Thinned large FOV optical display system and wearable device

Abstract

The utility model provides a thinned large FOV optical display system and wearable equipment, belongs to the optical imaging technology field, and comprises a display unit, a transmitting mirror, a first prism, a second prism and a compensating mirror, the transmitting mirror is arranged on a light-emitting light path of the display unit, the first prism is arranged on a transmitting light path of the transmitting mirror, and the second prism is arranged on a light-emitting light path of the compensating mirror. A partial transmission and partial reflection film is arranged on the front surface of the first prism, the second prism is arranged on the rear side of the first prism, a phase delay film, a polarization reflection film and an absorption film are sequentially arranged between the first prism and the second prism, and the compensating mirror is arranged on the front side of the first prism; and one part of the light transmitted from the transmitting mirror enters the first prism from the upper surface of the first prism, and the other part of the light enters the compensating mirror from the upper surface of the compensating mirror and then enters the first prism. The optical system is compact in structure, small in size, light in weight, thin in thickness, low in stray, high in light utilization rate, good in imaging quality and large in field angle, and greatly improves user experience.

Description

Technical Field

[0001] The utility model belongs to the technical field of optical imaging, and in particular relates to a thinned large FOV optical display system and a wearable device. Background Art

[0002] Enhanced display optical display technology is a technology that can project and magnify the display image. This technology can not only expand the traditional display technology, but also introduce a new experience: integrating the real world with the virtual world, making people's lives more convenient and enriching their entertainment. It has been widely used in education, medical care, aerospace and other fields.

[0003] In the rapid development of augmented reality optical display technology, many different technical solutions have emerged, including Birdbath, array optical waveguide, diffraction optical waveguide, etc. However, the existing module solutions of these technologies are relatively large in size for greater performance. Utility Model Content

[0004] The purpose of the implementation mode of the utility model is to provide a thinned large FOV optical display system, which has a small size, light weight, thin thickness, low stray light, high light utilization rate, good imaging quality, and a large field of view, thereby greatly improving the user experience.

[0005] Another object of the embodiments of the present invention is to provide a head mounted display device which is light in weight and easy to wear.

[0006] The implementation mode of the utility model is achieved as follows:

[0007] The embodiment of the utility model provides a thinned large FOV optical display system, comprising a display unit, a transmission mirror, a first prism, a second prism and a compensation mirror.

[0008] The transmission mirror is arranged on the light output path of the display unit, the first prism is arranged on the light path of the transmission light of the transmission mirror, the upper surface of the first prism faces the transmission mirror, the rear surface of the first prism faces the human eye, the front surface of the first prism is provided with a partially transmission and partially reflection film, the second prism is arranged on the rear side of the first prism, a phase delay film, a polarization reflection film and an absorption film are arranged between the first prism and the second prism in sequence, the phase delay film is attached to the rear surface of the first prism, the compensation mirror is arranged on the front side of the first prism, and the upper surface of the compensation mirror also faces the transmission mirror;

[0009] A portion of the light transmitted from the transmission mirror is incident on the first prism from the upper surface of the first prism and enters the first prism, and the rest of the light is first incident on the compensation mirror from the upper surface of the compensation mirror, then transmitted from the rear surface of the compensation mirror and incident on the first prism from the front surface of the first prism and enters the first prism.

[0010] Optionally, an incident angle of light incident from the upper surface of the first prism into the first prism is α, and 0<α<50°.

[0011] Optionally, the incident angle of the light entering the compensation mirror from the upper surface of the compensation mirror is β, and 50°<β<90°.

[0012] Optionally, the partially transmissive and partially reflective film is used to reflect light with an incident angle less than 50°, and to transmit light with an incident angle greater than 60°.

[0013] Optionally, the rear surface of the first prism is an inclined surface inclined downward from back to front, the front surface of the second prism is an inclined surface inclined downward from back to front, the rear surface of the first prism corresponds to the front surface of the second prism, and the rear surface of the second prism faces the human eye.

[0014] Optionally, the radius of curvature of the front surface of the first prism is R1, |R1|<100 mm, and the radius of curvature of the rear surface of the compensation mirror is R2, |R2|<100 mm.

[0015] Optionally, a light absorbing film layer is provided on the lower surface of the second prism.

[0016] Optionally, the rear surface of the compensation mirror is tightly fitted to the front surface of the first prism or there is a gap therebetween.

[0017] Optionally, the upper surface, front surface and rear surface of the first prism are spherical, aspherical, free-form or Fresnel surfaces, and the upper surface, lower surface and rear surface of the second prism are spherical, aspherical, free-form or Fresnel surfaces.

[0018] An embodiment of the utility model further provides a wearable device, comprising a wearable component and the thinned large FOV optical display system described above, wherein the optical display system is arranged on the wearable component.

[0019] The beneficial effects of the utility model are:

[0020] The optical display system for improving optical display performance provided by the embodiment of the utility model has a compact structure, small size, light weight, thin thickness, low stray light, high light utilization rate, good imaging quality, and a large field of view, which greatly improves the user experience.

[0021] The wearable device provided by the embodiment of the utility model has a simple production process, low cost, light weight, and is easy to wear, which greatly improves the wearing experience of the user. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments are briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

[0023] Figure 1 This is a diagram of the architecture of a thinned large FOV optical display system according to Embodiment 1;

[0024] In the figure: 1-display unit; 2-transmitting mirror; 3-first prism; 31-partially transmitting and partially reflecting film; 32-phase delay film; 33-polarized reflecting film; 34-absorbing film; 4-second prism; 5-compensating mirror. DETAILED DESCRIPTION

[0025] In order to make the purpose, technical scheme and advantages of the embodiments of the present invention clearer, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. The components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0026] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present invention.

[0027] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features thereof may be combined with each other.

[0028] In the description of the present utility model, it should be noted that the terms "inside", "outside", "front", "back", "upper", "lower", etc. indicate the orientation or position relationship based on the orientation or position relationship shown in the drawings, or the orientation or position relationship in which the utility model product is usually placed when in use, or the orientation or position relationship commonly understood by those skilled in the art, which is only for the convenience of describing the present utility model and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present utility model. In addition, the terms "first", "second", "third", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance. Example 1

[0029] refer to Figure 1 As shown, the first embodiment of the utility model provides a thinned large FOV optical display system, including a display unit 1, a transmission mirror 2, a first prism 3, a second prism 4 and a compensation mirror 5.

[0030] The display unit 1 mainly plays the role of emitting light. The display unit 1 can display 2D or 3D images or videos, etc. The display unit 1 can adopt an OLED display, an LCD display, an LCOS display, a micro-LED display or a mini-LED display, etc.

[0031] The transmission mirror 2 is arranged on the light path of the display unit 1. The transmission mirror 2 is used to control the light, improve image quality parameters such as image distortion and resolution, and reduce the system volume. The number of the transmission mirror 2 can be only one, or two or more.

[0032] The material of the transmission mirror 2 can be plastic or glass. The two side surfaces of the transmission mirror 2 can be processed into spherical surface, aspherical surface, free-form surface or Fresnel surface.

[0033] The first prism 3 is a triangular prism structure, which can be made into a solid prism structure or a hollow prism structure. When it is made into a hollow prism structure, its interior is filled with optical liquid or gas. The first prism 3 is arranged on the transmission light path of the transmission mirror 2, the upper surface of the first prism 3 faces the transmission mirror 2, the rear surface of the first prism 3 faces the human eye, and the rear surface of the first prism 3 is an inclined surface obliquely downward from the back to the front. The front surface of the first prism 3 is provided with a partially transmissive and partially reflective film 31, and the partially transmissive and partially reflective film 31 is used to reflect light with an incident angle less than 50° and transmit light with an incident angle greater than 60°.

[0034] The upper surface, the front surface and the rear surface of the first prism 3 are spherical surfaces, aspherical surfaces, free-form surfaces or Fresnel surfaces, and are processed as required.

[0035] The second prism 4 is a prism-like structure, which can be made into a solid prism structure or a hollow prism structure. When it is made into a hollow prism structure, its interior is filled with optical liquid or gas. The second prism 4 is arranged below the rear side of the first prism 3, and the front surface of the second prism 4 is an inclined surface that is inclined downward from the back to the front; the front surface of the second prism 4 corresponds to the rear surface of the first prism 3, the rear surface of the second prism 4 faces the human eye, and the lower surface of the second prism 4 faces downward, and the lower surface of the second prism 4 is provided with a light-absorbing film layer.

[0036] The upper surface, the front surface and the rear surface of the second prism 4 are spherical surfaces, aspherical surfaces, free-form surfaces or Fresnel surfaces, and are processed as required.

[0037] A phase delay film 32, a polarization reflection film 33 and an absorption film 34 are sequentially arranged between the first prism 3 and the second prism 4. The phase delay film is attached to the rear surface of the first prism 3, and the absorption film 34 is attached to the front surface of the second prism 4. The phase delay film 32 is used to change the polarization characteristics of the light. The polarization reflection film 33 is used to reflect the light of a certain normal state. The absorption film 34 is used to absorb external stray light.

[0038] The compensating mirror 5 is arranged in front of the first prism 3, and the rear surface of the compensating mirror 5 is closely fitted with the front surface of the first prism 3. Of course, there may be a certain gap between the two, and the upper surface of the compensating mirror 5 also faces the transmission mirror 2. The compensating mirror 5 is used to allow the user to see the external environment.

[0039] The radius of curvature of the front surface of the first prism 3 is R1, |R1|<100 mm, and the radius of curvature of the rear surface of the compensation mirror 5 is R2, |R2|<100 mm.

[0040] Part of the light transmitted from the transmission mirror 2 is incident from the upper surface of the first prism 3 into the first prism 3, propagates toward the rear surface of the first prism 3, is reflected for the first time at the polarized reflection film, and the light after the first reflection propagates toward the front surface of the first prism 3, and then is reflected for the second time at the front surface. The light reflected for the second time passes through the rear surface of the first prism 3, the phase delay film 32, the polarized reflection film 33, and the absorption film 34 in sequence, and then enters the second prism 4 from the front surface of the second prism 4, and finally transmits from the rear surface of the second prism 4 to reach the human eye, forming a virtual image with a specific magnification; the rest of the light is transmitted from the compensation mirror 5 The upper surface first enters the compensation mirror 5, then is transmitted from the rear surface of the compensation mirror 5 and is incident from the front surface of the first prism 3 into the inside of the first prism 3, propagates toward the rear surface of the first prism 3, is reflected for the first time at the polarized reflection film, and the light after the first reflection propagates toward the front surface of the first prism 3, and then is reflected for the second time at the front surface. The light reflected for the second time passes through the rear surface of the first prism 3, the phase delay film 32, the polarized reflection film 33, and the absorption film 34 in sequence, and then enters the second prism 4 from the front surface of the second prism 4, and finally is transmitted from the rear surface of the second prism 4 to reach the human eye, forming a virtual image with a specific magnification.

[0041] In this embodiment, the incident angle of the light entering the first prism 3 from the upper surface of the first prism 3 is α, 0<α<50°. The incident angle of the light entering the compensation mirror 5 from the upper surface of the compensation mirror 5 is β, 50°<β<90°. Example 2

[0042] A second embodiment of the present invention provides a wearable device, including a wearable component and an optical display system.

[0043] It should be noted that the optical display system in this embodiment can adopt the optical display system in Example 1. Its structure, working principle and technical effects produced refer to the corresponding contents in Example 1 and are not described in detail here.

[0044] The optical display system is set on the wearable component. The wearable component can be a helmet or a glasses frame, etc., which is convenient for people to wear on their heads. Of course, the head-mounted display device also includes a control unit, a storage unit, etc. The control unit is used to control the device, and the storage unit is used to store images, videos, etc.

[0045] It should be noted that the present application does not limit the application of the optical display system to a head-mounted display device. The system can also be applied to other devices. In one possible application scenario, it can also be integrated with a desktop-level optical display device and a vehicle-mounted optical display device. The virtual image distance is farther, which can realize the eye protection function and enhance the viewing experience.

[0046] The utility model is not limited to the above optional implementation modes, and anyone can derive other various forms of products under the enlightenment of the utility model. The above specific implementation modes should not be understood as limiting the protection scope of the utility model. The protection scope of the utility model shall be based on the definition in the claims, and the description can be used to interpret the claims.

Claims

1. A thinned large FOV optical display system, characterized in that: The invention comprises a display unit, a transmission mirror, a first prism, a second prism and a compensation mirror, The transmission mirror is arranged on the light output path of the display unit, the first prism is arranged on the light output path of the transmission light of the transmission mirror, the upper surface of the first prism faces the transmission mirror, the rear surface of the first prism faces the human eye, the front surface of the first prism is provided with a partially transmission and partially reflection film, the second prism is arranged on the rear side of the first prism, a phase delay film, a polarization reflection film and an absorption film are arranged between the first prism and the second prism in sequence, the phase delay film is attached to the rear surface of the first prism, the compensation mirror is arranged on the front side of the first prism, and the upper surface of the compensation mirror also faces the transmission mirror; A portion of the light transmitted from the transmission mirror is incident on the first prism from the upper surface of the first prism and enters the first prism, and the rest of the light is first incident on the compensation mirror from the upper surface of the compensation mirror, then transmitted from the rear surface of the compensation mirror and incident on the first prism from the front surface of the first prism and enters the first prism.

2. The thinned large FOV optical display system according to claim 1, characterized in that: The incident angle of the light entering the first prism from the upper surface of the first prism is α, and 0<α<50°.

3. The thinned large FOV optical display system according to claim 1, characterized in that: The incident angle of the light entering the compensation mirror from the upper surface of the compensation mirror is β, 50°<β<90°.

4. The thinned large FOV optical display system according to claim 1, characterized in that: The partially transmissive and partially reflective film is used to reflect light with an incident angle less than 50° and transmit light with an incident angle greater than 60°.

5. The thinned large FOV optical display system according to claim 1, characterized in that: The rear surface of the first prism is an inclined surface inclined downward from the back to the front, the front surface of the second prism is an inclined surface inclined downward from the back to the front, the rear surface of the first prism corresponds to the front surface of the second prism, and the rear surface of the second prism faces the human eye.

6. The thinned large FOV optical display system according to claim 1, characterized in that: The curvature radius of the front surface of the first prism is R1, |R1|<100mm, and the curvature radius of the rear surface of the compensation mirror is R2, |R2|<100mm.

7. The thinned large FOV optical display system according to claim 1, characterized in that: A light absorbing film layer is disposed on the lower surface of the second prism.

8. The thinned large FOV optical display system according to claim 1, characterized in that: The rear surface of the compensation mirror is closely attached to the front surface of the first prism or there is a gap therebetween.

9. The thinned large FOV optical display system according to claim 1, characterized in that: The upper surface, front surface and rear surface of the first prism are spherical, aspherical, free-form or Fresnel surfaces, and the upper surface, lower surface and rear surface of the second prism are spherical, aspherical, free-form or Fresnel surfaces.

10. A wearable device, characterized in that: It comprises a wearable component and a thinned large FOV optical display system as described in any one of claims 1 to 9, wherein the optical display system is arranged on the wearable component.

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