CN214375582U - Display device, near-to-eye display apparatus, and optical waveguide element - Google Patents

Abstract

A display device, a near-eye display apparatus, and an optical waveguide element. A display device includes an image source and an optical waveguide element. The light guide element is positioned on the light emergent side of the image source, and the light emitted from the image source enters the light guide element and is emitted from the light emergent surface of the light guide element after being reflected for multiple times in the light guide element. The optical waveguide element comprises a plurality of first transflective portions which are arranged along a first direction, the first transflective portions are parallel to each other, one part of light rays which are transmitted to each of the first transflective portions in the first transflective portions is reflected by the first transflective portions to exit the light-emitting surface, and the other part of the light rays which are transmitted to each of the first transflective portions is transmitted through the first transflective portions and then is continuously transmitted in the optical waveguide element. The number of the first transflective portions is not less than 16, and the thickness of the optical waveguide element in the direction perpendicular to the light-emitting surface is not more than 0.5 mm. The thickness of the optical waveguide element can be made thin by providing a large number of first transflective portions in the optical waveguide element of the display device.

Description

Display device, near-to-eye display apparatus, and optical waveguide element

Technical Field

At least one embodiment of the present invention relates to a display device, a near-eye display apparatus, and an optical waveguide element.

Background

Currently, near-eye display devices (e.g., head mounted displays) include components such as an image source and optical elements, where the volume of the optical elements directly affects the volume of the near-eye display device. Therefore, near-eye display devices having features of small size, light weight, comfortable use, etc. are gaining favor of more and more users.

SUMMERY OF THE UTILITY MODEL

At least one embodiment of the present invention provides a display device, a near-eye display apparatus, and an optical waveguide element. The light waveguide element of the display device is provided with a large number of first transflective portions, so that the thickness of the light waveguide element can be thinner, the display effect is not influenced, and meanwhile, the light and thin of the display device are guaranteed.

An at least embodiment of the utility model provides a display device, include: an image source; the light guide element is positioned on the light emitting side of the image source, light emitted from the image source enters the light guide element, and is emitted from the light emitting surface of the light guide element after being reflected for multiple times in the light guide element. The optical waveguide element comprises a plurality of first transflective portions which are arranged along a first direction, the first transflective portions are parallel to each other, orthographic projections of adjacent first transflective portions on the light emitting surface are connected or partially overlapped, one part of light transmitted to each first transflective portion of the first transflective portions is reflected out of the light emitting surface by the first transflective portions, and the other part of the light transmitted to each first transflective portion is transmitted through the first transflective portion and then is continuously transmitted in the optical waveguide element; the number of the first transflective portions is not less than 16, and the thickness of the optical waveguide element in the direction perpendicular to the light emitting surface is not more than 0.5 mm.

For example, in some examples, the at least one first transflective portion includes a polarizing reflective surface configured to reflect light of a first polarization.

For example, in some examples, an included angle between each first transflective portion and the light emitting surface is 30 ° to 60 °.

For example, in some examples, the plurality of first transflective portions are arranged at equal intervals, the optical waveguide element includes a plurality of waveguide sub-elements arranged in a stack, one first transflective portion is included between adjacent waveguide sub-elements, and when a total thickness of the plurality of waveguide sub-elements in a direction perpendicular to a reflection surface of the first transflective portion is constant, the thickness of the optical waveguide element decreases as the number of the plurality of waveguide sub-elements increases.

For example, in some examples, the reflectance of the plurality of first transflective portions gradually increases or increases regionally in a propagation direction of the light entering the optical waveguide element.

For example, in some examples, the optical waveguide element further includes a plurality of second transflective portions arranged in a second direction, the plurality of second transflective portions being located on a light incident side of the plurality of first transflective portions, each of the second transflective portions being non-parallel to each of the first transflective portions, the plurality of second transflective portions being configured to reflect a portion of the light propagating into each of the second transflective portions toward the plurality of first transflective portions, the first direction and the second direction intersecting.

For example, in some examples, the display device further comprises: the optical array is positioned on the light emergent side of the image source and comprises a plurality of optical structures which are arranged in an array manner; and a coupling lens located between the optical array and the optical waveguide element. The image source comprises a plurality of sub-display areas, the sub-display areas correspond to the optical structures one to one, image light emitted by each sub-display area is configured to be emitted from the corresponding optical structure and enters the coupling lens, and light emitted by the coupling lens enters the optical waveguide element.

For example, in some examples, the display device further includes a light conversion element located at a light entrance side of the light guide element. The light conversion element comprises a light splitting part and a polarization conversion part; the light splitting part is positioned on one side of the image source facing the optical waveguide element and is configured to split image light emitted by the image source into the first polarized light and the second polarized light with different polarization states; the polarization conversion part is located on one side of the light splitting part facing the optical waveguide element and is configured to convert the second polarized light into the first polarized light, and the first polarized light is configured to be incident into the optical waveguide element and reflected out of the light emitting surface by the polarization reflection surface.

At least one embodiment of the utility model provides a near-to-eye display device, including any display device of the aforesaid.

At least one embodiment of the present invention provides an optical waveguide element, including a plurality of first transflective portions arranged along a first direction, and the first transflective portions are parallel to each other, and orthographic projections of adjacent first transflective portions on the light emitting surface are connected or partially overlapped, wherein the optical waveguide element includes a light emitting surface, a part of light transmitted to each of the first transflective portions in the first transflective portions is reflected by the first transflective portions out of the light emitting surface, and another part of light transmitted to each of the first transflective portions is transmitted through the first transflective portions and then continues to be transmitted in the optical waveguide element; the number of the first transflective portions is not less than 16, and the thickness of the optical waveguide element in the direction perpendicular to the light emitting surface is not more than 0.5 mm.

Drawings

In order to illustrate the technical solutions of the embodiments of the present invention more clearly, the drawings of the embodiments will be briefly described below, and it is obvious that the drawings in the following description only relate to some embodiments of the present invention, and are not intended to limit the present invention.

Fig. 1 is a schematic partial cross-sectional structure diagram of a display device according to an embodiment of the present invention;

FIG. 2 is a schematic view of a stacked structure including a plurality of waveguide subelements and a plurality of first transflective portions;

fig. 3 is a schematic partial structure diagram of a display device according to an example of the present invention;

fig. 4 is a schematic partial structure diagram of a display device according to an example of the present invention;

fig. 5 is a schematic view of a partial structure of a display device according to another example of the present invention; and

fig. 6 is a schematic partial cross-sectional structure diagram of a display device according to another example of the present invention.

Detailed Description

In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the drawings of the embodiments of the present invention are combined below to clearly and completely describe the technical solution of the embodiments of the present invention. It is to be understood that the embodiments described are only some of the embodiments of the present invention, and not all of them. All other embodiments, which can be obtained by a person skilled in the art without any inventive work based on the described embodiments of the present invention, belong to the protection scope of the present invention.

Unless defined otherwise, technical or scientific terms used herein shall have the ordinary meaning as understood by those of ordinary skill in the art to which the invention belongs. The use of "first," "second," and similar terms in the description herein do not denote any order, quantity, or importance, but rather the terms are used to distinguish one element from another. The word "comprising" or "comprises", and the like, means that the element or item listed before the word covers the element or item listed after the word and its equivalents, but does not exclude other elements or items.

The utility model provides a display device, near-to-eye display device and optical waveguide component. A display device includes an image source and an optical waveguide element. The light guide element is positioned on the light emergent side of the image source, and the light emitted from the image source enters the light guide element and is emitted from the light emergent surface of the light guide element after being reflected for multiple times in the light guide element. The optical waveguide element comprises a plurality of first transflective portions, one part of the light transmitted to each of the first transflective portions in the plurality of first transflective portions is reflected by the first transflective portions to exit the light exit surface, and the other part of the light transmitted to each of the first transflective portions is transmitted by the first transflective portions and then is continuously transmitted in the optical waveguide element. The number of the first transflective portions is not less than 16, and the thickness of the optical waveguide element in the direction perpendicular to the light-emitting surface is not more than 0.5 mm. The light waveguide element of the display device is provided with a large number of first transflective portions, so that the thickness of the light waveguide element can be thinner, the display effect is not influenced, and meanwhile, the light and thin of the display device are guaranteed.

The display device, the near-eye display apparatus, and the optical waveguide element according to the embodiments of the present invention are described below with reference to the drawings.

Fig. 1 is a schematic partial cross-sectional structure diagram of a display device according to an embodiment of the present invention. As shown in fig. 1, the display device includes an image source 100 and an optical waveguide element 200. The optical waveguide device 200 is located at the light emitting side of the image source 100, and the light emitted from the image source 100 is configured to enter the optical waveguide device 200, and is reflected multiple times in the optical waveguide device 200 and then emitted from the light emitting surface of the optical waveguide device 200. The optical waveguide element 200 includes a plurality of first transflective portions 210, a portion of the light transmitted to each of the first transflective portions 210 in the plurality of first transflective portions 210 is reflected by the first transflective portion 210 to exit the light exit surface 201, and another portion of the light transmitted to each of the first transflective portions 210 is transmitted through the first transflective portion 210 and then continuously transmitted in the optical waveguide element 200. The number of the first transflective portions 210 is not less than 16, and the thickness of the optical waveguide element 200 in a direction perpendicular to the light emitting surface 201 (Y direction shown in fig. 1) is not more than 0.5 mm. The light waveguide element of the display device is provided with a large number of first transflective portions, so that the thickness of the light waveguide element can be reduced, the display effect is not influenced, and the display device is reduced in weight.

For example, fig. 1 schematically shows that the light incident surface and the light emitting surface of the optical waveguide device 200 are located on the same side, that is, both are located on the side of the optical waveguide device 200 facing the image source 100, but not limited thereto, the light incident surface and the light emitting surface of the optical waveguide device may also be located on both sides of the optical waveguide device.

For example, as shown in fig. 1, the optical waveguide element 200 further includes a waveguide medium 220, and the light emitted from the image source 100 enters the waveguide medium 220 and propagates in the waveguide medium 220 by total reflection.

For example, the refractive index of the waveguide medium 220 is n1, the refractive index of the optically thinner medium (e.g., air) other than the waveguide medium 220 is n2, and the incident angle of the light entering the waveguide medium 220 is not less than the critical angle arcsin of total reflection (n2/n1), then the light satisfies the total reflection condition. For example, the waveguide medium 220 is made of a material that can perform the function of a waveguide, typically a transparent material with a refractive index greater than 1. For example, the material of the waveguide medium 220 may include one or more of silicon dioxide, lithium niobate, high molecular polymer, glass, and the like.

For example, the optical waveguide element 200 includes two first and second main surfaces 21 and 22 opposite to each other, and the plurality of first transflective portions 210 are located between the first and second main surfaces 21 and 22. For example, two main surfaces of the optical waveguide element 200 are parallel to each other, and the distance between the two main surfaces is the thickness of the optical waveguide element 200. For example, at least a portion of both major surfaces of optical waveguide element 200 are both major surfaces of waveguide medium 220. For example, the light incident into the optical waveguide device 200 propagates by total reflection on the first main surface and the second main surface, but there may be partial non-total reflection, such as specular reflection.

For example, as shown in fig. 1, the light totally reflected to each first transflective portion 210 is transmitted and reflected on the first transflective portion 210. For example, a part of the light incident on the surface of the first transflective portion 210 is reflected by the first transflective portion 210 out of the optical waveguide element 200, and the part of the light exits from the light exiting surface 201 of the optical waveguide element 200, for example, towards the user 10; another part of the light incident on the surface of the first transflective portion 210 is transmitted by the first transflective portion 210, then continuously propagates to the next first transflective portion 210 by total reflection, and is transmitted and reflected on the next first transflective portion 210, and the transmitted light continuously propagates to one first transflective portion 210 farthest from the image source 100 by total reflection (for example, the light sequentially passes through the transmission of the plurality of first transflective portions until reaching the one first transflective portion farthest from the image source). For example, all or part of the light rays propagating to a first transflective portion 210 farthest from the image source 100 may be reflected by the first transflective portion 210.

For example, as shown in fig. 1, the plurality of first transflective portions 210 are parallel to each other, and an included angle between each first transflective portion 210 and the light emitting surface 201 is 30 ° to 60 °. For example, an included angle between each first transflective portion 210 and the light emitting surface 201 may be 40 ° to 50 °. The included angle between each first transflective portion 210 and the light emitting surface 201 is 45 °. The above "parallel" may include completely parallel and substantially parallel, i.e., the included angle between the reflective surfaces of any two first transflective portions is not more than 5 °.

In the design of a typical arrayed optical waveguide element, it is considered that the larger the number of first transflective portions, the larger the cumulative error of production, and therefore, the number of first transflective portions in a typical arrayed optical waveguide does not exceed 7. In an embodiment of the present invention, by reducing the thickness of a single first transflective portion while increasing the number of first transflective portions, the first transflective portions can be kept parallel to each other when the number of first transflective portions is not less than 16, while the thickness of the monolithic optical waveguide element can be reduced.

For example, on the premise of controlling the accumulated error in the manufacturing process within a certain degree, the number of the first transflective portions in the optical waveguide element may be set as large as possible to achieve the lightness and thinness of the optical waveguide element, for example, the number of the first transflective portions 210 may be set to 16 to 25; for example, the number of the plurality of first transflective portions 210 may be set to be 20 to 30.

For example, as shown in fig. 1, the plurality of first transflective portions 210 are arranged at equal intervals. For example, as shown in fig. 1, orthographic projections of adjacent first transflective portions 210 on the light emitting surface 201 are connected or partially overlapped. For example, the embodiment of the present invention schematically illustrates that the orthographic projections of the adjacent first transflective portions 210 on the light emitting surface 201 meet each other, so that a dark region without light can be avoided between the two first transflective portions 210. But not limited thereto, the orthographic projections of the adjacent first transflective portions on the light emitting surface can be partially overlapped to avoid the weakening of the light at the edge of the first transflective portion, and the light emitting can be more uniform through the overlapping of the first transflective portions.

For example, as shown in FIG. 1, the first transflective portion 210 may be disposed in the waveguide medium 220 by plating or pasting.

For example, as shown in fig. 1, the optical waveguide element 200 includes a plurality of waveguide sub-elements 20 arranged in a stack, for example, the plurality of waveguide sub-elements 20 may be arranged in a first direction (i.e., the X direction shown in fig. 1), and one first transflective portion 210 may be included between adjacent waveguide sub-elements 20, for example, the plurality of first transflective portions 210 may be arranged in the first direction. For example, the surfaces of the waveguide sub-elements 20 that are attached to each other are parallel to each other.

For example, as shown in fig. 1, a portion of the waveguide medium 220 away from the image source 100 may be divided into a plurality of cylinders (i.e., waveguide subelements 20) with a parallelogram-shaped cross section (i.e., a cross section parallel to the XY plane shown in fig. 1), a first transflective portion 210 is disposed between the spliced cylinders, a medium between adjacent first transflective portions 210 may be the waveguide medium 220, and the first transflective portions 210 are configured to couple a portion of light out of the optical waveguide element by reflecting a total reflection condition that destroys the portion of light. Of course, the embodiment of the present invention is not limited to the first transflective portion being disposed on the surface of the waveguide sub-element in a plating or pasting manner, and the first transflective portion may also be a surface where two adjacent waveguide sub-elements are pasted to each other.

For example, fig. 2 is a schematic view of a stacked structure including a plurality of waveguide subelements and a plurality of first transflective portions. As shown in fig. 2, when the total thickness H of the plurality of waveguide sub-elements 20 in the direction perpendicular to the reflection surface of the first transflective portion 210 is constant, the thickness T of the optical waveguide element 200 decreases as the number of the plurality of waveguide sub-elements 20 increases.

For example, if the thicknesses h of the waveguide sub-elements 20 are all equal, the thickness h of each waveguide sub-element 20 and the thickness T of the optical waveguide element 200 satisfy the relationship: t ═ a × h, where a is a coefficient, and a is fixed during the design of the optical waveguide element. When the width of the optical waveguide element is constant, the total thickness H of the stack of the plurality of waveguide sub-elements 20 is constant, and the thickness H of the waveguide sub-element 20, and thus the thickness T of the optical waveguide element, can be adjusted by adjusting the number of waveguide sub-elements 20. For example, the greater the number of waveguide sub-elements 20 (i.e., the greater the number of first transflective portions 210), the smaller the thickness h of each waveguide sub-element 20, and thus the thinner the thickness of the optical waveguide element. For example, if the number of the first transflective portions 210 is set to not less than 16, the thickness of the optical waveguide element is not more than 0.5 mm.

For example, the thickness of the optical waveguide element may be further reduced by increasing the number of the first transflective portions 210. For example, the thickness of the optical waveguide element may be 0.1 to 0.4 mm. For example, the thickness of the optical waveguide element may be 0.2 to 0.5 mm.

For example, the image source 100 may be an image source in a micro-projector light machine, such as an organic light emitting diode display source. Embodiments of the present invention are not limited thereto, and the image source may also be any other suitable type of display source, for example, an LCD image display source, etc. For example, the image source 100 can include a monochromatic light source, which ultimately can form a monochromatic image, or a color-mixed light source, which can form a color image, such as a red monochromatic light source, a green monochromatic light source, a blue monochromatic light source, or a white color-mixed light source. For example, the image source 100 includes a light source that may be a laser light source or a Light Emitting Diode (LED) light source. For example, the image source 100 may include one light source or a plurality of light sources.

For example, as shown in fig. 1, the optical waveguide element 200 further includes a light incoupling part 230 located at the light incident side of the first transflective part 210, configured such that light entering the optical waveguide element 200 satisfies a total reflection condition to propagate in the waveguide medium 220 by total reflection. The embodiment of the utility model provides a be not limited to the optical waveguide component and include optical coupling portion, for example, the optical waveguide component can also not include optical coupling portion, and when the angle of the light of incidenting the waveguide medium satisfied the total reflection condition, this light can realize the total reflection propagation in the waveguide medium.

For example, the light incoupling part 230 may include at least one of a surface grating, a volume grating, a blazed grating, a prism and a reflective structure, and couples the light emitted from the image source 100 into the waveguide medium 220 to satisfy the total internal reflection condition and thus be guided by at least one of reflection, refraction and diffraction effects.

For example, fig. 3 is a schematic partial structure diagram of a display device according to an example of the present invention. As shown in fig. 3, the at least one first transflective portion 210 includes a polarizing reflective surface 211, the polarizing reflective surface 211 configured to reflect light of a first polarization. Fig. 3 schematically illustrates that each of the first transflective portions includes a polarizing reflective surface.

For example, the light entering the optical waveguide element 200 may include a first polarized light and a second polarized light, the polarization reflection surface 211 is configured to have a reflectivity for the first polarized light greater than a reflectivity for the second polarized light and a transmissivity for the second polarized light greater than a transmissivity for the first polarized light, whereby the first transflective portion may gradually reflect the first polarized light out of the optical waveguide element.

The light entering the optical waveguide element may be unpolarized light or may be polarized light in two polarization states. By "unpolarized light" is meant light from the image source that has multiple polarization properties at the same time but does not exhibit unique polarization properties, for example, light from the image source may be combined from two orthogonal polarization states, i.e., unpolarized light from the image source may be split into two orthogonal polarization states.

For example, the polarization reflective surface 211 may be a brightness enhancement film having a high reflectivity for one polarization and a high transmittance for another polarization (e.g., the polarization reflective surface may have a high reflectivity for S-polarized light and a high transmittance for P-polarized light), and the first transflective portion may utilize the selectivity of polarization transflective such that light is gradually reflected out of the optical waveguide element by the first transflective portion. For example, the polarization reflecting surface can be attached to the surface of the waveguide medium through transparent glue, so that the surface profile of the optical waveguide element can be corrected by utilizing the transparent glue, the processing requirement on the surface profile of the optical waveguide element is reduced, and the production cost is greatly reduced.

For example, the light entering the optical waveguide device 200 may also include only polarized light in one polarization state, for example, the first polarized light may be reflected by the first transflective portion 210, and the first transflective portion may reflect all the light entering the optical waveguide device out of the light exit surface as much as possible, so as to improve the brightness of the exit light and reduce the power consumption of the display device.

For example, fig. 4 is a schematic partial structure diagram of a display device according to an example of the present invention. As shown in fig. 4, the display device further includes a light conversion member 500 positioned at the light incident side of the light guide member 200. For example, the light conversion element 500 includes a spectroscopic part 510 and a polarization conversion part 520. The light splitting part 510 is located at a side of the image source 100 facing the optical waveguide element 200, and is configured to split the image light emitted from the image source 100 into first polarized light L1 and second polarized light L2 having different polarization states. The polarization conversion unit 520 is located on the light incident side of the optical waveguide device 200, and is configured to convert the split second polarized light L2 into the first polarized light L1 ', and the split first polarized light L1 and the converted first polarized light L1' are configured to enter the optical waveguide device 200 and to be reflected by the polarization reflection surface 211 to exit the light exit surface 201. The embodiment of the utility model provides a through the light conversion who sends the non-polarization state of image source for can be by the polarized light of a polarization state of polarization plane reflection, can improve the utilization ratio of the light that the image source sent.

For example, as shown in fig. 4, the light splitting part 510 may have a function of transmitting light of one characteristic and reflecting light of another characteristic, for example, the light splitting part 510 may have a function of transmitting light of one polarization state (for example, the first polarized light L1) and reflecting light of another polarization state (for example, the second polarized light L2), and the light splitting part 510 may implement beam splitting by using the transflective characteristic. For example, the first polarized light and the second polarized light may be linearly polarized light having different polarization directions, but are not limited thereto, and may be circularly polarized light having different rotation directions. The first polarized light and the second polarized light may be interchanged.

For example, the light splitting part 510 may be a transflective film, and the beam splitting effect is achieved by transmitting a part of light and reflecting another part of light. For example, the transflective film may be an optical film having a polarizing transflective function, and the optical film may split an unpolarized light ray into two mutually orthogonally polarized light rays by means of transmission and reflection. For example, the optical film may be formed by combining a plurality of film layers having different refractive indexes in a certain stacking order, and the material of the film layers may include an inorganic dielectric material or a polymer material.

For example, fig. 4 schematically shows that polarized light transmitted by the spectroscopic unit 510 is directly incident on the optical waveguide device 200, and polarized light reflected by the spectroscopic unit 510 is converted in polarization direction by the polarization conversion unit 520 and then incident on the optical waveguide device 200. However, the polarization direction of the polarized light transmitted by the splitting unit may be converted by the polarization conversion unit and then the converted polarized light may be incident on the optical waveguide device.

For example, as shown in fig. 4, the polarization conversion unit 520 may be a phase retarder film, and the light emitted from the phase retarder film to the optical waveguide element 200 may be the first polarized light L1' by rotating the polarization direction of the second polarized light L2 incident thereon by 90 degrees. For example, the polarization conversion part 520 may be an 1/2 wave plate.

For example, as shown in fig. 4, the light conversion element 500 may further include a direction changing portion 530, and the direction changing portion 530 is configured to reflect the polarized light of one polarization state after the beam split incident to the direction changing portion 530 to the polarization conversion portion 520. For example, as shown in fig. 4, the direction changing section 530 is configured to reflect the split second polarized light L2 incident on the direction changing section 530 to the polarization conversion section 520. The embodiment of the utility model provides a be not limited to this, direction change portion also can be located between polarization conversion portion and the optical waveguide component, and at this moment, the second polarized light through light splitting portion reflection converts first polarized light into behind polarization conversion portion, and this first polarized light incides to optical waveguide component 200 behind direction change portion redirecting.

For example, the direction changing unit 530 may be a reflecting element for reflecting the polarized light of one polarization state, for example, the second polarized light L2, split from the beam splitting unit 510 to the polarization conversion unit 520.

For example, the direction changing part 530 may be a general reflective plate, such as a reflective plate made of a material including metal or glass; a reflective film having a characteristic of reflecting, for example, the second polarized light L2 may be plated or attached on the substrate. For example, the direction changing unit 530 may have transflective characteristics similar to those of the transflective film included in the spectroscopic unit 510, that is, characteristics of reflecting the second polarized light L2 and transmitting the first polarized light L1.

For example, as shown in fig. 4, the image source 100 emits unpolarized light, the beam splitting part 510 reflects S-polarized light (e.g., the second polarized light L2) and transmits P-polarized light (e.g., the first polarized light L1), and the direction changing part 530 may reflect the S-polarized light. S polarized light in the unpolarized light emitted from the image source 100 is reflected by the beam splitter 510, the reflected S polarized light is reflected by the direction changing unit 530 and then emitted to the polarization conversion unit 520, and the S polarized light is converted into P polarized light by the polarization conversion unit 520, so that the unpolarized light emitted from the image source is converted into P polarized light. Of course, the embodiment of the present invention is not limited to this, and may also be that the light conversion element converts all the unpolarized light emitted from the image source into S polarized light.

For example, as shown in fig. 1 to 4, the reflectance of the plurality of first transflective portions 210 gradually increases or gradually increases in a region in the propagation direction of the light entering the optical waveguide device 200. For example, as shown in fig. 1 to 4, the plurality of first transflective portions 210 are arranged along a light total reflection propagation direction, which may refer to a direction of the whole (macroscopic) light propagation, for example, a direction opposite to a direction indicated by an arrow in the X direction shown in fig. 1, and a light entering the optical waveguide element 200 is totally internally reflected at both main surfaces of the waveguide medium 220, so that the light is entirely propagated to the first transflective portions 210 in a direction opposite to the direction indicated by the arrow in the X direction.

For example, as shown in fig. 1 to 4, the plurality of first transflective portions 210 are uniformly arranged and have gradually increased reflectivity along a direction in which light is totally reflected and propagates in the waveguide medium 220. For example, the first transflective portion 210 closer to the image source 100 has a smaller reflectivity. For example, the reflectivity of the first transflective portions sequentially arranged along the extending direction of the light emitting surface in the plurality of first transflective portions 210 gradually increases or gradually increases in a regional manner in the propagation direction of the light. For example, the regional increase may be two or more regions, and the reflectance of the first transflective portion is different and gradually increases in the different regions.

The uniform arrangement may refer to an arrangement in which adjacent first transflective portions are disposed such that orthographic projections thereof are contiguous to each other, or an arrangement in which adjacent first transflective portions are disposed such that orthographic projections thereof are partially overlapped. Since the light will be reflected out of the optical waveguide element gradually during the propagation process, the light intensity will be attenuated gradually, and therefore, by setting the transflective properties of the first transflective portions to be different, for example, the reflectivity of the first transflective portions gradually increases along the path of the total reflection propagation of the light, the intensity of the light reflected out of each first transflective portion can be relatively uniform.

For example, fig. 5 is a schematic view of a partial structure of a display device according to another example of the present invention. As shown in fig. 5, the display device further includes an optical array 300 and a coupling lens 400. The optical array 300 is located at the light exit side of the image source 100 and includes a plurality of optical structures 310 arranged in an array. For example, the plurality of optical structures 310 are arranged in a planar array perpendicular to the Y-direction. For example, the coupling lens 400 is located between the optical array 300 and the optical waveguide element 200. For example, as shown in fig. 5, the image source 100 includes a plurality of sub-display regions 110, and the plurality of sub-display regions 110 are arranged in a planar array perpendicular to the Y-direction. For example, the plurality of sub-display areas 110 and the plurality of optical structures 310 correspond one-to-one, i.e., the image source 100 includes the same number of sub-display areas 110 as the optical structures 310 included in the optical array 300, and one sub-display area 110 corresponds to one optical structure 310. The image light emitted from each sub-display region 110 is configured to exit from the corresponding optical structure 310 and enter the coupling lens 400, and the light exiting from the coupling lens 400 enters the optical waveguide device 200. For example, image light emitted from different sub-display regions 110 passes through different optical structures 310 and is incident on the coupling lens 400.

For example, the image source 100 includes a plurality of sub-display regions 110 that may be a plurality of different partial fields of view that divide the display region of the image source 100. Each sub-display area 110 forms a local field of view. For example, the different sub-display regions 110 are connected to each other to form a display region of the entire image source 100.

For example, the sub display region 110 may be a display unit capable of displaying different colors and brightness. For example, each display unit includes a plurality of sub-pixels of different colors, and by adjusting the light emission luminance of the sub-pixels of different colors, each display unit can be caused to display light of different colors and different luminances, so that the entire display area displays a color picture. For example, each display unit may include red, green, and blue sub-pixels, and light of different colors and different brightness may be displayed by mixing light emitted from the different color sub-pixels. Of course, each sub-display region may include only one sub-pixel, and each sub-display region may be regarded as a region where each sub-pixel is located.

For example, the light incident on the optical waveguide element 200 is collimated light. For example, each optical structure 310 may be a collimating optical channel configured to collimate image light incident to the optical structure. For example, each optical structure 310 may collimate image light from the image source 100, in which case the coupling lens 400 is configured such that collimated light incident to the coupling lens 400 remains parallel collimated light after passing through the coupling lens 400. The embodiment of the utility model provides a be not limited to this, optical structure also can be non-collimation optical channel, and at this moment, coupling lens is collimation coupling lens, and is configured to carry out the collimation from every optical structure focus to coupling lens's light.

For example, the plurality of optical structures may cooperate with the coupling lens, so that light beams emitted from different local fields of view (i.e., different sub-display regions) on the image source are focused by the corresponding optical structures to the optimal collimating and imaging position of the coupling lens relative to the light beam, and are collimated by the coupling lens, and then emitted from the coupling lens to the optical waveguide element to form a series of parallel lights in different directions.

For example, the optical array may include a multilayer optical array structure, each layer of the optical array structure including a face structure having an optical refraction function and at least one of a spherical surface, an aspherical surface, a free-form surface, and a flat surface.

Fig. 6 is a schematic partial cross-sectional structure diagram of a display device according to another example of the present invention. As shown in fig. 6, the optical waveguide element 200 further includes a plurality of second transflective portions 240 arranged along a second direction (i.e., a Z direction shown in the figure), the plurality of second transflective portions 240 are located at light incident sides of the plurality of first transflective portions 210, each second transflective portion 240 is not parallel to each first transflective portion 210, and the plurality of second transflective portions 240 are configured to reflect a part of the light rays propagating into the plurality of second transflective portions 240 toward the plurality of first transflective portions 210.

For example, fig. 6 schematically shows that the first direction and the second direction are perpendicular, but is not limited thereto, and the first direction and the second direction may intersect.

For example, as shown in fig. 6, each second transflective portion 240 may have the same characteristics as each first transflective portion 210, and thus, the description thereof is omitted. For example, the relative position relationship of the plurality of second transflective portions 240 may also be the same as the relative position relationship of the plurality of first transflective portions, and will not be described herein again.

For example, the number of the second transflective portions 240 may be the same as or different from the number of the first transflective portions 210.

For example, as shown in fig. 6, the optical waveguide element provided with the plurality of first transflective portions 210 and the optical waveguide element provided with the plurality of second transflective portions 240 may be an integrated structure, but not limited thereto, and the first transflective portions and the second transflective portions may be respectively provided in two optical waveguide elements separated from each other.

As shown in fig. 6, the image light emitted from the image source 100 is transmitted and reflected by the plurality of second transflective portions 240 to realize the expansion in one direction (e.g., the second direction), and the light reflected from the plurality of second transflective portions 240 to the plurality of first transflective portions 210 is transmitted and reflected by the plurality of first transflective portions 210 to realize the expansion in another direction (e.g., the first direction) of the light emitted from the light emitting surface of the optical waveguide element.

The display device provided by the example is provided with the two-dimensional array optical waveguide element, and can expand image light emitted from an image source in two directions, so that the field angle of the display device is enlarged under the condition that the volume of the display device is not increased as much as possible.

Another embodiment of the present invention provides an optical waveguide element, including a plurality of first transflective portions arranged along a first direction, wherein the first transflective portions are parallel to each other, and orthographic projections of adjacent first transflective portions on the light emitting surface are connected or partially overlapped, wherein the optical waveguide element includes a light emitting surface, a part of light transmitted to each of the first transflective portions in the first transflective portions is reflected by the first transflective portions out of the light emitting surface, and another part of light transmitted to each of the first transflective portions is transmitted through the first transflective portions and then continues to be transmitted in the optical waveguide element; the number of the first transflective portions is not less than 16, and the thickness of the optical waveguide element in the direction perpendicular to the light emitting surface is not more than 0.5 mm. It should be noted that the description of the optical waveguide element in the display device is applicable to the optical waveguide element, and the description of the structure and the technical effect thereof is not repeated.

Another embodiment of the present invention provides a near-to-eye display device, including the display device provided by any of the above examples.

For example, the utility model provides a near-eye display device can be for head mounted display or other augmented reality or virtual reality display device. The near-eye display device may comprise, for example, a mixed reality head-mounted display, such as microsoft's HoloLens.

For example, the near-eye display device may be AR glasses, the optical waveguide element may be mounted in the frame of the glasses (e.g., near the lenses), and the image source, the optical array, the coupling lens, and the light conversion element may be mounted in the arms of the glasses adjacent to the edges of the optical waveguide element. For example, the drive electronics for the image source may be mounted on the arm, and power supplies and the like may be connected to the arm by wires.

The following points need to be explained:

(1) in the drawings of the embodiments of the present invention, only the structures related to the embodiments of the present invention are referred to, and other structures may refer to general designs.

(2) Features of the present invention may be combined with each other in the same embodiment and in different embodiments without conflict.

The above description is only an exemplary embodiment of the present invention, and is not intended to limit the scope of the present invention, which is defined by the appended claims.

Claims (10)

1. A display device, comprising:

an image source;

an optical waveguide element located at the light exit side of the image source, wherein the light emitted from the image source is configured to enter the optical waveguide element and exit from the light exit surface of the optical waveguide element after being reflected for multiple times in the optical waveguide element,

the optical waveguide element comprises a plurality of first transflective portions which are arranged along a first direction, the first transflective portions are parallel to each other, orthographic projections of adjacent first transflective portions on the light emitting surface are connected or partially overlapped, one part of light transmitted to each first transflective portion of the first transflective portions is reflected out of the light emitting surface by the first transflective portions, and the other part of the light transmitted to each first transflective portion is transmitted through the first transflective portion and then is continuously transmitted in the optical waveguide element;

the number of the first transflective portions is not less than 16, and the thickness of the optical waveguide element in the direction perpendicular to the light emitting surface is not more than 0.5 mm.

2. The display device of claim 1, wherein at least one first transflective portion comprises a polarizing reflective surface configured to reflect light of a first polarization.

3. The display device according to claim 1, wherein an included angle between each first transflective portion and the light emitting surface is from 30 ° to 60 °.

4. The display device according to claim 1, wherein the plurality of first transflective portions are arranged at equal intervals, the optical waveguide element comprises a plurality of waveguide sub-elements arranged in a stack, and one of the first transflective portions is included between adjacent waveguide sub-elements.

5. The display device according to any one of claims 1 to 3, wherein the reflectance of the plurality of first transflective portions gradually increases or gradually increases regionally in a propagation direction of the light entering the light guide element.

6. The display device according to any one of claims 1 to 3, wherein the optical waveguide element further comprises a plurality of second transflective portions arranged in a second direction, the plurality of second transflective portions being located on a light-incident side of the plurality of first transflective portions, each of the second transflective portions being non-parallel to each of the first transflective portions, the plurality of second transflective portions being configured to reflect a part of the light propagating into each of the second transflective portions toward the plurality of first transflective portions, the first direction and the second direction intersecting.

7. A display device according to any one of claims 1 to 3, wherein the display device further comprises:

the optical array is positioned on the light emergent side of the image source and comprises a plurality of optical structures which are arranged in an array manner; and

a coupling lens located between the optical array and the optical waveguide element,

the image source comprises a plurality of sub-display areas, the sub-display areas correspond to the optical structures one to one, image light emitted by each sub-display area is configured to be emitted from the corresponding optical structure and enters the coupling lens, and light emitted by the coupling lens enters the optical waveguide element.

8. The display device of claim 2, further comprising a light conversion element located on a light entrance side of the light guide element,

wherein the light conversion element includes a spectroscopic portion and a polarization conversion portion;

the light splitting part is positioned on one side of the image source facing the optical waveguide element and is configured to split image light emitted by the image source into the first polarized light and the second polarized light with different polarization states;

the polarization conversion part is located on one side of the light splitting part facing the optical waveguide element and is configured to convert the second polarized light into the first polarized light, and the first polarized light is configured to be incident into the optical waveguide element and reflected out of the light emitting surface by the polarization reflection surface.

9. A near-eye display apparatus comprising the display device of any one of claims 1-8.

10. An optical waveguide component, comprising a plurality of first transflective portions arranged along a first direction, wherein the plurality of first transflective portions are parallel to each other, the optical waveguide component comprises a light-emitting surface, orthographic projections of adjacent first transflective portions on the light-emitting surface are connected or partially overlapped,

wherein a part of the light transmitted to each of the plurality of first transflective portions is reflected by the first transflective portion out of the light emitting surface, and another part of the light transmitted to each of the plurality of first transflective portions is transmitted through the first transflective portion and then continues to be transmitted in the optical waveguide element;

the number of the first transflective portions is not less than 16, and the thickness of the optical waveguide element in the direction perpendicular to the light emitting surface is not more than 0.5 mm.

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