A four-reflection, thin, wide-field-of-view near-eye display system

Abstract

This utility model discloses a four-reflection, thin, wide-field-of-view near-eye display system, comprising an image source, a first prism, a second prism, and a first lens. The second prism has a first surface, a second surface, and a third surface. The first prism, the first lens, and the image source are sequentially disposed on the sides of the first, second, and third surfaces of the second prism. A first film layer is also disposed between the first and second prisms, and a first included angle between the first and second prisms is appropriately set. Light emitted from the image source passes through the third surface to the first surface, and after being reflected sequentially by the first and second surfaces, it passes through the first surface to the first film layer. It is then reflected by the first film layer and sequentially passes through the second prism and the first lens. Finally, it is reflected by a mirror surface on the first lens away from the second prism and sequentially passes through the first lens, the second prism, the first film layer, and the first prism before entering the human eye. This system achieves high imaging quality while being thinner and lighter, and has a wider field of view.

Description

Technical Field

[0001] This utility model belongs to the field of near-eye display technology, specifically relating to a four-reflection type thin and light large field of view near-eye display system. Background Technology

[0002] AR display technology, or virtual reality display technology, uses optical elements to overlay virtual and real images. Currently, optical devices for AR display technology can be broadly classified into two types. One type uses a projection optical engine to project projection light onto an optical waveguide, where it undergoes total internal reflection before being output to the human eye. Simultaneously, ambient light can also be projected onto the human eye through the waveguide, thus achieving an overlay of virtual and real images. The other type uses geometric optical elements to transmit projection light to the human eye, while ambient light can also be projected onto the human eye through these elements, achieving a virtual reality overlay display.

[0003] Optical waveguide solutions currently suffer from limitations in display quality and user experience due to issues with optical engine resolution and waveguide manufacturing processes. Existing geometric imaging optical solutions offer better display performance, but achieving a large field of view while maintaining a comfortable eye distance necessitates a larger aperture and optical engine size, making it difficult to achieve a thin and lightweight design. Therefore, given the current demand for thin and lightweight AR glasses, maintaining both a small optical engine size and a large field of view (FOV) is a crucial challenge that must be addressed. Utility Model Content

[0004] The purpose of this invention is to address the above-mentioned problems by proposing a four-reflection, thin, light-weight, large-field-of-view near-eye display system that achieves both high imaging quality and a thin and light weight with a large field of view.

[0005] To achieve the above objectives, the technical solution adopted by this utility model is as follows:

[0006] This utility model proposes a four-reflection type thin and light large field of view near-eye display system, including an image source, a first prism, a second prism, and a first lens, wherein:

[0007] The second prism has a first surface, a second surface, and a third surface. The first prism, the first lens, and the image source are sequentially disposed on the sides of the first, second, and third surfaces of the second prism. A first film layer is also disposed between the first and second prisms, and satisfies the following conditions: , The first included angle of the first prism The first angle of the second prism is the angle between the surface near the second prism and the surface near the human eye. The angle between the first surface and the second surface;

[0008] The light emitted from the image source passes through the third surface to the first surface, and is reflected in sequence by the first and second surfaces. It then passes through the first surface to the first film layer, is reflected by the first film layer, and passes in sequence through the second prism and the first lens. Finally, it is reflected by the mirror surface on the first lens that is far from the second prism and passes in sequence through the first lens, the second prism, the first film layer, and the first prism before entering the human eye.

[0009] Preferably, the first included angle of the first prism The first angle between the second prism and the second prism All are between 13° and 25°.

[0010] Preferably, the focal length of the four-reflection, thin, wide-field-of-view near-eye display system is 14mm-20mm.

[0011] Preferably, the first film layer includes an absorptive polarizing film and a reflective polarizing film arranged sequentially along the direction away from the human eye, and a second film layer is also provided between the second prism and the first lens, the second film layer being a 1 / 4 wave plate;

[0012] Alternatively, the first film layer may include an absorptive polarizing film, a reflective polarizing film, and a quarter-wave plate arranged sequentially in a direction away from the human eye;

[0013] Alternatively, the first membrane layer may be a semi-permeable and semi-reflective membrane, and the permeability-to-reflection ratio of the semi-permeable and semi-reflective membrane may be 3:7 to 7:3.

[0014] Preferably, the four-reflection thin and light large field of view near-eye display system further includes a second lens located between the image source and the second prism. The mirror surface of the second lens near the second prism is convex and has a radius of curvature greater than or equal to 10 mm, while the mirror surface away from the second prism has a radius of curvature less than or equal to -100 mm or greater than or equal to 100 mm. The refractive index of the second lens is 1.5-1.9, the Abbe number is 23-80, and the thickness is 0.5 mm-4.5 mm.

[0015] Preferably, the four-reflection thin and light large field of view near-eye display system further includes a third film layer, which is an absorptive polarizing film or a quarter-wave plate, or is composed of an absorptive polarizing film and a quarter-wave plate arranged sequentially along the direction away from the image source, and the third film layer is arranged close to the light-emitting side of the image source.

[0016] Preferably, the mirror surface of the first lens away from the second prism is provided with a semi-transparent and semi-reflective film, and the transmission-to-reflection ratio of the semi-transparent and semi-reflective film is 3:7 to 7:3.

[0017] Preferably, the four-reflection thin and light large field of view near-eye display system further includes a third lens located on the side of the first prism closer to the human eye. The radius of curvature of the mirror surface of the third lens closer to the human eye is less than or equal to -100mm or greater than or equal to 100mm, and the radius of curvature of the mirror surface farther from the human eye is less than or equal to -100mm or greater than or equal to 100mm. The refractive index of the third lens is 1.5-1.9, the Abbe number is 23-80, and the thickness is 0.5mm-4.0mm.

[0018] Preferably, the four-reflection thin and light large field of view near-eye display system further includes a fourth lens located on the side of the first lens away from the human eye. The mirror surface of the fourth lens that is close to the human eye has the same shape and opposite direction as the mirror surface of the first lens that is far from the second prism. The mirror surface of the fourth lens that is far from the human eye has the same shape and opposite direction as the mirror surface of the first lens that is close to the second prism.

[0019] Preferably, the radius of curvature of the mirror surface of the first lens away from the second prism is 35mm-70mm, the radius of curvature of the mirror surface near the second prism is less than or equal to -100mm or greater than or equal to 100mm, and the refractive index is 1.5-1.9, the Abbe number is 35-70, and the thickness is 2.5mm-4.5mm.

[0020] Preferably, the surface of the first prism closest to the human eye is convex or concave, and the radius of curvature is less than or equal to -100 mm or greater than or equal to 100 mm.

[0021] Preferably, the moving distance of the image source is less than or equal to 2.0 mm, thereby achieving diopter adjustment from 1D to -7D.

[0022] Preferably, the first prism and the second prism are made of the same material, and have a refractive index of 1.5-1.8 and an Abbe number of 23-60.

[0023] Compared with the prior art, the beneficial effects of this utility model are as follows:

[0024] This application utilizes four reflections of light between a prism and a lens to ensure a large field of view and good image quality, while also helping to reduce the size of the optical mechanism while maintaining the same optical path length. This results in a lightweight and thinner overall structure with high light utilization efficiency. Specifically, four folded reflections replace the axial optical path, shortening the axial thickness of the imaging system and thus achieving a lightweight overall design. Furthermore, by rationally setting the focal length of the entire optical system, a large field of view (FOV) is ensured, resulting in high overall light utilization efficiency along the propagation path. Specifically, it achieves a field of view (FOV) greater than 48°, an overall optical thickness of less than 9mm, an eye-to-eye distance greater than 15mm, and an eyebox size of 11mm. With a 7mm thickness, the display effect maintains a full field of view of greater than 0.38 at 1 / 4 Nyq (1 / 4 extreme resolution), demonstrating significant overall performance advantages. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of the structure of Scheme 1 of the four-reflection thin and light large field of view near-eye display system of the present invention;

[0026] Figure 2 This is the MTF diagram of Scheme 1 of the present invention;

[0027] Figure 3 This is the defocused MTF diagram of Scheme 1 of the present invention;

[0028] Figure 4 This is the field distortion diagram of Scheme 1 of the present invention;

[0029] Figure 5 This is a dot diagram of Scheme 1 of the present invention;

[0030] Figure 6 This is a schematic diagram of the second scheme of the four-reflection thin and light large field of view near-eye display system of the present invention;

[0031] Figure 7 This is a schematic diagram of the third scheme of the four-reflection thin and light large field of view near-eye display system of the present invention;

[0032] Figure 8 This is a schematic diagram of the fourth scheme of the four-reflection thin and light large field of view near-eye display system of the present invention;

[0033] Figure 9 This is a schematic diagram of the fifth scheme of the four-reflection thin and light large field of view near-eye display system of the present invention;

[0034] Figure 10 This is a schematic diagram of the sixth scheme of the four-reflection thin and light large field of view near-eye display system of the present invention;

[0035] Figure 11 This is a schematic diagram of the structure of Scheme 7 of the four-reflection thin and light large field of view near-eye display system of the present invention.

[0036] Explanation of reference numerals in the attached figures: 1. Image source; 2. First prism; 3. Second prism; 4. First lens; 5. First film layer; 6. Second film layer; 7. Second lens; 8. Third film layer; 9. Third lens; 10. Fourth lens; STOP, aperture stop. Detailed Implementation

[0037] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0038] It should be noted that, unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of the application.

[0039] like Figures 1-11 As shown, a four-reflection, thin, wide-field-of-view near-eye display system includes an image source 1, a first prism 2, a second prism 3, and a first lens 4, wherein:

[0040] The second prism 3 has a first surface, a second surface, and a third surface. The first prism 2, the first lens 4, and the image source 1 are sequentially disposed on the sides of the first, second, and third surfaces of the second prism 3. A first film layer 5 is also disposed between the first prism 2 and the second prism 3, and satisfies the following conditions: , The first included angle of the first prism 2 The first included angle of the second prism 3 is the angle between the surface near the second prism 3 and the surface near the human eye. The angle between the first surface and the second surface;

[0041] The light emitted from image source 1 passes through the third surface to the first surface, and is reflected in sequence by the first and second surfaces. It then passes through the first surface to the first film layer 5, is reflected by the first film layer 5, and passes in sequence through the second prism 3 and the first lens 4. Finally, it is reflected by the mirror surface of the first lens 4 that is away from the second prism 3 and passes in sequence through the first lens 4, the second prism 3, the first film layer 5, and the first prism 2 before entering the human eye.

[0042] Among them, such as Figure 7 As shown, image source 1 is preferably a Micro OLED display, Micro LED display, or LCD display, and can be adjusted according to actual needs. Preferably, the angle between the emitted light from image source 1 and the perpendicular plane of the first surface of the second prism is greater than the total internal reflection angle. The first angle of the first prism 2... That is, the angle between the surface of the first prism 2 near the second prism 3 and the surface near the human eye, and the first angle of the second prism 3. This refers to the angle between the first and second surfaces of the second prism 3. The first reflection occurs on the first surface, preferably total internal reflection (the reflection angle of the light reaching the first and second surfaces of the second prism is greater than the total internal reflection angle), or reflection can also be achieved on the first surface when the reflective polarizing film of the first film layer 5 is large enough and attached to the first surface. The second reflection occurs on the second surface, preferably total internal reflection. The third reflection also passes through the first surface, preferably using the reflective polarizing film of the first film layer 5. The reflection reaching the first lens 4 is preferably a semi-transparent, semi-reflective film. By appropriately setting the first angle of the first prism 2... The first angle between the second prism 3 and the first angle between the two prisms 3 The prism achieves four-fold reflection to replace the axial optical path, thereby shortening the axial thickness of the imaging system and making the overall design thinner and lighter. It also helps to ensure that the optical system has a large field of view (FOV). In addition, the overall light utilization efficiency is high after the light passes through multiple film layers in the propagation path.

[0043] In one embodiment, the first included angle of the first prism 2 The first angle between the second prism 3 and the second prism 3 All are between 13° and 25°.

[0044] In one embodiment, the focal length of the four-reflection, thin, wide-field-of-view near-eye display system is 14mm-20mm. The focal length of the entire optical system is preferably 16mm-17mm, which helps ensure a large FOV for the optical system.

[0045] In one embodiment, the first film layer 5 includes an absorptive polarizing film and a reflective polarizing film arranged sequentially along the direction away from the human eye, and a second film layer 6 is also provided between the second prism 3 and the first lens 4, the second film layer 6 being a 1 / 4 wave plate;

[0046] Alternatively, the first film layer 5 may include an absorptive polarizing film, a reflective polarizing film, and a quarter-wave plate arranged sequentially along the direction away from the human eye;

[0047] Alternatively, the first membrane layer 5 may be a semi-permeable and semi-reflective membrane, and the permeability-to-reflection ratio of the semi-permeable and semi-reflective membrane may be 3:7 to 7:3.

[0048] The film layer configuration includes three schemes. The first scheme is preferred, where the first film layer 5 includes an absorptive polarizing film and a reflective polarizing film arranged sequentially along the direction away from the human eye, and a second film layer 6 is set between the second prism 3 and the first lens 4 as a quarter-wave plate. The second scheme includes the first film layer 5 including an absorptive polarizing film, a reflective polarizing film, and a quarter-wave plate arranged sequentially along the direction away from the human eye, without the second film layer 6. The third scheme is that the first film layer 5 is a semi-transparent, semi-reflective film, without the second film layer 6. There are many ways to combine film materials in this application, which will not be elaborated upon here. The purpose is to achieve four-fold reflection, and those skilled in the art can adjust it according to actual needs.

[0049] In one embodiment, the four-reflection thin and light large field-of-view near-eye display system further includes a second lens 7 located between the image source 1 and the second prism 3. The mirror surface of the second lens 7 near the second prism 3 is convex with a radius of curvature greater than or equal to 10 mm, while the mirror surface away from the second prism 3 has a radius of curvature less than or equal to -100 mm or greater than or equal to 100 mm. The second lens 7 has a refractive index of 1.5-1.9, an Abbe number of 23-80, and a thickness of 0.5 mm-4.5 mm. Figure 6 As shown, the second lens 7 helps to improve image quality.

[0050] In one embodiment, the four-reflection thin and light large field-of-view near-eye display system further includes a third film layer 8. The third film layer 8 is an absorptive polarizing film or a quarter-wave plate, or is composed of an absorptive polarizing film and a quarter-wave plate arranged sequentially along a direction away from the image source 1, and the third film layer 8 is disposed close to the light-emitting side of the image source 1. If a second lens 7 is present, the third film layer 8 is disposed close to the light-emitting side of the image source 1, that is, between the image source 1 and the second lens 7.

[0051] In one embodiment, the mirror surface of the first lens 4 away from the second prism 3 is provided with a semi-transparent and semi-reflective film, and the transmission-to-reflection ratio of the semi-transparent and semi-reflective film is 3:7 to 7:3.

[0052] The third film layer 8 may be omitted. When included, it can be used in combination with the aforementioned film materials. For example, the third film layer 8 may consist of an absorptive polarizing film and a quarter-wave plate arranged sequentially along the direction away from the image source 1. The first film layer 5 may include an absorptive polarizing film, a reflective polarizing film, and a quarter-wave plate arranged sequentially along the direction away from the human eye, without the second film layer 6. Alternatively, the first film layer 5 may be a semi-transparent and semi-reflective film (transmission-to-reflection ratio of 3:7 to 7:3), and the third film layer 8 may be a quarter-wave plate or consist of an absorptive polarizing film and a quarter-wave plate arranged sequentially along the direction away from the image source 1, without the second film layer 6. The third film layer 8 can filter out stray light before the light source enters the second lens 7, resulting in a cleaner overall optical-mechanical imaging.

[0053] In one embodiment, the four-reflection thin and light large field-of-view near-eye display system further includes a third lens 9 located on the side of the first prism 2 closest to the human eye. The radius of curvature of the mirror surface of the third lens 9 closest to the human eye is less than or equal to -100mm or greater than or equal to 100mm, and the radius of curvature of the mirror surface furthest from the human eye is less than or equal to -100mm or greater than or equal to 100mm. The refractive index of the third lens 9 is 1.5-1.9, the Abbe number is 23-80, and the thickness is 0.5mm-4.0mm. Figure 9 As shown, the third lens 9 helps to expand the field of view (FOV) while reducing the aperture of the first lens 4, thereby reducing the overall size of the optical engine and making the whole structure have a large field of view while achieving a thinner and lighter design; the refractive power range of the third lens 9 is -2D to 2D.

[0054] In one embodiment, the four-reflection thin and light large field-of-view near-eye display system further includes a fourth lens 10 located on the side of the first lens 4 away from the human eye. The mirror surface of the fourth lens 10 near the human eye has the same shape but opposite direction to the mirror surface of the first lens 4 away from the second prism 3. The mirror surface of the fourth lens 10 away from the human eye has the same shape but opposite direction to the mirror surface of the first lens 4 near the second prism 3. Figure 11 As shown, by adding a fourth lens 10 to compensate for the curvature of the human eye when looking at the outside world through the first lens 4, the human eye can see the outside world normally without distortion. The surface shape and radius of curvature of the fourth lens 10 are mainly determined by the shape of the first lens 4. Generally speaking, the surface shape and radius of curvature of the adjacent surfaces of the fourth lens 10 and the first lens 4, as well as the opposite surfaces, are the same but in opposite directions.

[0055] In one embodiment, the radius of curvature of the mirror surface of the first lens 4 furthest from the second prism 3 is 35mm-70mm, and the radius of curvature of the mirror surface closest to the second prism 3 is less than or equal to -100mm or greater than or equal to 100mm. The refractive index is 1.5-1.9, the Abbe number is 35-70, and the thickness is 2.5mm-4.5mm. The first lens 4 is the main contributing lens to the refractive power of the near-eye display system. The radius of curvature of the first lens 4, 35mm-70mm, ensures the matching of the refractive power and field of view of the near-eye display system. Simultaneously, it ensures that the near-eye display system has a certain optical path length to achieve back-and-forth folding space, avoiding situations where the optical path is too short to achieve back-and-forth folding or too long, resulting in an excessively large optical engine size. This helps to improve image quality while maintaining a thin and light design.

[0056] In one embodiment, the surface of the first prism 2 near the human eye is convex or concave, and its radius of curvature is less than or equal to -100 mm or greater than or equal to 100 mm. For example, Figure 8 As shown, the surface of the first prism 2 closest to the human eye can be spherical, aspherical, freeform, etc., preferably spherical. This makes it easier for the fourth lens 10 to correct the refractive power of the near-eye display system and avoids distortion when viewing the outside world.

[0057] In one embodiment, the image source 1 moves a distance of less than or equal to 2.0 mm, thereby achieving diopter adjustment from 1D to -7D. Figure 10 As shown, the dashed box represents the moved image source 1. The virtual image distance is adjusted by moving the position of the image source 1, i.e., diopter adjustment. For every 0.2mm movement in the light emission direction of the image source 1, 1D can be adjusted; the total adjustment range is 1D to -7D, and the movement range is 1.6mm. Under the same diopter adjustment, the movement is smaller, which is beneficial to ensuring miniaturization.

[0058] In one embodiment, the first prism 2 and the second prism 3 are made of the same material, with a refractive index of 1.5-1.8 and an Abbe number of 23-60. Preferably, the first prism 2 and the second prism 3 are made of the same material, with a high refractive index to make the total internal reflection angle smaller and easier to achieve total internal reflection, and a low Abbe number to make the optical system have less chromatic aberration.

[0059] For ease of understanding, the following detailed description is provided through specific embodiments.

[0060] like Figure 1 As shown, the four-reflection, thin, wide-field-of-view near-eye display system of this embodiment includes an image source 1, a first prism 2, a second prism 3, a first lens 4, a first film layer 5, a second film layer 6, a second lens 7, and a third film layer 8. The first film layer 5 includes an absorptive polarizing film and a reflective polarizing film arranged sequentially along the direction away from the human eye. The second film layer 6 is located between the second prism 3 and the first lens 4 and is a quarter-wave plate. The third film layer 8 is located between the image source 1 and the second lens 7. The light propagation path during operation is as follows: the light emitted from the image source 1 passes through the third film layer 8, the second lens 7, and the third surface (P2_S3) of the second prism, and then reaches the first surface (P2_S1) of the second prism and the second surface (P2_S2) of the second prism. Since the reflection angle of the light reaching the first surface of the second prism and the second surface of the second prism is greater than the total internal reflection angle (determined by the refractive index of the second prism, the formula for calculating the total internal reflection angle is...), the light propagation path during operation is as follows: the light emitted from the image source 1 passes through the third film layer 8, the second lens 7, and the third surface (P2_S3) of the second prism, and then reaches the first surface (P2_S1) of the second prism and the second surface (P2_S2) of the second prism. ,in, For total reflection angle, (Refractive index of the second prism). All light rays undergo total internal reflection at the first and second surfaces of the second prism (corresponding to the first and second reflections). The second reflection reaches the first surface of the second prism, then reaches the first film layer 5, where 40% of the polarized light is reflected (third reflection). The light then passes through the second prism 3, the second film layer 6, and the first lens 4, reaching the mirror surface (L1_S2) on the first lens that is far from the second prism. The light then reflects 50% of the light from the mirror surface (L1_S2) on the first lens (fourth reflection), and then passes through the first lens 4, the second film layer 6, the second prism 3, the first film layer 5, and the first prism 2, reaching the aperture stop (i.e., the human eye). Because the light passes through two quarter-wave plates, the polarization direction changes, allowing the light to pass completely through the first film layer 5, forming a virtual image with a virtual image distance greater than 2000mm.

[0061] The optical parameters of this embodiment are shown in Table 1 below. In Table 1, MIRROR represents reflection. S0 is the object plane, S1 is the stop, S2 and S3 correspond to the surfaces of the first prism 2 that are close to the human eye and away from the human eye, respectively. S4 is the surface of the first film layer 5 that is away from the first prism 2. The surface of the first film layer 5 that contacts the first prism 2 is not marked with a number, that is, the surface of the first film layer 5 that is close to the first prism 2 and the surface of the first prism 2 that contacts the first film layer 5 are considered as one surface. Similarly, S5 and S6 correspond to the first surface and the second surface of the second prism 3, respectively. S7 and S8 correspond to the surface of the second film layer 6 that is close to the second prism 3 and away from the second prism 3, respectively. S9 and S10 correspond to the surface of the first lens 4 that is close to the second prism 3 and away from the second prism 3, respectively. S11 and S13 are both... S14 is the second surface of the second prism 3, S17 is the first surface of the second prism 3 (mirror means reflection), S20 is the second surface of the second prism 3 (mirror means reflection), S23 is the first surface of the second prism 3 (mirror means reflection), S25 is the third surface of the second prism 3, S26 and S27 correspond to the surfaces of the second lens 7 that are close to the second prism 3 and far from the second prism 3, respectively, S28 is the surface of the protective glass of the image source 1 that is close to the second lens 7, S29 is the image plane, and S12, S15, S16, S18, S19, S21, S22 and S24 are all virtual surfaces used for tilting and eccentricity.

[0062] Table 1

[0063]

[0064] Based on the above parameters, and combined with Figures 2-5It can be seen that the MTF of this embodiment is high in each field of view (greater than 0.38 at 24 lp / mm); at the same time, the defocus curve convergence is also high (the virtual image distances of each field of view are relatively close); the distortion is small (less than 5% across the entire field of view); and the point spread function in the dot plot is small (less than 65 μm). This indicates that this embodiment maintains high imaging quality in all directions.

[0065] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0066] The embodiments described above are merely specific and detailed examples of the embodiments described in this application, and should not be construed as limiting the scope of the application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these modifications and improvements all fall within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the appended claims.

Claims

1. A lightweight, large-field-of-view near-eye display system with four-fold reflection, characterized in that: It includes an image source (1), a first prism (2), a second prism (3), and a first lens (4), wherein: The second prism (3) has a first surface, a second surface, and a third surface. The first prism (2), the first lens (4), and the image source (1) are sequentially disposed on the sides of the first surface, the second surface, and the third surface of the second prism (3). A first film layer (5) is also provided between the first prism (2) and the second prism (3), and satisfies the following conditions: , The first included angle of the first prism (2) The first angle of the second prism (3) is the angle between the surface near the second prism (3) and the surface near the human eye. The angle between the first surface and the second surface; The light emitted by the image source (1) passes through the third surface to the first surface, and after being reflected in sequence on the first surface and the second surface, it passes through the first surface to the first film layer (5), and is then reflected by the first film layer (5) and passes through the second prism (3) and the first lens (4) in sequence. After being reflected by the mirror surface of the first lens (4) away from the second prism (3), it passes through the first lens (4), the second prism (3), the first film layer (5) and the first prism (2) in sequence and enters the human eye.

2. The four-reflection, thin, wide-field-of-view near-eye display system as described in claim 1, characterized in that: The first included angle of the first prism (2) The first angle between the second prism (3) and the second prism (3) All are between 13° and 25°.

3. The four-reflection, thin, wide-field-of-view near-eye display system as described in claim 1, characterized in that: The focal length of the four-reflection, thin, wide-field-of-view near-eye display system is 14mm-20mm.

4. The four-reflection, thin, wide-field-of-view near-eye display system as described in claim 1, characterized in that: The first film layer (5) includes an absorptive polarizing film and a reflective polarizing film arranged sequentially along the direction away from the human eye, and a second film layer (6) is also provided between the second prism (3) and the first lens (4), the second film layer (6) being a 1 / 4 wave plate; Alternatively, the first film layer (5) may include an absorptive polarizing film, a reflective polarizing film, and a quarter-wave plate arranged sequentially along the direction away from the human eye; Alternatively, the first membrane layer (5) may be a semi-permeable and semi-reflective membrane, and the permeability-to-reflection ratio of the semi-permeable and semi-reflective membrane may be 3:7 to 7:

3.

5. The four-reflection, thin, wide-field-of-view near-eye display system as described in claim 1, characterized in that: The four-reflection thin and light large field of view near-eye display system also includes a second lens (7) located between the image source (1) and the second prism (3). The mirror surface of the second lens (7) near the second prism (3) is convex and has a radius of curvature greater than or equal to 10 mm. The radius of curvature of the mirror surface away from the second prism (3) is less than or equal to -100 mm or greater than or equal to 100 mm. The refractive index of the second lens (7) is 1.5-1.9, the Abbe number is 23-80, and the thickness is 0.5 mm-4.5 mm.

6. The four-reflection, thin, wide-field-of-view near-eye display system as described in any one of claims 1 to 5, characterized in that: The four-reflection thin and light large field of view near-eye display system also includes a third film layer (8), which is an absorptive polarizing film or a quarter wave plate or is composed of an absorptive polarizing film and a quarter wave plate arranged sequentially along the direction away from the image source (1), and the third film layer (8) is arranged close to the light-emitting side of the image source (1).

7. The four-reflection, thin, wide-field-of-view near-eye display system as described in claim 1, characterized in that: The mirror surface of the first lens (4) away from the second prism (3) is provided with a semi-transparent and semi-reflective film, and the transmission-to-reflection ratio of the semi-transparent and semi-reflective film is 3:7 to 7:

3.

8. The four-reflection, thin, wide-field-of-view near-eye display system as described in claim 1, characterized in that: The four-reflection thin and light large field of view near-eye display system also includes a third lens (9) located on the side of the first prism (2) closer to the human eye. The radius of curvature of the mirror surface of the third lens (9) closer to the human eye is less than or equal to -100mm or greater than or equal to 100mm, and the radius of curvature of the mirror surface farther from the human eye is less than or equal to -100mm or greater than or equal to 100mm. The refractive index of the third lens (9) is 1.5-1.9, the Abbe number is 23-80, and the thickness is 0.5mm-4.0mm.

9. The four-reflection, thin, wide-field-of-view near-eye display system as described in claim 1, characterized in that: The four-reflection thin and light large field of view near-eye display system also includes a fourth lens (10) located on the side of the first lens (4) away from the human eye. The mirror surface of the fourth lens (10) that is close to the human eye has the same shape and opposite direction as the mirror surface of the first lens (4) that is far away from the second prism (3). The mirror surface of the fourth lens (10) that is far away from the human eye has the same shape and opposite direction as the mirror surface of the first lens (4) that is close to the second prism (3).

10. The four-reflection, thin, wide-field-of-view near-eye display system as described in claim 1, characterized in that: The first lens (4) has a radius of curvature of 35mm-70mm on the surface away from the second prism (3), and a radius of curvature of less than or equal to -100mm or greater than or equal to 100mm on the surface close to the second prism (3). It also has a refractive index of 1.5-1.9, an Abbe number of 35-70, and a thickness of 2.5mm-4.5mm.

11. The four-reflection, thin, wide-field-of-view near-eye display system as described in claim 1, characterized in that: The surface of the first prism (2) near the human eye is convex or concave, and the radius of curvature is less than or equal to -100 mm or greater than or equal to 100 mm.

12. The four-reflection, thin, wide-field-of-view near-eye display system as described in claim 1, characterized in that: The moving distance of the image source (1) is less than or equal to 2.0 mm, thereby achieving diopter adjustment from 1D to -7D.

13. The four-reflection, thin, wide-field-of-view near-eye display system as described in claim 1, characterized in that: The first prism (2) and the second prism (3) are made of the same material and have a refractive index of 1.5-1.8 and an Abbe number of 23-60.

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