Combined prism type turn-back near-to-eye display system and AR glasses

Abstract

The utility model discloses a combined prism type turn-back near-to-eye display system and AR glasses, and belongs to the field of AR glasses, and the system is characterized in that the upper end of a first prism is provided with an inclined optical surface, the front end is provided with a vertical optical surface, and the rear end is provided with a gluing surface; the micro display screen is obliquely arranged above the inclined optical surface, and the display ends face the inclined optical surface at intervals; the first linear polarizer is arranged between the display end of the micro display screen and the inclined optical surface of the first prism; the second prism is vertically arranged in front of the vertical optical surface of the first prism; a diaphragm and a compensation lens are sequentially arranged in front of the second prism; the first quarter-wave plate is arranged between the vertical optical surface of the first prism and the second prism; the inclined surface at the front end of the third prism is glued with the first prism through a gluing surface, and the bottom end of the third prism is a bottom light absorption surface; the rear end of the third prism is provided with a rear concave optical surface, and the rear concave optical surface corresponds to the position of a human eye behind. The system is small in size, clear in display, matched with the human eye structure and convenient to assemble.

Description

TECHNICAL FIELD

[0001] The utility model relates to near eye display system technical field of AR glasses especially relates to a combination prism type turn back near eye display system. BACKGROUND

[0002] AR glasses (augmented reality glasses) can project virtual images and real world images into the human eye at the same time, so that the user can see the virtual image superimposed in the real scene. AR glasses can bring great convenience to people's learning, work, life, entertainment and other aspects, and the user can not only move freely when obtaining visual text, images and video information, but also has both hands free, greatly facilitating people's daily life. AR glasses technology has developed rapidly in recent years and has been successfully applied to military equipment, industrial production, medical diagnosis and daily life entertainment and many other fields. There are AR glasses on the market based on different optical principles such as planar semi-transparent semi-reflective, free-form surface semi-transparent semi-reflective, geometric light guide, catadioptric structure and diffractive light guide. Among them, the catadioptric structure (commonly known as Birdbath) has been widely used because of its good optical clarity and low optical distortion.

[0003] Although the catadioptric structure has obvious advantages compared with other optical structures such as planar semi-transparent semi-reflective, it is still difficult to meet the needs of the development of AR glasses. Users need AR glasses to have a larger FOV (field of view), and a smaller volume, but the FOV of the conventional catadioptric structure is difficult to reach 50°, and the thickness is usually greater than 15mm.

[0004] The combination prism type turn back near eye display system uses a prism structure to refract and reflect the light path, and introduces an air gap to realize total reflection transmission of the local light path, so that the system FOV reaches more than 60°, and the thickness is controlled to be less than 13mm, making up for the shortcomings of the traditional catadioptric structure (Birdbath) in FOV and thickness, and having great application potential.

[0005] Therefore, the utility model is provided. SUMMARY

[0006] The utility model discloses a combination prism type turn back near eye display system and AR glasses, and further solves the above technical problems existing in the prior art.

[0007] The utility model discloses a combination prism type turn back near eye display system and AR glasses, and further solves the above technical problems existing in the prior art.

[0008] A combination prism type turn back near eye display system comprises:

[0009] The first prism, the micro display screen, the second prism, the third prism, the first linear polarizer, the first quarter wave plate, the film and the compensation lens are combined into a combined prism type fold-back near-eye display system.

[0010] The upper end of the first prism is provided with an inclined optical surface, the front end is provided with a vertical optical surface, and the rear end is provided with a bonding surface.

[0011] The micro display screen is inclinedly arranged above the inclined optical surface of the first prism, and the display end of the micro display screen is spaced towards the inclined optical surface of the first prism.

[0012] The first linear polarizer is arranged between the display end of the micro display screen and the inclined optical surface of the first prism.

[0013] The second prism is vertically arranged in front of the vertical optical surface of the first prism.

[0014] The film and the compensation lens are sequentially arranged in front of the second prism.

[0015] The first quarter wave plate is arranged between the vertical optical surface of the first prism and the second prism.

[0016] The inclined surface at the front end of the third prism is bonded to the first prism through the bonding surface, the bottom end of the third prism is a bottom light-absorbing surface, the rear end of the third prism is provided with a rear concave optical surface, and the rear concave optical surface corresponds to the position of the human eye in the rear.

[0017] An AR (Augmented Reality) glass comprises a glass body and a near-eye display system integrated on the glass body, and the near-eye display system adopts the combined prism type fold-back near-eye display system.

[0018] Compared with the prior art, the combined prism type fold-back near-eye display system and the AR glass have the beneficial effects that:

[0019] By adopting the first prism, the second prism, the third prism, the first linear polarizer, the first quarter wave plate, the film and the compensation lens, the micro display screen is combined into a combined prism type fold-back near-eye display system, the compensation lens is arranged separately from the optical system, the system volume is further compressed, and the assembly difficulty is reduced. The film combination for eliminating light leakage is arranged, the light leakage of the imaging light to the outside world is eliminated, and the privacy of the user is protected. The planar structure of the third prism on the near-eye side is arranged as a concave surface structure, the optical modulation capacity of the optical system is improved, and the structure is more suitable for the human eye. BRIEF DESCRIPTION OF DRAWINGS

[0020] In order to more clearly illustrate the technical scheme of the embodiments of the present application, the following will briefly introduce the drawings needed to be used in the embodiment description. Obviously, the drawings described below are only some of the embodiments of the present application, and do not constitute a limitation on the present application. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without creative labor are within the protection scope of the present application.

[0021] Figure 1 The structure schematic diagram of the combined prism type turn-back near-eye display system provided by the embodiments of the present application.

[0022] Figure 2 The structure schematic diagram of the combined prism type turn-back near-eye display system provided by the embodiments of the present application.

[0023] Figure 3 The structure schematic diagram of the combined prism type turn-back near-eye display system provided by the embodiments of the present application.

[0024] Figure 4 The structure schematic diagram of the combined prism type turn-back near-eye display system provided by the embodiments of the present application.

[0025] The marks in the figure are as follows: SCN-micro display screen; POL1-first linear polarizer; PR1-first prism; S11-inclined optical surface of the first prism; S12-vertical optical surface of the first prism; S13-cemented surface of the first prism; PR2-second prism; S21-rear optical surface of the second prism; S22-front optical surface of the second prism; PR3-third prism; S31-bottom light-absorbing surface of the third prism; S32-rear concave optical surface of the third prism; FS-cemented surface of the first prism and the third prism; PBS-polarization beam splitter; QWP1-first quarter wave plate; P-film; L1-compensation lens; POL2-second linear polarizer; QWP2-second quarter wave plate; S22-front optical surface of the second prism; Eye-human eye position; p-polarized light; s-s polarized light; c-circularly polarized light. DETAILED DESCRIPTION

[0026] The technical scheme in the embodiments of the present application will be described clearly and completely in combination with the drawings in the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, and do not constitute a limitation on the present application. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without creative labor are within the protection scope of the present application.

[0027] Firstly, the terms possibly used in the present text are explained as follows:

[0028] The term "and / or" means either both or one of the referenced items, e.g. X and / or Y means both "X" or "Y" and also "X and Y".

[0029] The terms "comprise", "include", "contain", "have" or other similar semantic descriptions should be interpreted as non-exclusive inclusion. For example, the inclusion of a technical feature element (such as raw materials, components, ingredients, carriers, dosage forms, materials, sizes, parts, components, mechanisms, devices, steps, processes, methods, reaction conditions, processing conditions, parameters, algorithms, signals, data, products or articles, etc.) should be interpreted as not only including the explicitly listed technical feature element, but also including other technical feature elements not explicitly listed but known in the art.

[0030] The term "consisting of means excluding any technical feature element not explicitly listed. If this term is used in a claim, the term will make the claim closed, so that it does not contain technical feature elements other than those explicitly listed, except for conventional impurities associated therewith. If the term only appears in a certain clause of the claim, it only limits the elements explicitly listed in that clause, and the elements described in other clauses are not excluded from the overall claim.

[0031] Unless otherwise explicitly specified or limited, the terms "mount", "connect", "connection", "fixed", and the like should be interpreted broadly, for example: it can be fixed connection, can also be detachable connection, or integral connection; can be mechanical connection, can also be electrical connection; can be directly connected, can also be indirectly connected through an intermediate medium, can be internal communication of two elements. For those skilled in the art, the specific meaning of the above terms in this text can be understood according to the specific circumstances.

[0032] The terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of description and simplification of description, and are not intended to indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on this text.

[0033] The scheme provided by the utility model is described in detail below. The contents not described in detail in the utility model embodiments belong to the prior art known by the person skilled in the art. The unspecified conditions in the utility model embodiments are implemented according to the conventional conditions in the field or the conditions suggested by the manufacturer. The reagents or instruments used in the utility model embodiments are not specified by the manufacturer, and are all conventional products that can be obtained by market purchase.

[0034] As shown in Figure 1 The utility model discloses a kind of combined prism type turn-back near-eye display systems, it is characterized by comprising:

[0035] First prism, micro display screen, second prism, third prism, first linear polarizer, first quarter wave plate, diaphragm and compensating lens;Wherein,

[0036] The upper end of the first prism is provided with an inclined optical surface, the front end is provided with a vertical optical surface, and the rear end is provided with a bonding surface;

[0037] The micro display screen is inclinedly arranged above the inclined optical surface of the first prism, and the display end of the micro display screen is spaced towards the inclined optical surface of the first prism;

[0038] The first linear polarizer is arranged between the display end of the micro display screen and the inclined optical surface of the first prism;

[0039] The second prism is vertically arranged in front of the vertical optical surface of the first prism;

[0040] The diaphragm and the compensating lens are sequentially arranged in front of the second prism;

[0041] The first quarter wave plate is arranged between the vertical optical surface of the first prism and the second prism;

[0042] The inclined surface of the front end of the third prism is bonded with the first prism through the bonding surface, and the bottom end of the third prism is a bottom light-absorbing surface. The rear end of the third prism is provided with a rear concave optical surface, and the rear concave optical surface corresponds to the position of the human eye in the rear.

[0043] Referring to Figure 2 , preferably, the diaphragm of the above system is a combined diaphragm composed of a second linear polarizer and a second quarter wave plate, the second linear polarizer is located on the side close to the compensating lens, and the second quarter wave plate is located on the side close to the second prism. AR film is also attached to both sides of the diaphragm.

[0044] The bonding surface of the first prism and the third prism is provided with a polarization light splitting film.

[0045] Preferably, in the system, the polarization direction of the second linear polarizer of the film is consistent with the light transmission direction of the polarization light splitting film on the bonding surface.

[0046] The fast axis direction of the second quarter wave plate of the film is perpendicular to the fast axis direction of the first quarter wave plate.

[0047] Preferably, in the system, the front end optical surface of the second prism is coated with a semi-transparent and semi-reflective optical film, and the reflectivity r_C1 satisfies 5% < r_C1 < 90%.

[0048] The refractive power of the compensating lens is set to offset the light transmission refractive power of the combination of the first prism, the second prism and the third prism in the horizontal direction.

[0049] Preferably, in the system, the compensating lens is a dark lens.

[0050] Preferably, in the system, the fast axis of the first quarter wave plate forms a 45° angle with the light transmission axis of the polarization light splitting film.

[0051] In the first prism, the angle between the optical axis of the inclined optical surface and the normal line of the vertical optical surface is 45°-65°.

[0052] In the first prism, the angle between the bonding surface and the vertical optical surface is 20°-35°.

[0053] The optical axis of the rear concave optical surface of the third prism coincides with the normal line of the vertical surface of the first prism, and the optical axis of the rear concave optical surface of the third prism coincides with the optical axis of the front end optical surface of the second prism.

[0054] Preferably, in the system, the air gap between the first quarter wave plate and the vertical optical surface of the first prism is greater than 0.01 mm.

[0055] Preferably, in the system, the inclined optical surface of the first prism, the front end optical surface of the second prism and the rear concave optical surface of the third prism are spherical or aspherical surfaces.

[0056] The inclined optical surface of the first prism, the vertical optical surface of the first prism and the rear concave optical surface of the third prism are all coated with an anti-reflection film.

[0057] Preferably, in the system, the bottom light absorbing surface at the bottom end of the third prism is a frosted surface or a jet black surface.

[0058] Referring to Figure 3 and Figure 4Preferably, in the above system, positioning grooves are provided on both sides of the first, second, and third prisms. When the positioning grooves of the first, second, and third prisms overlap, they are assembled into a predetermined optical position. Preferably, the positioning grooves are V-shaped or arc-shaped. The provision of the positioning grooves improves the accuracy and convenience of assembling the three prisms.

[0059] Preferably, in the above system, the micro display screen adopts any one of a Micro-OLED screen, a Micro-LED screen, an LCD screen, and an original image LBS light source.

[0060] An embodiment of the present invention further provides an AR glasses, comprising: a glasses body and a near-eye display system integrated on the glasses body, characterized in that the near-eye display system adopts the above-mentioned combined prism-type reentrant near-eye display system.

[0061] In summary, the near-eye display system of the present invention adopts a first prism, a second prism, a third prism, a first linear polarizer, a first quarter-wave plate, a diaphragm and a compensating lens, and is combined with a micro-display screen to form a combined prismatic folding near-eye display system. Since the compensating lens is separated from the optical system, the system volume is further compressed and the assembly difficulty is reduced. A diaphragm combination is provided to eliminate light leakage, thereby eliminating the leakage of imaging light to the outside world and protecting the privacy of the user. The planar structure of the third prism on the near-eye side is set to an inner concave structure, which improves the optical modulation ability of the optical system while being more in line with the structure of the human eye. In addition, a positioning groove is provided on the side of the prism to facilitate mass production and assembly of the system.

[0062] In order to more clearly demonstrate the technical solution and technical effects provided by the present invention, the solution provided by the embodiments of the present invention will be described in detail with reference to specific embodiments below. Example

[0063] like Figure 1 As shown, this embodiment provides a combined prism-type folding near-eye display system, including: a micro display screen SCN, a first prism PR1, a second prism PR2, a third prism PR3, a compensation lens L1, a first linear polarizer POL and a first quarter-wave plate QWP1.

[0064] In the optical system, the micro display screen SCN can be a micro-sized organic light-emitting diode (Micro-OLED) screen, a micro-sized light-emitting diode (Micro-LED) screen, a LCD (Liquid crystal Display) screen with appropriate size, or a raw image LBS (Laser beam scanning) light source equivalent to the micro display screen.

[0065] The materials of the first prism PR1, the second prism PR2, and the third prism PR3 can be optical plastic or optical glass, and the first prism PR1 and the third prism PR3 are made of the same material.

[0066] The angle between the optical axis of the inclined optical surface S11 of the first prism PR1 and the normal line of the vertical optical surface S12 is 45° to 65°.

[0067] The first prism PR1 and the third prism PR3 are combined together by a bonding surface FS, and the bonding surface FS is the bonding surface of the two prisms. The bonding surface FS is provided with a polarization beam splitter film PBS.

[0068] The angle between the bonding surface FS and the inclined optical surface S11 of the first prism PR1 is 20° to 35°.

[0069] A first quarter wave plate QWP1 is arranged between the first prism PR1 and the second prism PR2, and an air gap (>0.01 mm) is left between the first quarter wave plate QWP1 and the vertical optical surface S12 of the first prism PR1, so that total reflection can occur inside the vertical optical surface S12. The first quarter wave plate QWP1 can be independent of the first prism PR1 and the second prism PR2, or attached to the rear optical surface S21 of the second prism PR2. The fast axis of the first quarter wave plate QWP1 is arranged at an angle of 45° with the optical axis of the polarization beam splitter film PBS.

[0070] The front optical surface S22 of the second prism PR2 is coated with a semi-transparent and semi-reflective optical film, and the reflectivity r_C1 satisfies 5% < r_C1 < 90%.

[0071] The rear concave optical surface S31 of the third prism PR3 is the optical surface of the system close to the human eye, and the optical surface is a concave surface, which is designed to match the contour shape of the eyeball of the human eye, so that the system is more comfortable when worn on the AR glasses. At the same time, the concave surface type of the optical surface S31 of the prism PR3 is designed to cooperate with other optical surfaces of the system, and compared with the mainstream plane, the optical modulation capacity is stronger, and the imaging quality of the system is higher.

[0072] The inclined optical surface S11 of the first prism PR1, the front end optical surface S22 of the second prism PR2 and the rear concave optical surface S31 of the third prism PR3 are spherical or aspherical. The inclined optical surface S11 of the first prism PR1, the vertical optical surface S12 of the first prism PR1 and the rear concave optical surface S31 of the third prism PR3 are all coated with an anti-reflection film.

[0073] The bottom end of the third prism PR3 is coated with a matte film and a black film, which is a matte surface or a black surface, to reduce stray light of the system.

[0074] After the system is assembled, the optical axis of the rear concave optical surface S31 of the third prism PR3 coincides with the normal line of the vertical optical surface S12 of the first prism PR1, and the optical axis of the rear concave optical surface S31 coincides with the optical axis of the front end optical surface S22 of the second prism PR2.

[0075] Since the optical system composed of the first prism PR1, the second prism PR2 and the third prism PR3 has a non-zero refractive power from the rear concave optical surface S31 to the front end optical surface S22, the human eye will be distorted when observing the real scene outside through the optical system composed of the three prisms, and thus cannot observe the real scene normally. The compensation lens L1 is arranged on the left side (far away from the human eye) of the optical system composed of the three prisms, and the refractive power of the compensation lens L1 is set to be just equal to the refractive power of the optical system composed of the three prisms in the horizontal direction, so that the human eye can observe the real scene outside normally through the three prisms and the compensation lens L1.

[0076] The compensation lens L1 is arranged separately from the optical system composed of the first prism PR1, the second prism PR2 and the third prism PR3. When the system is applied to an AR (Augmented Reality) glass, the AR glass usually has a dark lens on the outside (far away from the human eye) of the optical system to make the appearance of the AR glass fashionable, and to protect the optical system and the human eye. Therefore, the compensation lens L1 is set to have the function of the dark lens, and replaces the traditional dark lens of the AR glass. In this way, the thickness and weight of the system can be effectively reduced, and the assembly difficulty can be reduced, which is convenient for mass production of the system.

[0077] Referring to Figure 2 A film P is arranged between the second prism PR2 and the compensation lens L1. The film P is a combination of a second linear polarizer POL2 and a second quarter-wave plate QWP2. The second linear polarizer POL2 is located on the left side (close to the compensation lens L1), and the quarter-wave plate QWP2 is located on the right side. AR films are also attached to the two sides of the film P to reduce stray light.

[0078] The main function of the film P is to eliminate the light (leakage light) that is transmitted to the outside (left side) through the front end optical surface S22 coated with a semi-transmissive and semi-reflective film.

[0079] The polarization direction of the second linear polarizer POL2 on the film P is set to be consistent with the light transmission direction of the PBS on the glued surface FS, so that the external real scene light can pass through the system and enter the human eye.

[0080] The fast axis direction of the second quarter wave plate QWP2 on the diaphragm P is set to be perpendicular to the fast axis direction of the first quarter wave plate QWP1.

[0081] The first prism PR1, the second prism PR2 and the third prism PR3 are provided with positioning grooves (V-shaped or arc-shaped) on both sides. When the positioning grooves on both sides of the three prisms coincide ( Figure 3 V1 and Figure 4 When the three prisms are assembled into the preset optical positions (V2 in the figure), the positioning grooves can improve the assembly accuracy of the optical system, reduce the assembly difficulty, and further enhance the mass production of the system.

[0082] In this near-eye display system, light emitted by the microdisplay screen SCN is converted to s-polarized light by passing through the first linear polarizer POL. It then enters the first prism PR1 via the inclined optical surface S11. The light propagates downward and leftward within the first prism PR1, striking the vertical optical surface S12 of the first prism PR1. Because the total reflection angle is greater than that of the vertical optical surface S12, it undergoes total internal reflection and propagates downward and rightward, where it then strikes the polarization beam splitter film PBS (which transmits p-light and reflects s-light) on the bonding surface FS. The polarization beam splitter film PBS reflects the incident s-light to the left, and then strikes the vertical optical surface S12. Because the total reflection angle is less than that of the vertical optical surface S12, the light is transmitted. It is modulated by the first quarter-wave plate QWP1 into circularly polarized light (c-light), and then enters the second prism PR2. Some of the light is reflected by the front optical surface S22 of the second prism PR2, which is coated with a semi-transparent and semi-reflective film, and propagates to the right. Some of the light passes through the front optical surface S22 and continues to propagate to the left. Light (circularly polarized light) reflected and propagating rightward by the front optical surface S22 is modulated again by the first quarter-wave plate QWP1 to become p-polarized light. It successfully passes through the polarizing beam splitter film PBS and the third prism PR3 before entering the human eye and being perceived. Light transmitted by the front optical surface S22 and continuing to propagate leftward is incident on the second quarter-wave plate QWP2 to the right of the film P, where it is modulated into s-light. Because the polarization direction of the second linear polarizer POL2 to the left of the film P aligns with the transmission direction of the polarizing beam splitter film PBS, it transmits p-light and absorbs s-light. Therefore, the s-light modulated by the second quarter-wave plate QWP2 is absorbed and prevented from passing through the film P and continuing to propagate leftward, thus achieving the purpose of absorbing leakage light.

[0083] The outside real scene light propagates to the right side through the compensation lens L1, is incident on the second linear polarizer POL2 of the diaphragm P, becomes p polarized light, the p polarized light is sequentially modulated by the second quarter wave plate QWP2 and the first quarter wave plate QWP1, and the two fast axes are perpendicular to each other, and the p polarized light is still p polarized light, the p polarized light is incident into an eye through the polarizing beam splitter PBS and the prism and is perceived.

[0084] As can be seen from the above, the near-eye display system of the embodiment of the utility model separates the see-through compensation lens from the optical system, further compresses the system volume, and reduces the assembly difficulty. The diaphragm combination for eliminating light leakage is arranged, the light leakage of the imaging light to the outside world is eliminated, and the privacy of the user is protected. The plane structure of the near-eye prism is arranged as a concave structure, the optical modulation capacity of the optical system is improved, and the structure is more suitable for the human eye structure. In addition, the positioning groove is arranged on the side of the prism, and the system is convenient for mass production and assembly.

[0085] The above is only a preferred specific implementation manner of the utility model, but the protection scope of the utility model is not limited to this, any person skilled in the art can easily think of changes or replacements within the technical range disclosed by the utility model, and all should be covered in the protection scope of the utility model. Therefore, the protection scope of the utility model should be the protection scope of the claims. The information disclosed in the background art part of the paper only aims at deepening the understanding of the general background art of the utility model, and should not be regarded as acknowledging or implicitly admitting that the information constitutes the prior art known by the person skilled in the art.

Claims

1. A combined prism-type reentrant near-eye display system, characterized in that: include: a first prism, a micro display screen, a second prism, a third prism, a first linear polarizer, a first quarter wave plate, a diaphragm and a compensation lens; wherein, The first prism has an inclined optical surface at its upper end, a vertical optical surface at its front end, and a glued surface at its rear end; The micro display screen is obliquely arranged above the inclined optical surface of the first prism, and the display end of the micro display screen is spaced toward the inclined optical surface of the first prism; The first linear polarizer is disposed between the display end of the micro display screen and the inclined optical surface of the first prism; The second prism is vertically arranged in front of the vertical optical surface of the first prism; A diaphragm and a compensating lens are sequentially arranged in front of the second prism; The first quarter-wave plate is disposed between the vertical optical surface of the first prism and the second prism; The inclined surface at the front end of the third prism is glued to the first prism via a glued surface, and the bottom end of the third prism is a bottom light-absorbing surface; the rear end of the third prism is provided with a rear concave optical surface, which corresponds to the rear position of the human eye.

2. The combined prism-type reentrant near-eye display system according to claim 1, characterized in that: The film is a composite film composed of a second linear polarizing plate and a second quarter-wave plate, wherein the second linear polarizing plate is located on the side close to the compensation lens, and the second quarter-wave plate is located on the side close to the second prism; AR films are also attached to both sides of the film; A polarization splitting film is provided on the bonding surface where the first prism and the third prism are bonded.

3. The combined prism-type reentrant near-eye display system according to claim 2, characterized in that: The polarization direction of the second linear polarizer of the film is consistent with the light transmission direction of the polarization splitting film on the glued surface; The fast axis direction of the second quarter wave plate of the diaphragm is perpendicular to the fast axis direction of the first quarter wave plate.

4. The combined prism-type reentrant near-eye display system according to claim 2, wherein: The front optical surface of the second prism is coated with a semi-transparent and semi-reflective optical film, and its reflectivity r_C1 satisfies 5%<r_C1<90%; The diopter of the compensation lens is set to offset the horizontal light transmission diopter of the combination of the first prism, the second prism and the third prism; The fast axis of the first quarter wave plate forms an angle of 45° with the light axis of the polarization splitting film; In the first prism, the angle between the optical axis of the inclined optical surface and the normal of the vertical optical surface is 45° to 65°; In the first prism, the angle between the cemented surface and the vertical optical surface is 20° to 35°; The optical axis of the rear concave optical surface of the third prism coincides with the normal of the vertical optical surface of the first prism; the optical axis of the rear concave optical surface of the third prism coincides with the optical axis of the front optical surface of the second prism.

5. The combined prism-type reentrant near-eye display system according to any one of claims 1 to 4, characterized in that: The air gap between the first quarter-wave plate and the vertical optical surface of the first prism is greater than 0.01 mm; The compensation lens is a dark lens.

6. The combined prism-type reentrant near-eye display system according to any one of claims 1 to 4, characterized in that: The inclined optical surface of the first prism, the front optical surface of the second prism and the rear concave optical surface of the third prism are all spherical or aspherical surfaces; The inclined optical surface of the first prism, the vertical optical surface of the first prism, and the rear concave optical surface of the third prism are all coated with an anti-reflection film.

7. The combined prism-type reentrant near-eye display system according to any one of claims 1 to 4, characterized in that: The bottom light-absorbing surface at the bottom end of the third prism is a frosted surface or a black surface.

8. The combined prism-type reentrant near-eye display system according to any one of claims 1 to 4, characterized in that: Positioning grooves are provided on both sides of the first prism, the second prism and the third prism. When the positioning grooves of the first prism, the second prism and the third prism overlap, they are assembled into a preset optical position; The micro display screen adopts any one of a Micro-OLED screen, a Micro-LED screen, an LCD screen, and an original image LBS light source.

9. The combined prism-type reentrant near-eye display system according to claim 8, characterized in that: The positioning groove is a V-shaped positioning groove or an arc-shaped positioning groove.

10. AR glasses, comprising: A glasses body and a near-eye display system integrated on the glasses body, characterized in that the near-eye display system adopts the combined prism-type reentrant near-eye display system described in any one of claims 1-9.

Images