that the above examples are for illustrative purposes only and are not intended to limit the scope of this application. Those skilled in the art should understand that modifications can be made to the above embodiments without departing from the scope and spirit of this application. The scope of this application is defined by the appended claims.

Claims

1. A near-eye optical system, characterized by, Includes a lens barrel (9) and a first optical element disposed within the lens barrel (9); The first optical element includes at least a first lens (5), a polarization reflection element (10), a phase retarder (11), and a beam splitter (12), and a light-shielding element (7) is provided on one surface ring of the first lens (5). The lens barrel (9) includes a first support section (91), a second support section (92), and a transition section (93) connecting the first support section (91) and the second support section (92); the first optical element is disposed in the first support section (91), and the transition section (93) forms a target angle θ1 with respect to the optical axis of the near-eye optical system, and θ1 < 90°; The near-eye optical system satisfies: tan(θ1)*(T1-L1+L5)≤50, where T1 is the total optical length of the near-eye optical system, L1 is the distance from the center point O of the surface of the first lens (5) on the side where the light-shielding element (7) is located to point A, and point A is the orthogonal projection point of the connection point between the transition section (93) and the second bearing section (92) on the optical axis of the near-eye optical system, and L5 is the length of the transition section (93).

2. The near-eye optical system of claim 1, wherein, The light-shielding element (7) is a light-shielding ring, and the inner edge of the light-shielding element (7) has a first sharp corner structure (71). The angle of the first sharp corner structure (71) is θ2, and abs(θ2) ≥ 5°.

3. The near-eye optical system of claim 1 or 2, wherein, The near-eye optical system includes a display (1), which is connected to the end of the second support section (92) away from the transition section (93) via a bracket (2); The light-shielding element (7) is located on the edge region of the surface of the first lens (5) away from the display (1).

4. The near-eye optical system according to claim 3, characterized in that, The support (2) includes a main body segment (21) and an extension segment (22) connected to the main body segment (21). Wherein, the extension segment (22) is connected to the second bearing segment (92), and the main body segment (21) forms a set angle θ3 with the optical axis, and θ3 < 90°; The display (1) is located at one end of the main body segment (21) away from the extension segment (22).

5. The near-eye optical system according to claim 4, characterized in that, The near-eye optical system further includes a second optical element, which is disposed in the second support section (92) of the lens barrel (9) and is located on the same optical axis as the first optical element; The second optical element includes at least one lens.

6. The near-eye optical system according to claim 5, characterized in that, The second optical element includes at least a third lens (3); The extension (22) of the bracket (2) is arranged around the edge region of the surface of the third lens (3) near the display (1); A second extension section (95) is formed at the connection point between the transition section (93) and the second bearing section (92), and the second extension section (95) is arranged around the edge region of the surface of the third lens (3) away from the display (1).

7. The near-eye optical system according to claim 6, characterized in that, The display (1) is configured to emit natural light or circularly polarized light; When the light emitted by the display (1) is natural light, a composite film is provided on the light-emitting surface of the display (1). The composite film includes two phase delay plates (15) and a polarizer (16) disposed between the two phase delay plates (15), which can be used to convert natural light into circularly polarized light.

8. The near-eye optical system according to claim 7, characterized in that, The beam splitter (12) is disposed on the surface of the first lens (5) near the display (1); The phase delayer (11) and the polarization reflection element (10) are stacked and disposed on the surface of the first lens (5) away from the display (1).

9. The near-eye optical system according to claim 8, characterized in that, The first optical element further includes a polarizing element (13), which is stacked with the polarizing reflective element (10) and the phase delayer (11) to form a composite element, with the polarizing reflective element (10) located between the polarizing element (13) and the phase delayer (11).

10. The near-eye optical system according to claim 6, characterized in that, The first optical element further includes a second lens (4), which is disposed on the side of the first lens (5) opposite to the side where the light-shielding element (7) is disposed; A spacer element (8) is provided between the first lens (5) and the second lens (4), and the spacer element (8) is disposed between the edge region of the first lens (5) and the edge region of the second lens (4).

11. The near-eye optical system according to claim 10, characterized in that, The transition section (93) and the first bearing section (91) are connected at point B to form a first extension section (94), and the first extension section (94) is arranged around the edge region of the second lens (4) near the display (1).

12. The near-eye optical system according to claim 10, characterized in that, The near-eye optical system satisfies: (L2+L4) / L3≥5, where L2 is the thickness of the edge region of the first lens (5), L4 is the thickness of the edge region of the second lens (4), and L3 is the thickness of the spacer element (8).

13. The near-eye optical system according to claim 10, characterized in that, The spacer element (8) has a ring-shaped structure, and the inner edge of the spacer element (8) has a second sharp corner structure; The angle of the second sharp-angled structure is θ4, and abs(θ4) ≥ 5°.

14. The near-eye optical system according to claim 10, characterized in that, When the thickness L3 of the spacer element (8) is ≤0.1mm, the spacer element (8) is an opaque Mylar sheet.

15. The near-eye optical system according to claim 10, characterized in that, The display (1) is configured to emit natural light or circularly polarized light; When the light emitted by the display (1) is natural light, a composite film is provided on the surface of the third lens (3) away from the display (1). The composite film includes two phase retardation plates (15) and a polarizer (16) disposed between the two phase retardation plates (15), which can be used to convert natural light into circularly polarized light.

16. The near-eye optical system according to claim 15, characterized in that, The beam splitter (12) is disposed on the surface of the second lens (4) near the display (1); The phase delayer (11) and the polarization reflection element (10) are stacked and disposed on the surface of the first lens (5) near the display (1).

17. The near-eye optical system according to claim 16, characterized in that, The first optical element further includes a polarizing element (13), which is stacked with the polarizing reflective element (10) and the phase delayer (11) to form a composite element, with the polarizing reflective element (10) located between the polarizing element (13) and the phase delayer (11).

18. A head-mounted display device, characterized in that, include: case; as well as The near-eye optical system as described in any one of claims 1-17.

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