CN219758541U - Optical waveguide device for near-eye display and near-eye display device - Google Patents

Abstract

The utility model discloses an optical waveguide device for near-eye display and a near-eye display device, wherein the optical waveguide device comprises: the optical waveguide is provided with a light coupling inlet, and a coupling-in reflecting surface is arranged in the optical waveguide corresponding to the light coupling inlet; a sealing cavity is arranged at the light coupling inlet, the sealing cavity is filled with liquid high-refractive-index medium, and the liquid high-refractive-index medium is in direct contact with the light coupling inlet; the sealing cavity is provided with a coupling lens group, and the coupling lens group couples light rays into the sealing cavity; when the refractive index of the liquid high refractive index medium is n and the maximum incident angle of the light incident into the light coupling port is θ, the numerical aperture NA of the light coupling port is expressed as: na=n.sinθ.

Description

Optical waveguide device for near-eye display and near-eye display device

Technical Field

The utility model relates to the technical field of optical waveguides, in particular to an optical waveguide device for near-to-eye display.

Background

Augmented reality (Augmented Reality, AR) is a technique that smartly fuses virtual information with the real world, for example, superimposing virtual information on a real environment image. The method is defined as an interaction platform of next generation people and data after computers and mobile phones, so that communication between people and people, between people and machines and between people and data becomes more natural and efficient, and the method has important application prospects in the fields of intelligent manufacturing, aerospace, medical health, education and teaching, financial services, public safety, cultural entertainment and the like.

The AR equipment at the present stage mainly comprises AR glasses. In the prior art, the AR glasses are additionally provided with an optical module on the structure of the glasses, and the optical module outputs images to the glasses lenses for display. At present, the optical module is mainly based on various types of optical waveguides. For example, the lens is made as an optical waveguide, and information to be displayed is coupled into the optical waveguide at the edge side of the lens and displayed on the lens. However, the problem in the prior art is that the optical coupling aperture of the optical waveguide of the current AR glasses cannot be very large, and according to abbe imaging theorem, the optical coupling aperture of the optical waveguide is equivalent to a diaphragm, and when the numerical aperture of the diaphragm is smaller, the high-order diffracted light wave can be blocked from passing, that is, the diaphragm at the moment is equivalent to a low-pass filter. When too many higher-order diffracted light waves are blocked, the information to be displayed cannot be clearly imaged.

It follows that there is a need in the art for a device that increases the numerical aperture of the optical waveguide coupling, thereby allowing a clearer image display for a near-eye display device.

Disclosure of Invention

The technical purpose to be achieved by the utility model is to improve the numerical aperture of the optical waveguide light coupling port, so that higher-order diffraction light can pass through the coupling port more, thereby improving the resolution of image display.

Based on the technical object, the present utility model provides an optical waveguide device for near-eye display, the optical waveguide device comprising: the optical waveguide is provided with a light coupling inlet, and a coupling-in reflecting surface is arranged in the optical waveguide corresponding to the light coupling inlet; a sealing cavity is arranged at the light coupling inlet, the sealing cavity is filled with liquid high-refractive-index medium, and the liquid high-refractive-index medium is in direct contact with the light coupling inlet; the sealing cavity is provided with a coupling lens group, and the coupling lens group couples light rays into the sealing cavity;

when the refractive index of the liquid high refractive index medium is n and the maximum incident angle of the light incident into the light coupling port is θ, the numerical aperture NA of the light coupling port is expressed as: na=n.sinθ.

In one embodiment, the light coupling port is further provided with a coupling grating.

In one embodiment, the liquid high refractive index medium is deionized water, carbon disulfide, carbon tetrachloride, chloroform, or glycerol.

Another aspect of the present utility model provides a near-eye display device including: the optical waveguide, the sealing cavity, the coupling lens, the display panel and the adjustable-focus lens group; the optical waveguide is provided with a light coupling inlet, and a coupling-in reflecting surface is arranged in the optical waveguide corresponding to the light coupling inlet;

the sealing cavity is arranged at the light coupling inlet, and is filled with liquid high-refractive-index medium which is in direct contact with the light coupling inlet;

the sealing cavity is provided with a coupling lens group, and the coupling lens group couples light rays into the sealing cavity;

the display panel is provided with a pixel array, and the generated image is input to the coupling lens group through the adjustable-focus lens group.

In one embodiment, the liquid high refractive index medium is deionized water, carbon disulfide, carbon tetrachloride, chloroform, or glycerol.

In one embodiment, the display panel uses Micro-LEDs or Micro-OLED display panels.

One or more embodiments of the present utility model may have the following advantages over the prior art:

according to the utility model, the high refractive index medium is arranged at the entrance and exit of the optical waveguide, so that the numerical aperture of the optical waveguide light coupling port is improved, and therefore, higher-order diffraction light can pass through the coupling port more, and the resolution of image display is improved.

Additional features and advantages of the utility model will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the utility model. The objectives and other advantages of the utility model will be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings.

Drawings

The accompanying drawings are included to provide a further understanding of the utility model, and are incorporated in and constitute a part of this specification, illustrate the utility model and together with the embodiments of the utility model, serve to explain the utility model, without limitation to the utility model.

FIG. 1 is a schematic diagram of the structure of the present utility model;

FIG. 2 is a schematic cross-sectional view of the present utility model;

Detailed Description

The present utility model will be described in further detail with reference to the accompanying drawings, in order to make the objects, technical solutions and advantages of the present utility model more apparent.

Example 1

As shown in fig. 1, the optical waveguide device of the present embodiment includes an optical waveguide 1, a light coupling port 2 is provided in the optical waveguide 1, and a coupling-in reflecting surface 3 is provided in the optical waveguide 1 corresponding to the light coupling port 2.

In this embodiment, a sealed cavity 4 is disposed at the light coupling port 2, and the sealed cavity 4 is filled with a liquid high refractive index medium, where the liquid high refractive index medium is in direct contact with the light coupling port 2. The liquid high refractive index medium includes, but is not limited to, deionized water, carbon disulfide, carbon tetrachloride, chloroform, glycerol, and the like.

A coupling lens 5 is arranged on the sealing cavity 4, and the coupling lens 5 couples light into the sealing cavity 4.

In this embodiment, when the refractive index of the liquid high refractive index medium is n and the maximum incident angle of the light incident into the light coupling port 2 is θ, the numerical aperture NA of the light coupling port 2 can be expressed as follows according to the rayleigh equation: na=n.sinθ. As can be seen from the above formula, by increasing the refractive index of the medium, the numerical aperture NA of the light coupling port 2 can be increased, so that the higher-order diffraction wave passes through the light coupling port 2, thereby improving the resolution of image display.

In this embodiment, deionized water is used as the high refractive index medium for example, and the refractive index of deionized water is 1.44. The maximum incident angle θ of the light beam of the optical system formed by the light beam coupling port 2 serving as the diaphragm and the coupling lens 5 is not changed due to the filling of the medium with high refractive index, and when no other medium is filled between the coupling lens 5 and the light beam coupling port 2, the numerical aperture NA of the light beam coupling port 2 is: na=sinθ. When deionized water is filled between the coupling lens 5 and the light coupling port 2, the numerical aperture NA of the light coupling port 2 is: na=1.44. Sinθ. It can be seen that by filling the high refractive index medium, the numerical aperture of the light coupling-in port 2 is increased by a factor of 1.44.

In this embodiment, the coupling lens 5 employs a biconvex focusing lens, and the parameters of the biconvex focusing lens are shown in table 1 below.

TABLE 1

When the physical diameter of the light coupling port 2 in the present embodiment is 100 μm, the maximum incident angle θ of the optical system composed of the light coupling port 2 and the coupling lens 5 can reach 78.6 °, and when the high refractive index medium is deionized water, the numerical aperture NA of the light coupling port 2 can reach 1.41.

In this embodiment, the light coupling port 2 is further provided with a coupling grating 6.

Example 2

The near-eye display device of the present embodiment as shown in fig. 2 includes: an optical waveguide 1, a sealed cavity 4, a coupling lens 5, a display panel 7 and an adjustable focus lens group 8. Wherein, the optical waveguide 1 is provided with a light coupling port 2, and the optical waveguide 1 is provided with a coupling reflection surface 3 corresponding to the light coupling port 2.

The sealing cavity 4 is arranged at the light coupling opening 2, and the sealing cavity 4 is filled with a liquid high-refractive-index medium which is in direct contact with the light coupling opening 2. The liquid high refractive index medium includes, but is not limited to, deionized water, carbon disulfide, carbon tetrachloride, chloroform, glycerol, and the like.

A coupling lens 5 is arranged on the sealing cavity 4, and the coupling lens 5 couples light into the sealing cavity 4.

The display panel 7 is a display panel having an array of pixels, and the generated image is input to the coupling lens 5 through the adjustable-focus lens group 8. The display panel 7 may alternatively use a Micro-LED or Micro-OLED display panel.

The adjustable lens group 8 in this embodiment employs MIE-20-1064 adjustable lens modules from Diffratec Optics. The adjustable focusing range is-75 to mm to infinity; + mm to infinity; diopter adjustable range: -13.2 to +13.2dpt; the clear aperture is 20mm.

The above description is only a specific embodiment of the present utility model, and the scope of the present utility model is not limited thereto, and any person skilled in the art should modify or replace the present utility model within the technical specification described in the present utility model.

Claims (6)

1. An optical waveguide device for a near-eye display, the optical waveguide device comprising: the optical waveguide is provided with a light coupling inlet, and a coupling-in reflecting surface is arranged in the optical waveguide corresponding to the light coupling inlet; a sealing cavity is arranged at the light coupling inlet, the sealing cavity is filled with liquid high-refractive-index medium, and the liquid high-refractive-index medium is in direct contact with the light coupling inlet; the sealing cavity is provided with a coupling lens group, and the coupling lens group couples light rays into the sealing cavity;

when the refractive index of the liquid high refractive index medium is n and the maximum incident angle of the light incident into the light coupling port is θ, the numerical aperture NA of the light coupling port is expressed as: na=n.sinθ.

2. The optical waveguide device according to claim 1, wherein the light coupling port is further provided with a coupling grating.

3. The optical waveguide device of claim 1, wherein the liquid high refractive index medium is deionized water, carbon disulfide, carbon tetrachloride, chloroform, or glycerol.

4. A near-eye display device, the near-eye display device comprising: the optical waveguide, the sealing cavity, the coupling lens, the display panel and the adjustable-focus lens group; the optical waveguide is provided with a light coupling inlet, and a coupling-in reflecting surface is arranged in the optical waveguide corresponding to the light coupling inlet;

the sealing cavity is arranged at the light coupling inlet, and is filled with liquid high-refractive-index medium which is in direct contact with the light coupling inlet;

the sealing cavity is provided with a coupling lens group, and the coupling lens group couples light rays into the sealing cavity;

the display panel is provided with a pixel array, and the generated image is input to the coupling lens group through the adjustable-focus lens group.

5. The near-eye display device of claim 4, wherein the liquid high refractive index medium is deionized water, carbon disulfide, carbon tetrachloride, chloroform or glycerol.

6. The near-eye display device of claim 4, wherein the display panel uses a Micro-LED or Micro-OLED display panel.