CN116794837A

CN116794837A - AR display system and head-mounted display device

Info

Publication number: CN116794837A
Application number: CN202310647276.8A
Authority: CN
Inventors: 许礼强; 鲁公涛
Original assignee: Goertek Optical Technology Co Ltd
Current assignee: Goertek Optical Technology Co Ltd
Priority date: 2023-05-31
Filing date: 2023-05-31
Publication date: 2023-09-22

Abstract

Embodiments of the present application disclose an AR display system and a head-mounted display device. The AR display system includes an illumination light source, a first prism group, a second prism group, a quarter wave plate, an LCOS chip and an optical waveguide; the illumination The light source is used to emit S-polarized light and P-polarized light; the first prism group is used to reflect the S-polarized light to the LCOS chip, and the LCOS chip is used to modulate the received S-polarized light into P-polarized light. , P polarized light is incident into the first coupling region and coupled out from the first coupling region; the 1/4 wave plate is disposed on a side of the second prism group away from the first prism group. On the other hand, the 1/4 wave plate is used to modulate the P polarized light emitted by the illumination light source into S polarized light, and the second prism group is used to reflect the S polarized light modulated by the 1/4 wave plate. To the LCOS chip, the LCOS chip is used to modulate the received S-polarized light into P-polarized light, and inject the P-polarized light into the second coupling-in region and couple it out from the second coupling-out region. .

Description

AR display system and head-mounted display device

Technical Field

The application belongs to the technical field of augmented reality, and particularly relates to an AR display system and a head-mounted display device.

Background

With advances in imaging technology, users are increasingly demanding an immersive experience. The head-mounted display device can liberate hands of people, reduce dependence on a screen, and create a better visual effect.

However, in the prior art, a display screen mainly matched with a AR (AugmentedReality) head-mounted display device based on a diffraction optical waveguide scheme is LCOS (LiquidCrystalonSilicon). The AR head-mounted display device adopting LCOS is passively illuminated, so that an optical module needs to be added to improve the imaging effect of the AR head-mounted display device, so that the volume of the whole AR display device is relatively large, which is not beneficial to miniaturization and light and thin design and is not beneficial to miniaturized design of AR glasses.

Accordingly, it is desirable to provide a structure that combines imaging quality with thinness.

Disclosure of Invention

The embodiment of the application aims to provide a novel technical scheme of an AR display system and a head-mounted display device.

According to a first aspect of an embodiment of the present application, there is provided an AR display system including an illumination light source, a first prism group, a second prism group, a 1/4 wave plate, an LCOS chip, and an optical waveguide;

the illumination light source is used for emitting S polarized light and P polarized light;

the optical waveguide is provided with a first coupling-in region, a second coupling-in region, a first coupling-out region and a second coupling-out region;

the first prism group is used for reflecting the S polarized light to the LCOS chip, the LCOS chip is used for modulating the received S polarized light into P polarized light, and the P polarized light enters the first coupling-in area and is coupled out from the first coupling-out area;

the 1/4 wave plate is arranged on one side, far away from the first prism group, of the second prism group, the 1/4 wave plate is used for modulating P polarized light emitted by the illumination light source into S polarized light, the second prism group is used for reflecting the S polarized light modulated by the 1/4 wave plate to the LCOS chip, and the LCOS chip is used for modulating the received S polarized light into P polarized light, injecting the P polarized light into the second coupling-in area and coupling out from the second coupling-out area.

Optionally, the first prism group includes a first prism and a second prism, and the second prism group includes a third prism and a fourth prism; wherein,,

the first prism and the fourth prism are symmetrically arranged, and the second prism and the third prism are symmetrically arranged.

Optionally, the second prism is fixedly connected with the third prism.

Optionally, a reflecting mirror is arranged on one side of the 1/4 wave plate away from the second prism group; or,

and a high-reflection film is arranged on one side of the 1/4 wave plate, which is far away from the second prism group.

Optionally, the LCOS chip includes a first chip and a second chip, where the first chip, the first prism group, and the first coupling-in area are sequentially disposed along a first axis, and the second chip, the second prism group, and the second coupling-in area are sequentially disposed along a second axis;

wherein the first axis is parallel to the second axis.

Optionally, a corner prism is disposed between the illumination light source and the first prism group, and the corner prism is used for injecting the light emitted by the illumination light source into the first prism group.

Optionally, the device further comprises a projection lens module, wherein the projection lens module is arranged between the optical waveguide and the LCOS chip.

Optionally, a polarizing device is disposed on a side of the optical waveguide near the LCOS chip, and the polarizing device is used for filtering stray light.

Optionally, a phase retarder is disposed on a side of the LCOS chip adjacent to the optical waveguide.

According to a second aspect of an embodiment of the present application, there is also provided a head-mounted display device, including the AR display system of the first aspect.

One technical effect of the embodiment of the application is that:

in the application, the utilization of S polarized light is realized by using the first prism group to be matched with the LCOS chip, and the utilization of P polarized light is realized by using the second prism group and the 1/4 wave plate to be matched with the LCOS chip. The binocular display of S polarized light and P polarized light in the illumination light beam is realized through different light path systems, the volume and the cost of the optical module are greatly reduced, the power consumption of a binocular display optical machine is reduced, the subsequent miniaturized design is more convenient, and the integrated design of the rear-end AR head-mounted display device is more facilitated.

Other features of the present application and its advantages will become apparent from the following detailed description of exemplary embodiments of the application, which proceeds with reference to the accompanying drawings.

Drawings

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

FIG. 1 is a schematic diagram of an AR display system according to an embodiment of the present application;

FIG. 2 is a schematic diagram of a second embodiment of an AR display system;

FIG. 3 is a third schematic diagram of an AR display system according to an embodiment of the present application;

fig. 4 is a schematic diagram of an AR display system according to an embodiment of the present application.

Reference numerals illustrate:

10. an illumination light source; 21. a first prism; 22. a second prism; 31. a third prism; 32. a fourth prism; 40. a 1/4 wave plate; 51. a first chip; 52. a second chip; 60. an optical waveguide; 61. a first coupling-in region; 62. a first coupling-out region; 63. a second coupling-in region; 64. a second coupling-out region; 70. a corner prism; 80. and a lens module.

Detailed Description

Various exemplary embodiments of the present application will now be described in detail with reference to the accompanying drawings. It should be noted that: the relative arrangement of the components and steps, numerical expressions and numerical values set forth in these embodiments do not limit the scope of the present application unless it is specifically stated otherwise.

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

Techniques, methods, and apparatus known to one of ordinary skill in the relevant art may not be discussed in detail, but are intended to be part of the specification where appropriate.

In all examples shown and discussed herein, any specific values should be construed as merely illustrative, and not a limitation. Thus, other examples of exemplary embodiments may have different values.

It should be noted that: like reference numerals and letters denote like items in the following figures, and thus once an item is defined in one figure, no further discussion thereof is necessary in subsequent figures.

The application discloses an AR display system used for a head-mounted display device.

As shown in fig. 1 to 4, the AR display system includes an illumination light source 10, a first prism group, a second prism group, a 1/4 wave plate 40, an LCOS chip, and an optical waveguide 60;

the illumination light source 10 is used for emitting S polarized light and P polarized light;

the optical waveguide 60 is provided with a first coupling-in region 61, a second coupling-in region 63, a first coupling-out region 62 and a second coupling-out region 64;

the first prism group is used for reflecting the S polarized light to the LCOS chip, and the LCOS chip is used for modulating the received S polarized light into P polarized light, and the P polarized light enters the first coupling-in area 61 and is coupled out from the first coupling-out area 62;

the 1/4 wave plate 40 is disposed on a side of the second prism set away from the first prism set, the 1/4 wave plate 40 is configured to modulate P polarized light emitted by the illumination light source 10 into S polarized light, the second prism set is configured to reflect the S polarized light modulated by the 1/4 wave plate 40 to the LCOS chip, and the LCOS chip is configured to modulate the received S polarized light into P polarized light, and inject the P polarized light into the second coupling-in region 63 and couple the P polarized light out of the second coupling-out region 64.

As shown in fig. 1, the AR display system includes an illumination light source 10, a first prism group, a second prism group, a 1/4 wave plate 40, an LCOS chip, and an optical waveguide 60. Wherein:

the illumination light source 10 is used for emitting S-polarized light and P-polarized light.

The optical waveguide 60 is provided with a first coupling-in region 61, a second coupling-in region 63, a first coupling-out region 62 and a second coupling-out region 64. The first coupling-out region 62 is used for coupling out the light incident on the first coupling-in region 61. The second coupling-out region 64 is used for coupling out the light incident on the second coupling-in region 63. The optical waveguide 60 may be provided in one or more. Preferably, the optical waveguide 60 is provided with two, corresponding to both eyes of the user, respectively.

The first prism group and the second prism group adopt PBS prisms. The light splitting surface of the PBS prism can have different transmission and reflection functions according to different coating processes. For example, the PBS prism can transmit P-polarized light and reflect S-polarized light, or transmit S-polarized light and reflect P-polarized light.

In this embodiment, the S polarized light is S polarized light, and the P polarized light is P polarized light. The first prism group and the second prism group each use a PBS prism capable of transmitting P polarized light and reflecting S polarized light. Preferably, the light splitting surfaces of the first prism group and the second prism group are obliquely arranged along the axial direction and form 45 degrees with the axial line, so that P polarized light is transmitted and S polarized light is reflected.

The 1/4 wave plate 40 is disposed on a side of the second prism set away from the first prism set. The 1/4 wave plate 40 is used for modulating the P polarized light emitted by the illumination light source 10 into S polarized light, and reflecting the modulated S polarized light to the LCOS chip.

Correspondingly, the LCOS imaging chip can modulate P polarized light into S polarized light and emit the S polarized light, and can modulate P polarized light into P polarized light and emit the P polarized light according to the S polarized light, which can be realized through setting according to requirements.

When the AR display system provided by the application is used, S polarized light and P polarized light emitted by the illumination light source 10 are effectively utilized through different light path systems. Specifically:

the S polarized light emitted from the illumination light source 10 is first reflected to the LCOS chip by the first prism set after passing through the first prism set. The S polarized light is modulated into P polarized light by the LCOS chip and exits to the first coupling-in region 61. The P-polarized light incident on the first coupling-in region 61 is coupled out from the first coupling-out region 62 to the first target location. The first target position is, for example, the left eye of the user.

The P polarized light emitted from the illumination light source 10 first passes through the first prism set and the second prism set to be incident on the 1/4 wave plate 40, and is modulated into S polarized light by the 1/4 wave plate 40. The S polarized light modulated by the 1/4 wave plate 40 is reflected to the second prism group and is reflected to the LCOS chip by the second prism group. The S polarized light modulated by the 1/4 wave plate 40 is modulated into P polarized light by the LCOS chip, and exits to the second coupling-in region 63. The P-polarized light incident on the second coupling-in region 63 is coupled out from the second coupling-out region 64 to a second target location. The second target position is, for example, the right eye of the user.

In the conventional illumination light path, only one PBS prism is provided so that it can use only one of S-polarized light or P-polarized light, resulting in poor imaging quality.

In the application, the utilization of S polarized light is realized by using the first prism group to be matched with the LCOS chip, and the utilization of P polarized light is realized by using the second prism group and the 1/4 wave plate 40 to be matched with the LCOS chip. The binocular display of S polarized light and P polarized light in the illumination light beam is realized through different light path systems, the volume and the cost of the optical module are greatly reduced, the power consumption of a binocular display optical machine is reduced, the subsequent miniaturized design is more convenient, and the integrated design of the rear-end AR head-mounted display device is more facilitated.

In the embodiment of the present application, the first prism group includes a first prism 21 and a second prism 22, and the second prism group includes a third prism 31 and a fourth prism 32; wherein,,

the first prism 21 and the fourth prism 32 are symmetrically arranged, and the second prism 22 and the third prism 31 are symmetrically arranged.

Referring to fig. 1, the first prism group includes a first prism 21 and a second prism 22, and the first prism 21 and the second prism 22 are connected, for example, by gluing. A first light splitting surface is arranged between the first prism 21 and the second prism 22, and the first light splitting surface is obliquely arranged along the axis direction and forms 45 degrees with the axis. The first light splitting surface of the first prism group is used for reflecting the S polarized light emitted by the illumination light source 10 to the LCOS chip.

With continued reference to fig. 1, the second prism set includes a third prism 31 and a fourth prism 32. The third prism 31 and the fourth prism 32 are connected, for example, by gluing. The third prism 31 is disposed symmetrically to the second prism 22, and the fourth prism 32 is disposed symmetrically to the first prism 21. A second light splitting surface is arranged between the third prism 31 group and the fourth prism 32 group. The second light splitting surface is obliquely arranged along the axis direction and forms 45 degrees with the axis, and the first light splitting surface is perpendicular to the second light splitting surface. The second dichroic surface is used for reflecting the S polarized light modulated by the 1/4 wave plate 40 to the LCOS chip.

In the application, the first prism group and the second prism group which are symmetrical to each other are arranged to form the light path designs respectively aiming at the S polarized light and the P polarized light, thereby realizing the utilization of the S polarized light and the P polarized light at the same time, namely realizing binocular display. The volume and the cost of the optical module are greatly reduced, the power consumption of the binocular display optical machine is reduced, and the subsequent miniaturization design is more convenient.

In one embodiment of the present application, the second prism 22 and the third prism 31 are separately disposed with a gap therebetween.

In another embodiment of the present application, the second prism 22 is fixedly connected to the third prism 31.

As shown in fig. 2, the second prism 22 and the third prism 31 are symmetrically arranged, and the second prism 22 and the third prism 31 are fixedly connected. The second prism 22 and the third prism 31 are, for example, integrally formed, and of course, the second prism 22 and the third prism 31 may be glued and fixed.

In the application, the second prism 22 and the third prism 31 are fixedly connected to form a whole, so that the volumes of the first prism group and the second prism group in the AR display system are further reduced, the volume and the cost of the optical module are greatly reduced, and the whole miniaturization of the AR display system is realized.

In the embodiment of the present application, a reflecting mirror is disposed on a side of the 1/4 wave plate 40 away from the second prism group; or,

the side of the 1/4 wave plate 40 away from the second prism group is provided with a high reflection film.

In the present application, the 1/4 wave plate 40 is used to modulate the P-polarized light emitted from the illumination source 10 into S-polarized light. Specifically, after the P polarized light emitted by the illumination light source 10 passes through the 1/4 wave plate 40, the two components generate a 1/4 wavelength phase difference, after the P polarized light is reflected back, the directions and the phase differences of the two components are unchanged, the P polarized light passes through the 1/4 wave plate 40 again, the two components are overlapped with 1/4 wavelength phase difference again, and the P polarized light has a 1/2 phase difference, so that the synthesized light is linearly polarized light, and the polarization direction is perpendicular to the original direction.

In one embodiment of the present application, a mirror is disposed on the side of the 1/4 wave plate 40 remote from the second prism set. The reflection of P polarized light is realized through the reflector, so that the replacement of the reflector is convenient to realize.

In one embodiment of the present application, a highly reflective film is coated on a surface of the side of the 1/4 wave plate 40 remote from the second prism group. A highly reflective film, i.e., a highly reflective film, is an optical film that will reflect most or almost all of the incident light energy back. The reflectivity of the 1/4 wave plate 40 can be improved by plating a film with a set thickness on the 1/4 wave plate 40. And the occupied volume is smaller, which is beneficial to realizing the miniaturization of the AR display system.

In the embodiment of the present application, the LCOS chip includes a first chip 51 and a second chip 52, where the first chip 51, the first prism group and the first coupling-in area 61 are sequentially disposed along a first axis, and the second chip 52, the second prism group and the second coupling-in area 63 are sequentially disposed along a second axis;

wherein the first axis is parallel to the second axis.

Referring to fig. 1, the lcos chip includes a first chip 51 and a second chip 52. The first chip 51, the first prism group and the first coupling-in region 61 are sequentially disposed along the first axis. The second chip 52, the second prism group and the second coupling-in area 63 are sequentially disposed along the second axis. Wherein the first axis and the second axis are parallel to each other.

The S-polarized light emitted from the illumination light source 10 is first reflected by the first prism group to the first chip 51 after passing through the first prism group. The S polarized light is modulated into P polarized light by the first chip 51, and exits to the first coupling-in region 61. The P-polarized light incident on the first coupling-in region 61 is coupled out from the first coupling-out region 62 to the first target location. The first target position is, for example, the left eye of the user.

The P polarized light emitted from the illumination light source 10 first passes through the first prism set and the second prism set to be incident on the 1/4 wave plate 40, and is modulated into S polarized light by the 1/4 wave plate 40. The S-polarized light modulated by the 1/4 wave plate 40 is then reflected to the second prism group and reflected by the second prism group to the second chip 52. The S polarized light modulated by the 1/4 wave plate 40 is then modulated into P polarized light by the second chip 52, and exits to the second coupling-in region 63. The P-polarized light incident on the second coupling-in region 63 is coupled out from the second coupling-out region 64 to a second target location. The second target position is, for example, the right eye of the user.

In the application, the first chip 51 and the second chip 52 are arranged to respectively process the light rays reflected by the first prism group and the second prism group, thereby improving the processing efficiency of the light rays and further improving the overall optical effect of the AR display system.

In the embodiment of the present application, a corner prism 70 is disposed between the illumination light source 10 and the first prism group, and the corner prism 70 is used for injecting the light emitted from the illumination light source 10 into the first prism group.

Referring to fig. 3 and 4, the ar display system further includes a corner prism 70. The corner prism 70, the first prism set and the second prism set are sequentially arranged along an axis. The locations of the illumination sources 10 are arranged according to specific needs.

In use, the S-polarized light and the P-polarized light emitted from the illumination source 10 are simultaneously changed in optical path by the corner prism 70 and are incident on the first prism group.

In the embodiment of the application, the illumination light source 10 is longitudinally folded by arranging the corner prism 70, so that the overall compact design of the AR display system is realized, and the overall miniaturization of the AR display system is further improved.

In the embodiment of the present application, the projection lens module 80 is further included, and the projection lens module 80 is disposed between the optical waveguide 60 and the LCOS chip.

The AR display system further includes a projection lens module 80. The projection lens module 80 includes, for example, at least one of a projection lens and a lens. The projection lens module 80 is disposed between the optical waveguide 60 and the LCOS chip. Specifically:

in one embodiment of the present application, the projection lens module 80 is disposed between the first prism set and the LCOS chip, and between the second prism set and the LCOS chip.

In one embodiment of the present application, the projection lens module 80 is disposed between the first prism assembly and the first coupling-in region 61 of the optical waveguide 60, and between the second prism assembly and the second coupling-in region 63 of the optical waveguide 60.

In one embodiment of the present application, as shown in fig. 1-4, the projection lens modules 80 are disposed on both sides of the first prism set and on both sides of the second prism set.

It should be noted that, the projection lens module 80 is designed according to the actual optical requirement. The specific structure of the projection lens module 80 is not particularly limited in the present application.

In the embodiment of the present application, a polarizing device is disposed on a side of the optical waveguide 60 near the LCOS chip, and the polarizing device is used for filtering stray light.

The polarizing device comprises a polaroid, a wave plate, a vortex wave plate, a polarizing prism, a polarizing beam splitter, a compensator, a depolarizer, an optical rotator, a polarization measuring instrument and the like.

In one embodiment of the present application, the polarizing device is disposed on a side of the first prism set and the second prism set away from the LCOS chip. Namely, the polarizing device is arranged on the light emergent surfaces of the first prism group and the second prism group.

In another embodiment of the present application, the polarizing device is disposed on a side of the first coupling-in region 61 near the first prism set, and on a side of the second coupling-in region 63 near the second prism set. That is, the polarizer is disposed on the light incident surfaces of the first coupling-in region 61 and the second coupling-in region 63.

In the embodiment of the present application, by arranging the polarizing device on the side of the optical waveguide 60 close to the LCOS chip, stray light in the light incident into the first coupling-in region 61 and the second coupling-in region 63 is filtered, so as to improve the imaging effect of the AR display system.

In the embodiment of the present application, a phase retarder is disposed on a side of the LCOS chip close to the optical waveguide 60.

In the present application, the phase retarder is disposed on a surface of the LCOS chip, for example, near the optical waveguide 60. The number of the phase delay plates is two, and the two phase delay plates are respectively arranged in one-to-one correspondence with the first coupling-in area 61 and the second coupling-in area 63.

The phase retarder may be replaced with a 1/4 wave plate.

According to the application, the phase delay piece is arranged on the surface of the LCOS chip, so that the phase delay of light rays incident into the LCOS chip can be corrected, and the imaging effect of the AR display system is improved.

The application also provides a head-mounted display device comprising the AR display system.

While certain specific embodiments of the application have been described in detail by way of example, it will be appreciated by those skilled in the art that the above examples are for illustration only and are not intended to limit the scope of the application. It will be appreciated by those skilled in the art that modifications may be made to the above embodiments without departing from the scope and spirit of the application. The scope of the application is defined by the appended claims.

Claims

1. An AR display system is characterized by comprising an illumination light source (10), a first prism group, a second prism group, a 1/4 wave plate (40), an LCOS chip and an optical waveguide (60);

the illumination light source (10) is used for emitting S polarized light and P polarized light;

the optical waveguide (60) is provided with a first coupling-in region (61), a second coupling-in region (63), a first coupling-out region (62) and a second coupling-out region (64);

the first prism group is used for reflecting the S polarized light to the LCOS chip, and the LCOS chip is used for modulating the received S polarized light into P polarized light, and the P polarized light enters the first coupling-in area (61) and is coupled out from the first coupling-out area (62);

the 1/4 wave plate (40) is arranged on one side, far away from the first prism group, of the second prism group, the 1/4 wave plate (40) is used for modulating P polarized light emitted by the illumination light source (10) into S polarized light, the second prism group is used for reflecting the S polarized light modulated by the 1/4 wave plate (40) to the LCOS chip, and the LCOS chip is used for modulating the received S polarized light into P polarized light, injecting the P polarized light into the second coupling-in region (63) and coupling out the P polarized light from the second coupling-out region (64).

2. The AR display system according to claim 1, wherein the first prism set comprises a first prism (21) and a second prism (22), the second prism set comprising a third prism (31) and a fourth prism (32); wherein,,

the first prism (21) and the fourth prism (32) are symmetrically arranged, and the second prism (22) and the third prism (31) are symmetrically arranged.

3. The AR display system according to claim 2, characterized in that the second prism (22) is fixedly connected with the third prism (31).

4. The AR display system according to claim 1, characterized in that a side of the 1/4 wave plate (40) remote from the second set of prisms (22) is provided with a mirror; or,

and a high-reflection film is arranged on one side of the 1/4 wave plate (40) far away from the second prism group.

5. The AR display system according to claim 1, wherein the LCOS chip comprises a first chip (51) and a second chip (52), the first chip (51), the first prism group and the first coupling-in region (61) being arranged in sequence along a first axis, the second chip (52), the second prism group and the second coupling-in region (63) being arranged in sequence along a second axis;

wherein the first axis is parallel to the second axis.

6. The AR display system according to claim 1, characterized in that a corner prism (70) is arranged between the illumination source (10) and the first prism group, the corner prism (70) being used for injecting light rays exiting from the illumination source (10) into the first prism group.

7. The AR display system according to claim 1, further comprising a projection lens module (80), the projection lens module (80) being disposed between the optical waveguide (60) and the LCOS chip.

8. The AR display system according to claim 1, characterized in that a polarizing device is provided on a side of the optical waveguide (60) close to the LCOS chip, said polarizing device being used for filtering parasitic light.

9. The AR display system according to claim 1, characterized in that a phase retarder is provided on a side of the LCOS chip close to the optical waveguide (60).

10. A head-mounted display device comprising the AR display system of any one of claims 1-9.