阅读说明：本技术 一种光波导、近眼显示系统及光波导耦出区域的设计方法 (Optical waveguide, near-to-eye display system and design method of optical waveguide coupling-out area ) 是由 郭晓明 宋强 段辉高 胡跃强 马国斌 于 2020-06-24 设计创作，主要内容包括：本发明实施例涉及光学设计技术领域,公开了一种光波导、近眼显示系统及光波导耦出区域的设计方法,该光波导包括：耦入区域和耦出区域,所述耦入区域用于耦入带有图像信息的光束,所述耦出区域用于耦出所述带有图像信息的光束,其中,所述耦出区域包括：多个像素化排列的分区,所述分区包括设有光栅结构的分区和未设有光栅结构的分区,所述未设有光栅结构的分区用于全反射传播所述光束,所述设有光栅结构的分区用于耦出部分光束,以及扩展传播部分光束,所述未设有光栅结构的分区的数量沿远离所述耦入区域的方向逐渐减少,本发明实施例通过光波导耦出区域的设计方法设计出的如上述光波导能够输出均匀性较佳的光束,且加工容易。(The embodiment of the invention relates to the technical field of optical design, and discloses an optical waveguide, a near-eye display system and a design method of an optical waveguide coupling-out area, wherein the optical waveguide comprises the following components: an in-coupling region for in-coupling the light beam with image information and an out-coupling region for out-coupling the light beam with image information, wherein the out-coupling region comprises: the optical waveguide comprises a plurality of partitions which are arranged in a pixelization mode, wherein each partition comprises a partition with a grating structure and a partition without the grating structure, the partition without the grating structure is used for transmitting the light beams in a total reflection mode, the partition with the grating structure is used for coupling out part of the light beams and expanding and transmitting part of the light beams, and the number of the partitions without the grating structures is gradually reduced along the direction far away from the coupling-in area.)

1. An optical waveguide, comprising: an in-coupling region for in-coupling in the light beam with image information and an out-coupling region for out-coupling the light beam with image information, wherein,

the coupling-out region includes: the device comprises a plurality of subareas which are arranged in a pixelization mode, wherein each subarea comprises a subarea provided with a grating structure and a subarea not provided with the grating structure, the subarea not provided with the grating structure is used for totally reflecting and transmitting the light beam, the subarea provided with the grating structure is used for coupling out part of the light beam and expanding and transmitting part of the light beam, and the number of the subareas not provided with the grating structure is gradually reduced along the direction far away from the coupling-in area.

2. The optical waveguide of claim 1,

the optical waveguide further comprises a waveguide substrate, the coupling-in region and the coupling-out region being arranged on the waveguide substrate.

3. The optical waveguide of claim 2,

the shape of the partitions is a parallelogram and/or the shape of the partitions corresponds to the periodic shape of the grating of the coupling-out region.

4. The optical waveguide of claim 3,

and the parameters of the grating structures in the partitions provided with the grating structures are consistent.

5. The optical waveguide of claim 4,

in the coupling-out region, the size of each of the subareas is uniform, the size of the subarea is smaller than an eye pupil diameter, and the eye pupil diameter is 4 mm.

6. The optical waveguide of any of claims 1-5,

the structure of the coupling-in area is one of a reflector, a prism, a free-form surface structure, a grating structure, a super-surface structure, a volume holographic structure or a resonance grating structure.

7. The optical waveguide of any of claims 1-5,

the structure of the coupling-out area is one of a two-dimensional grating structure, a super-surface structure, a volume holographic structure or a resonance grating structure.

8. A near-eye display system, comprising: a micro-projector, and an optical waveguide according to any of the preceding claims 1-7.

9. A method for designing an outcoupling region of an optical waveguide, the method being applied to an outcoupling region of an optical waveguide, the optical waveguide further comprising an outcoupling region for incoupling a light beam with image information, the outcoupling region being for outcoupling the light beam with image information, the method comprising:

dividing the out-coupling region into a plurality of pixelated partitions;

arranging a grating structure on part of the subareas so that the coupling-out efficiency of the coupling-out area is relatively uniform; wherein the content of the first and second substances,

the subareas without the grating structures are used for totally reflecting and propagating the light beams, the subareas with the grating structures are used for coupling out partial light beams and expanding and propagating partial light beams, and the number of the subareas without the grating structures is gradually reduced along the direction far away from the coupling-in area.

10. The design method according to claim 9,

the shape of the partitions is a parallelogram and/or the shape of the partitions corresponds to the periodic shape of the grating of the coupling-out region.

11. The design method according to claim 10,

and the parameters of the grating structures in the partitions provided with the grating structures are consistent.

12. The design method according to claim 11,

in the coupling-out region, the size of each of the subareas is uniform, the size of the subarea is smaller than an eye pupil diameter, and the eye pupil diameter is 4 mm.

Technical Field

The embodiment of the invention relates to the technical field of optical design, in particular to an optical waveguide, a near-eye display system and a design method of an optical waveguide coupling-out area.

Background

The augmented reality technology, namely the AR technology, fuses virtual information and the real world mutually, belongs to the detonation point of the next information technology, and the augmented reality glasses are predicted to replace a mobile phone to become a next generation of cooperative computing platform according to authority. Augmented reality technologies represented by augmented reality glasses are beginning to rise in various industries at present, and particularly in the fields of security and industry, the augmented reality technologies embody the inexplicable advantages and the information interaction mode is greatly improved. At present, the mature augmented reality technology mainly comprises a prism scheme, a birdbath scheme, a free-form surface scheme and a waveguide scheme, the first three schemes have large volumes, the application of the three schemes in the aspect of intelligent wearing, namely the aspect of augmented reality glasses is limited, and the waveguide is the best augmented reality glasses scheme at present. The waveguide schemes are further classified into a geometric waveguide scheme, an embossed grating waveguide scheme, and a volume hologram waveguide scheme. The geometric waveguide scheme is to use the coated semi-transparent and semi-reflective mirror of the array to achieve the display of virtual information, but the view field and the eye movement range of the scheme are limited, and the array lens can bring the stripe effect to the picture, so the geometric waveguide scheme can not present the best display effect to human eyes. Volume holographic waveguide solutions are currently limited to large scale mass production. The embossed grating waveguide scheme is the most studied technical scheme at present due to the convenience of nano-imprinting, and has the advantages of large field of view and large eye movement range. The current scheme paths of the embossed grating waveguide mainly include a waveguide scheme based on a one-dimensional grating and a waveguide scheme based on a two-dimensional grating. The two-dimensional grating waveguide is divided into an in-coupling region and an out-coupling region, the out-coupling region has both expansion and out-coupling functions, and the uniformity of the field of view and the uniformity of the exit pupil are a great challenge of the two-dimensional grating waveguide.

In implementing the embodiments of the present invention, the inventors found that at least the following problems exist in the above related art: at present, in order to improve the uniformity of light output from the coupling-out region of the optical waveguide, the conventional method is to partition the coupling-out region, where grating parameters (such as height, duty ratio, diameter, and the like) of different partitions are different and grating periods are the same, so that the coupling-out efficiency of different partitions can be adjusted, thereby achieving the uniformity of the whole coupling-out region. However, the conventional scheme has the disadvantage of different grating parameters in different partitions, which increases the processing difficulty and increases the processing cost.

Disclosure of Invention

In view of the above-mentioned drawbacks of the prior art, an object of the embodiments of the present invention is to provide an optical waveguide, a near-eye display system and a method for designing a coupling-out region of an optical waveguide, which have good uniformity and are easy to process.

The purpose of the embodiment of the invention is realized by the following technical scheme:

in order to solve the above technical problem, in a first aspect, an embodiment of the present invention provides an optical waveguide, including: an in-coupling region for in-coupling in the light beam with image information and an out-coupling region for out-coupling the light beam with image information, wherein,

the coupling-out region includes: the device comprises a plurality of subareas which are arranged in a pixelization mode, wherein each subarea comprises a subarea provided with a grating structure and a subarea not provided with the grating structure, the subarea not provided with the grating structure is used for totally reflecting and transmitting the light beam, the subarea provided with the grating structure is used for coupling out part of the light beam and expanding and transmitting part of the light beam, and the number of the subareas not provided with the grating structure is gradually reduced along the direction far away from the coupling-in area.

In some embodiments, the optical waveguide further comprises a waveguide substrate, the coupling-in region and the coupling-out region being disposed on the waveguide substrate.

In some embodiments, the shape of the partitions is a parallelogram and/or the shape of the partitions conforms to the periodic shape of the grating of the coupling-out region.

In some embodiments, the parameters of the grating structures in each of the regions provided with grating structures are consistent.

In some embodiments, in the coupling-out region, each of the segments is uniform in size, the size of the segment is smaller than an eye pupil diameter, and the eye pupil diameter is 4 mm.

In some embodiments, the structure of the coupling-in region is one of a mirror, a prism, a free-form surface structure, a grating structure, a super-surface structure, a volume holographic structure, or a resonant grating structure.

In some embodiments, the structure of the outcoupling region is one of a two-dimensional grating structure, a super-surface structure, a volume holographic structure, or a resonant grating structure.

In order to solve the above technical problem, in a second aspect, an embodiment of the present invention provides a near-eye display system, including: a micro-projector light engine, and an optical waveguide as described above in relation to the first aspect.

In order to solve the above technical problem, in a third aspect, an embodiment of the present invention provides a method for designing a coupling-out area of an optical waveguide, the method being applied to the coupling-out area of the optical waveguide, the optical waveguide further includes a coupling-in area for coupling in a light beam with image information, and the coupling-out area is used for coupling out the light beam with image information, and the method includes:

dividing the out-coupling region into a plurality of pixelated partitions;

arranging a grating structure on part of the subareas so that the coupling-out efficiency of the coupling-out area is relatively uniform; wherein the content of the first and second substances,

the subareas without the grating structures are used for totally reflecting and propagating the light beams, the subareas with the grating structures are used for coupling out partial light beams and expanding and propagating partial light beams, and the number of the subareas without the grating structures is gradually reduced along the direction far away from the coupling-in area.

In some embodiments, the shape of the partitions is a parallelogram and/or the shape of the partitions conforms to the periodic shape of the grating of the coupling-out region.

In some embodiments, the parameters of the grating structures in each of the regions provided with grating structures are consistent.

In some embodiments, in the coupling-out region, each of the segments is uniform in size, the size of the segment is smaller than an eye pupil diameter, and the eye pupil diameter is 4 mm.

Compared with the prior art, the invention has the beneficial effects that: in contrast to the prior art, embodiments of the present invention provide an optical waveguide, a near-eye display system, and a method for designing a coupling-out region of an optical waveguide, where the optical waveguide includes: an in-coupling region for in-coupling the light beam with image information and an out-coupling region for out-coupling the light beam with image information, wherein the out-coupling region comprises: the optical waveguide comprises a plurality of partitions which are arranged in a pixelization mode, wherein each partition comprises a partition with a grating structure and a partition without the grating structure, the partition without the grating structure is used for transmitting the light beams in a total reflection mode, the partition with the grating structure is used for coupling out part of the light beams and expanding and transmitting part of the light beams, and the number of the partitions without the grating structures is gradually reduced along the direction far away from the coupling-in area.

Drawings

One or more embodiments are illustrated by the accompanying figures in the drawings that correspond thereto and are not to be construed as limiting the embodiments, wherein elements/modules and steps having the same reference numerals are represented by like elements/modules and steps, unless otherwise specified, and the drawings are not to scale.

Fig. 1 is a schematic structural diagram of an optical waveguide according to an embodiment of the present invention;

fig. 2 is a schematic structural diagram of another optical waveguide provided in the first embodiment of the present invention;

fig. 3 is a schematic structural diagram of a near-eye display system according to a second embodiment of the present invention;

fig. 4 is a flowchart illustrating a method for designing an optical waveguide coupling-out region according to a third embodiment of the present invention.

Detailed Description

The present invention will be described in detail with reference to specific examples. The following examples will assist those skilled in the art in further understanding the invention, but are not intended to limit the invention in any way. It should be noted that variations and modifications can be made by persons skilled in the art without departing from the spirit of the invention. All falling within the scope of the present invention.

In order to make the objects, technical solutions and advantages of the present application more apparent, the present application is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present application and are not intended to limit the present application.

It will be noted that when an element is referred to as being "secured to" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may be present.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used in the description of the invention herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention.

In addition, the technical features involved in the embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.

In the optical waveguide, light is coupled into a waveguide substrate through a coupling-in area grating, so that the light meets the total reflection condition and is transmitted in the substrate in a total reflection way, in a coupling-out area, part of the light is transmitted in an expanding way, and part of the light is coupled out to human eyes, thereby achieving the purpose of near-to-eye display. If the grating structure is uniform throughout the outcoupling region, the light will only propagate less and less weakly in the outcoupling region. Therefore, in order to improve the uniformity of the whole coupling-out area, the conventional method is to partition the coupling-out area, the grating parameters (such as height, duty ratio, diameter, etc.) of different partitions are different, and the grating period is the same, so that the coupling-out efficiency of different partitions can be adjusted, and the uniformity of the whole coupling-out area is achieved. The conventional scheme has the defects that different regions have different grating parameters, so that the processing difficulty is increased, and the processing cost is increased.

In order to solve the above-mentioned problems of large uniformity of light output, high processing difficulty and high cost, an embodiment of the present invention provides an optical waveguide, a near-eye display system, and a method for designing a coupling-out region of an optical waveguide, where a grating structure of the coupling-out region in the optical waveguide is designed by the method for designing the coupling-out region of the optical waveguide, so that the coupling-out efficiency of the coupling-out region is uniform, and the optical waveguide designed by the method includes: an in-coupling region for in-coupling the light beam with image information and an out-coupling region for out-coupling the light beam with image information, wherein the out-coupling region comprises: the optical waveguide comprises a plurality of subareas which are arranged in a pixelization mode, wherein each subarea comprises a subarea with a grating structure and a subarea without the grating structure, the subareas without the grating structures are used for totally reflecting and transmitting the light beams, the subareas with the grating structures are used for coupling out part of the light beams and expanding and transmitting part of the light beams, and the number of the subareas without the grating structures is gradually reduced along the direction far away from the coupling-in area.

Specifically, the embodiments of the present invention will be further explained below with reference to the drawings.