CN213780549U

CN213780549U - Imaging module and augmented reality equipment

Info

Publication number: CN213780549U
Application number: CN202120030072.6U
Authority: CN
Inventors: 李琨; 饶轶; 刘德安
Original assignee: Goertek Inc
Current assignee: Goertek Inc
Priority date: 2021-01-06
Filing date: 2021-01-06
Publication date: 2021-07-23
Anticipated expiration: 2031-01-06

Abstract

The utility model discloses an imaging module and augmented reality equipment, wherein, imaging module includes: an optical machine; the optical waveguide comprises a light-transmitting substrate, an incident grating and an emergent grating, wherein the incident grating and the emergent grating are arranged on the light-transmitting substrate and correspond to the optical machine; and the diffraction imaging element is positioned on the light-emitting path of the optical waveguide and is arranged opposite to the emergent grating. The technical scheme of the utility model can reduce the product to the physical restriction that conditions such as printing opacity basement material high refractive index brought, increase the product angle of vision, promote the product light efficiency, reinforcing product luminance homogeneity.

Description

Imaging module and augmented reality equipment

Technical Field

The utility model relates to an optical equipment technical field, in particular to formation of image module and augmented reality equipment.

Background

Augmented Reality (AR) technology is a technology for calculating the position and angle of a camera image in real time and adding corresponding images, videos and 3D models, and aims to superimpose a virtual world on a real world on a screen and interact with the virtual world.

Some augmented realityThe apparatus employs an imaging module comprising a light engine 20 'and a light guide 10'. Referring to fig. 1, a conventional optical waveguide 10' includes a light-transmitting substrate 11', and an incident grating 12' and an exit grating 13' provided on the light-transmitting substrate 11 '; the conventional optical engine 20 'includes a micro display screen 21' and an imaging prism 22 'or a prism set disposed in front of the micro display screen 21', and each pixel on the micro display screen 21 'is converged at an optical engine exit pupil 23' or a waveguide entrance pupil via the imaging prism 22 'or the prism set, and is coupled into the light-transmissive substrate 11' through the incident grating 12', and finally exits from the exit grating 13' to be input to the human eye. The included angle formed by the light beams formed by the edge-most pixel points is the field of view (FOV); it will be appreciated that the light rays incident on the diffractive light waveguide 10 'through the optical machine exit pupil 23' or waveguide entrance pupil are at a plurality of angles, the range of incidence angles θ_iI.e. the FOV.

Because the diffraction grating has sensitivity to the incident angle, that is, the light incident at different angles is diffracted by the incident grating 12' and then the emergent angles are different, a diffraction angle range delta theta is formed_d. In the propagation principle of the optical waveguide 10', the material of the transparent substrate 11' needs to have a refractive index large enough to support light rays with a large diffraction angle range to satisfy the total reflection condition, i.e. the light rays can propagate in the optical waveguide 10 '. Therefore, the development of the material of the light-transmitting substrate 11 'is one of the limitations of the FOV of the optical waveguide 10'.

In addition, due to the sensitivity of the diffraction grating to the incident angle, the diffraction efficiency of light at different incident angles is also different, which causes a phenomenon that the display brightness is not uniformly distributed within the FOV. In order to improve the brightness uniformity, the incident grating 12' is usually optimized to select the design parameters with better angle uniformity, but the overall coupling efficiency is sacrificed, which affects the luminous efficiency of the product.

The above is only for the purpose of assisting understanding of the technical solutions of the present invention, and does not represent an admission that the above is the prior art.

SUMMERY OF THE UTILITY MODEL

The utility model aims at providing an imaging module, aim at reducing its physical restriction that brings to conditions such as printing opacity basement material high refractive index, increase its angle of vision, promote its light efficiency, strengthen its luminance homogeneity.

In order to achieve the above object, the utility model provides an imaging module includes:

the method comprises the following steps:

an optical machine;

the optical waveguide comprises a light-transmitting substrate, an incident grating and an emergent grating, wherein the incident grating and the emergent grating are arranged on the light-transmitting substrate and correspond to the optical machine; and the number of the first and second groups,

and the diffraction imaging element is positioned on the light outgoing path of the optical waveguide and is arranged opposite to the emergent grating.

Optionally, the diffractive imaging element is configured as an imaging grating.

Optionally, the imaging grating is configured as a surface relief grating or a holographic grating.

Optionally, the material of the diffractive imaging element is an organic resin material or a dielectric material or a polymer material or a liquid crystal material.

Optionally, the transparent substrate is made of glass.

Optionally, the exit grating is disposed on a side of the light-transmissive substrate facing away from the diffractive imaging element.

Optionally, the optical engine includes a micro display screen and a collimating element located at a front side of the micro display screen, and light emitted by the micro display screen is transmitted to the optical waveguide in parallel after passing through the collimating element.

Optionally, the optical engine adopts a parallel light source, so that light emitted by the optical engine is transmitted to the optical waveguide in parallel.

Optionally, the light transmitted to the optical waveguide is perpendicularly incident to the optical waveguide.

The utility model discloses still provide an augmented reality equipment, including aforementioned imaging module.

The technical proposal of the utility model is that a diffraction imaging element opposite to the emergent grating is arranged on the emergent light path of the optical waveguide, and the front side of the micro display screen of the optical machine does not need to be provided with imaging elements such as an imaging prism or a prism group and the like, namely, the imaging elements in the imaging module are moved from the incident end to the emergent end of the optical waveguide, so that, when the optical machine outputs parallel light to the optical waveguide, the angles of the light rays incident on the incident grating are the same, the diffraction angle is also the same, there is no angular difference due to different incident angles, and therefore, as long as the diffraction angle satisfies the total reflection condition of the light-transmitting substrate, therefore, the physical limitation of the imaging module on the conditions of high refractive index and the like of the light-transmitting substrate material can be reduced, the field angle of the imaging module is increased, the design difficulty of the incident grating can be reduced, and the design pressure of the optical waveguide is reduced; in addition, because the incident angles are the same, the coupling-in efficiency of each pixel is the same, and the coupling-out efficiency is the same after passing through the emergent grating, so that the efficiency of the whole field angle is uniform, and the solution with the highest efficiency at the angle can be selected, thereby being beneficial to improving the light efficiency of the imaging module and improving the uniformity of the brightness of the imaging module.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings needed to be used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the structures shown in the drawings without creative efforts.

FIG. 1 is a schematic structural diagram of an imaging module in the background art;

fig. 2 is a schematic structural diagram of an embodiment of the imaging module of the present invention.

Description of the reference numerals in the background art:

reference numerals	Name (R)	Reference numerals	Name (R)
				10’	Optical waveguide	11’	Light-transmitting substrate
12’	Incident grating	13’	Emergent grating
				20’	Optical machine	21’	Micro display screen
22’	Imaging prism	23’	Exit pupil of optical machine

The reference numerals in the detailed description illustrate:

the objects, features and advantages of the present invention will be further described with reference to the accompanying drawings.

Detailed Description

The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative efforts belong to the protection scope of the present invention.

It should be noted that if directional indications (such as up, down, left, right, front, and back … …) are involved in the embodiment of the present invention, the directional indications are only used to explain the relative position relationship between the components, the motion situation, etc. in a specific posture, and if the specific posture is changed, the directional indications are changed accordingly.

In addition, if there is a description relating to "first", "second", etc. in the embodiments of the present invention, the description of "first", "second", etc. is for descriptive purposes only and is not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In addition, if the meaning of "and/or" and/or "appears throughout, the meaning includes three parallel schemes, for example," A and/or B "includes scheme A, or scheme B, or a scheme satisfying both schemes A and B. In addition, the technical solutions in the embodiments may be combined with each other, but it must be based on the realization of those skilled in the art, and when the technical solutions are contradictory or cannot be realized, the combination of the technical solutions should not be considered to exist, and is not within the protection scope of the present invention.

The utility model provides an imaging module.

Referring to fig. 2, in an embodiment of the present invention, the imaging module includes:

a light engine 20;

the optical waveguide 10 comprises a light-transmitting substrate 11, and an incident grating 12 and an exit grating 13 which are arranged on the light-transmitting substrate 11, wherein the incident grating 12 is arranged corresponding to the optical machine 20; and the number of the first and second groups,

and a diffraction imaging element 30 located on the light exit path of the optical waveguide 10 and disposed opposite to the exit grating 13.

In this embodiment, the optical waveguide 10 is specifically configured as a diffraction optical waveguide 10, and the incident grating 12 and the exit grating 13 are both configured as diffraction gratings. The incident grating 12 is disposed corresponding to the optical machine 20, which means that the optical machine 20 is disposed toward the incident grating 12. It should be noted that, as shown in fig. 2, the incident grating 12 is disposed on a side of the light-transmitting substrate 11 facing away from the optical engine 20; however, the design is not limited thereto, and in other embodiments, the incident grating 12 may also be disposed on a side of the transparent substrate 11 facing the optical engine 20.

In this embodiment, after the light is emitted under the diffraction action of the exit grating 13, the diffraction imaging element 30 completes the task of light convergence and imaging, so that human eyes can see a complete image. Generally, the diffractive imaging element 30 will be optimized according to design requirements, so that the light after imaging is still uniformly distributed throughout the eye box, and no bright spots or dark stripes are generated.

The technical scheme of the utility model is through set up on the light-emitting path of optical waveguide 10 with diffraction imaging element 30 that exit grating 13 is relative, and the little display screen 21 front side of ray apparatus 20 need not to set up imaging element such as formation of image prism or prism group, promptly, will imaging element in the imaging module moves to the exit end from the incident end of optical waveguide 10, so, through ray apparatus 20 to when optical waveguide 10 exports the parallel light, the light angle of incidenting on incident grating 12 is the same, and then the diffraction angle is also the same, does not have the angle difference that arouses because different incident angles, consequently, as long as the diffraction angle satisfies the total reflection condition of printing opacity basement 11, thereby can reduce the physics restriction that this imaging module brought the conditions such as high refractive index of printing opacity basement 11 material, increase its angle of vision, the design degree of difficulty of incident grating 12 also can reduce, thereby relieving the design pressure of the optical waveguide 10; in addition, since the incident angles are the same, the coupling-in efficiency of each pixel is the same, and the coupling-out efficiency is the same after passing through the exit grating 13, so that the efficiency of the whole field angle is uniform, and the solution with the highest efficiency at the angle can be selected, thereby being beneficial to improving the light efficiency of the imaging module and improving the uniformity of the brightness of the imaging module.

Further, the diffractive imaging element 30 is configured as an imaging grating, so that after the emergent light is diffracted by the imaging grating, the convergence and imaging of the light are completed, and thus, a complete image can be seen by human eyes. In this embodiment, the imaging grating may be configured as, but not limited to, a surface relief grating or a holographic grating. In addition, the material of the diffractive imaging element 30 may be, but is not limited to, an organic resin material, a dielectric material, a polymer material, a liquid crystal material, or the like.

Further, the transparent substrate 11 is made of glass, and the refractive index of the glass is high, so that total reflection of internal light is facilitated, and incident light is conveyed to the exit grating 13. However, the design is not limited thereto, and in other embodiments, the material of the transparent substrate 11 may also be other transparent materials with higher refractive index and transparent in the visible light band.

Further, the exit grating 13 is disposed on a side of the light-transmissive substrate 11 facing away from the diffractive imaging element 30. That is, in the embodiment, the exit grating 13 and the diffractive imaging element 30 are respectively disposed on two opposite sides of the light-transmitting substrate 11, so that the diffractive imaging element 30 can be disposed close to the light-transmitting substrate 11, and the structure of the imaging module is more compact. However, the design is not limited thereto, and in other embodiments, the exit grating 13 may also be disposed on a side of the light-transmitting substrate 11 facing the diffractive imaging element 30, that is, the exit grating 13 and the diffractive imaging element 30 may be located on a same side of the light-transmitting substrate 11.

In this embodiment, optionally, the diffractive imaging element 30 is separately disposed on the light-transmitting substrate 11 (see fig. 2). However, the design is not limited thereto, and in other embodiments, the diffractive imaging element 30 may also be attached to the transparent substrate 11, or directly formed on a side of the transparent substrate 11 away from the exit grating 13, so as to improve the modularization degree of the product, reduce the number of components to be assembled, and improve the assembly efficiency of the product.

Further, the optical machine 20 includes a micro display screen 21 and a collimating element 22 located at the front side of the micro display screen 21, and light emitted by the micro display screen 21 passes through the collimating element 22 and then is transmitted to the optical waveguide 10 in parallel; it can be understood that the collimating element 22 is configured to collimate each pixel of the micro display panel 21 into a plurality of parallel light beams, so that the light beams incident on the light guide 10 corresponding to each pixel are parallel light beams, that is, the angles of the light beams incident on the incident grating 12 are the same, and the diffraction angles of the light beams are the same, and there is no angle difference caused by different incident angles. However, the design is not limited to this, in other embodiments, the optical machine 20 may further adopt a parallel light source, so that the light emitted by the optical machine 20 is transmitted to the optical waveguide 10 in parallel, and thus, the light rays corresponding to each pixel incident on the optical waveguide 10 are also made to be parallel light, and after the light rays are diffracted by the incident grating 12, the diffraction angles of the light rays are the same, and there is no angle difference caused by different incident angles. Additionally, the utility model discloses in, optionally, transmit extremely the light vertical incidence of optical waveguide 10, that is, the incident angle of all light is zero, so, can make when incident angle is the same, make all light can both get into optical waveguide 10 reduces light is getting into light loss when optical waveguide 10 to be favorable to improving the light efficiency of formation of image module.

The utility model discloses still provide an augmented reality equipment, this imaging module include the imaging module, and the concrete structure of this imaging module refers to above-mentioned embodiment, because this augmented reality equipment has adopted the whole technical scheme of above-mentioned all embodiments, consequently has all beneficial effects that the technical scheme of above-mentioned embodiment brought at least, and the repeated description is no longer given here.

The above only is the preferred embodiment of the present invention, not limiting the scope of the present invention, all the equivalent structure changes made by the contents of the specification and the drawings under the inventive concept of the present invention, or the direct/indirect application in other related technical fields are included in the patent protection scope of the present invention.

Claims

1. An imaging module, comprising:

an optical machine;

2. The imaging module of claim 1, wherein the diffractive imaging element is configured as an imaging grating.

3. The imaging module of claim 2 wherein the imaging grating is configured as a surface relief grating or a holographic grating.

4. The imaging module of claim 1, wherein the material of the diffractive imaging element is an organic resin material or a dielectric material or a polymer material or a liquid crystal material.

5. The imaging module of claim 1, wherein the transparent substrate is made of glass.

6. The imaging module of claim 1 wherein the exit grating is disposed on a side of the light transmissive substrate facing away from the diffractive imaging element.

7. The imaging module of claim 1, wherein the optical engine comprises a micro display screen and a collimating element located at a front side of the micro display screen, and light emitted by the micro display screen is transmitted in parallel to the optical waveguide after passing through the collimating element.

8. The imaging module of claim 1, wherein the optical engine employs a parallel light source to transmit light emitted by the optical engine to the optical waveguide in parallel.

9. The imaging module of claim 7 or 8, wherein light transmitted to the optical waveguide is incident normally to the optical waveguide.

10. Augmented reality device, comprising an imaging module according to any one of claims 1 to 9.