Optical waveguide module and display device

Abstract

The utility model relates to the technical field of display equipment, in particular to an optical waveguide module, a waveguide body is provided with a first surface, a second surface and a side wall surface, the first surface and the second surface deviate from each other, the side wall surface is connected between the first surface and the second surface, the surface of the waveguide body is provided with a coupling-in area, a mounting area and a coupling-out area, and the coupling-in area is arranged on the first surface. Part of light is coupled out of the waveguide body through the coupling-out area according to the specified transmission direction to form image light, and part of light is transmitted to the installation area to form stray light. The installation area is arranged on the second surface and corresponds to the coupling-in area, and the light turning piece is arranged in the installation area and used for conducting stray light to the side wall face. The light-transmitting dodging piece is arranged on the side wall surface and is provided with a diffusion part used for diffusing stray light, the light absorption layer is arranged on the side, away from the side wall surface, of the light-transmitting dodging piece, and the diffusion part is arranged between the light absorption layer and the side wall surface. According to the optical waveguide module, heat can be prevented from being concentrated at a single position, and the heat dissipation performance of the device is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of display devices, and particularly relates to a light waveguide module and a display device. BACKGROUND

[0002] In the display technology of AR (Augmented Reality), when the light beams are transmitted in the waveguide, part of the light beams form stray light in the non-display area after penetrating the waveguide, for example, the stray light emitted through the side surface of the light waveguide, which affects the display effect. In order to reduce the stray light, in the conventional technology, an ink layer or the like light-absorbing member or light-blocking member is arranged at the light-leaking part (for example, the side wall) of the light waveguide to absorb or block the stray light.

[0003] However, due to the high heat of the light beams in the transmission process, the stray light has the characteristic of energy concentration when leaking, so that the heat is relatively concentrated when the light-absorbing layer or the light-blocking member absorbs / block the stray light, and the heat dissipation effect is not ideal. CONTENT OF THE UTILITY MODEL

[0004] Therefore, the embodiments of the present application provide a light waveguide module to solve the above technical problems.

[0005] In a first aspect, the embodiments of the present application provide a light waveguide module, which comprises a waveguide body, a coupling-in area, a coupling-out area, a mounting area, a light folding member, a light-transmitting and light-uniformizing member, and a light-absorbing layer. The waveguide body has a first surface, a second surface, and a side wall surface, the first surface and the second surface are opposite to each other, and the side wall surface is connected between the first surface and the second surface. The surface of the waveguide body is provided with the coupling-in area, the mounting area, and the coupling-out area, the coupling-in area is arranged on the first surface, part of the light beams is coupled into the waveguide body through the coupling-in area, part of the light rays is coupled out of the waveguide body through the coupling-out area according to a specified transmission direction to form image light, and part of the light rays propagates to the mounting area to form stray light. The mounting area is arranged on the second surface and corresponds to the coupling-in area, the light folding member is arranged in the mounting area, and the light folding member is used to conduct the stray light to the side wall surface. The light-transmitting and light-uniformizing member is arranged on the side wall surface, the light-transmitting and light-uniformizing member has a diffusion part for diffusing the stray light. The light-absorbing layer is arranged on the side of the light-transmitting and light-uniformizing member away from the side wall surface, and the diffusion part is arranged between the light-absorbing layer and the side wall surface.

[0006] In some embodiments, the projection profile of the light folding member and the projection profile of the coupling-in area at least partially coincide when projected in a direction perpendicular to the first surface.

[0007] In some embodiments, the light folding member comprises a prism, and the refractive index of the prism is equal to the refractive index of the waveguide body.

[0008] In some embodiments, the light folding member comprises a grating, and the grating is one of an inclined grating or a blazed grating.

[0009] In some embodiments, the diffusion portion is a cavity formed based on the light-transmitting homogenizing member, and at least part of the stray light is reflected by the wall of the cavity multiple times before propagating to the light-absorbing layer when the stray light propagates into the cavity. In some embodiments, the light-transmitting homogenizing member comprises a first side portion and a second side portion arranged apart from each other, the cavity is arranged between the first side portion and the second side portion, the first side portion is attached to the side wall, and the light-absorbing layer is arranged on the side of the second side portion away from the cavity.

[0010] In some embodiments, the first side portion is provided with a first reflective microstructure on the side facing the cavity, and the second side portion is provided with a second reflective microstructure on the side facing the cavity, and the reflectivity of the first reflective microstructure is greater than the reflectivity of the second reflective microstructure.

[0011] In some embodiments, the first reflective microstructure comprises a microlens array and / or a reflective coating.

[0012] In some embodiments, the second reflective microstructure comprises a microlens array and / or a reflective coating.

[0013] In some embodiments, the first side portion is provided with a light guide portion for receiving stray light propagating from the light-bending member and conducting the stray light into the cavity, and the light guide portion is not provided with the first reflective microstructure.

[0014] In some embodiments, the coupling-out region is arranged on the side of the coupling-in region along the positive direction of the specified transmission direction, and the light guide portion is arranged on the side of the coupling-out region along the negative direction of the specified transmission direction.

[0015] In some embodiments, the light guide portion is a through hole, the light guide portion is in communication with the cavity, and the first reflective microstructure is arranged around the outer periphery of the through hole.

[0016] In some embodiments, the light-transmitting homogenizing member is arranged apart from the side wall, the cavity is arranged between the light-transmitting homogenizing member and the side wall, the light-absorbing layer is arranged on the side of the light-transmitting homogenizing member away from the cavity, and the light-transmitting homogenizing member is provided with a reflective microstructure on the side facing the cavity.

[0017] In some embodiments, the diffusion portion comprises a first transreflective layer and a second transreflective layer, the first transreflective layer and the second transreflective layer are arranged in a laminated manner by being attached to each other between the light-absorbing layer and the side wall, the surfaces of the first transreflective layer and the second transreflective layer facing each other are provided with a reflective microstructure, and the refractive index of the first transreflective layer is equal to the refractive index of the second transreflective layer. In some embodiments, the number of side walls is a plurality, the plurality of side walls are connected end to end to form an outer peripheral wall of the waveguide body, and the light-transmitting homogenizing member is arranged around the outer periphery of the waveguide body so that the homogenizing portion is arranged outside the plurality of side walls.

[0018] In some embodiments, the light-absorbing layer includes an ink layer, and the thickness of the ink layer is greater than or equal to 1 mm and less than or equal to 3 mm.

[0019] In a second aspect, the embodiments of the present application provide a display device, which comprises a light source for forming a light beam, and the light waveguide module according to any one of the above embodiments, the light waveguide module being located on the light path of the light beam.

[0020] Compared with the prior art, the embodiments of the present application provide a light waveguide module, which is provided with a coupling-in area, a coupling-out area, and a mounting area, wherein the mounting area and the coupling-in area are located on the first surface and the second surface of the waveguide body and correspond to each other. The light folding member arranged in the mounting area can transmit the stray light propagating to the mounting area to the side wall surface, thereby effectively reducing the interference of the stray light leaking from the front on the display area and improving the display effect and the use safety. In addition, the light-transmitting and light-uniformizing member is arranged on the side wall surface and is used for transmitting light to uniformly light the stray light conducted to the side wall surface, thereby improving the uniformity of the distribution of the light beam on the side wall surface and avoiding the heat being concentrated in a single position due to the local concentration of the stray light, which is conducive to the dispersion of the heat, improves the heat dissipation efficiency, and reduces the overall temperature. Further, the light-transmitting and light-uniformizing member has a diffusion part, and the stray light can be diffused in the diffusion part after being uniformly lighted in the side wall part, which can further improve the uniformity of the distribution of the light beam and additionally increase the heat distribution area of the light beam, so that the overall temperature is further reduced. Meanwhile, the light waveguide module further comprises a light-absorbing layer, which can absorb the stray light diffused after passing through the diffusion part, prevent the stray light from leaking from the side of the diffusion part, and further reduce the interference on the environment. BRIEF DESCRIPTION OF DRAWINGS

[0021] In order to more clearly illustrate the technical solutions of the present application, the following will briefly introduce the drawings needed to be used in the embodiments. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without any creative effort.

[0022] Figure 1 is a schematic diagram of a longitudinal cross-sectional structure of a light waveguide module provided by an embodiment of the present application along the thickness direction.

[0023] Figure 2 is a schematic diagram of a structure of a display device provided by an embodiment of the present application.

[0024] Figure 3 is Figure 1 is a schematic diagram of a transverse cross-sectional structure of the light waveguide module shown in the above along the length or width direction.

[0025] Figure 4 is Figure 1The structure diagram of the light-transmitting and light-uniformizing member and the light-absorbing layer of the light waveguide module in another embodiment is shown.

[0026] Figure 5 is Figure 1 The structure diagram of the light-transmitting and light-uniformizing member and the light-absorbing layer of the light waveguide module in another embodiment is shown.

[0027] Figure 6 is Figure 1 The structure diagram of the light-transmitting and light-uniformizing member and the light-absorbing layer of the light waveguide module in another embodiment is shown.

[0028] Figure 7 is Figure 1 The structure diagram of the light-transmitting and light-uniformizing member and the light-absorbing layer of the light waveguide module in another embodiment is shown.

[0029] Figure 8 is a longitudinal cross-sectional structure diagram of a light waveguide module according to another embodiment of the present application.

[0030] Figure 9 is Figure 8 The transverse cross-sectional structure diagram of the light waveguide module is shown. DETAILED DESCRIPTION

[0031] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the scope of protection of the present application.

[0032] It should be noted that when an element / component is referred to as being “fixed” to another element / component, it can be directly on the other element / component or there can be an intermediate element / component. When an element / component is referred to as being “connected” to another element / component, it can be directly connected to the other element / component or there can be an intermediate element / component; at the same time, when an element / component is referred to as being “connected” to another element / component, it can be integrally formed or assembled with the other element / component. When an element / component is referred to as being “provided” to another element / component, it can be directly provided on the other element / component or there can be an intermediate element / component.

[0033] Unless otherwise defined, 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 application belongs. The terminology used in the description herein is for describing particular embodiments only and is not intended to be limiting of the application. As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items.

[0034] Referring now to the drawings Figure 1 The embodiments of the present application provide a light waveguide module 100, which includes a waveguide body 10, a light folding member 20, a light transmission and homogenizing member 30, and a light absorbing layer 40. The light waveguide module 100 projects light carrying virtual information (such as images, text, animations, etc.) into the real field of view of a user in real time by using optical principles such as total reflection or diffraction, thereby enhancing the user's perception and interaction experience with the real world. The light waveguide device 100 can be applied to display devices, such as vehicle-mounted head-up display systems, near-eye display devices, etc., and the embodiments are not specifically limited in this regard.

[0035] Referring now to the drawings Figure 1 and Figure 2 As an example, the embodiments of the present application provide a display device 200 with a light waveguide module 100, which can be AR glasses. The AR glasses can include a support 201 and a frame 202 connected to the support 201, and the light waveguide module 100 and a lens assembly (not shown in the figure) are arranged in the frame 202 to project virtual images into the user's eyes while ensuring that the user can see the real world. The display device 200 can include a light source 210 arranged adjacent to the light waveguide module 100, which is used to form a light beam, and the light waveguide module 100 is arranged on the propagation path of the light beam to receive the light beam. As a specific example, the light source 210 can be arranged on the support 201, and the light beam can be conducted to the light waveguide module 100 through the lens assembly.

[0036] The light source 210 can specifically include a light engine, which is used to provide a light source for the light waveguide module 100. The light beam formed by the light engine can carry various information, such as color information, image information, brightness information, etc. The embodiments are not limited to the type and number of light engines, which can be any of a DLP light engine, a Micro-LED light engine, and an LCOS light engine, and can be set according to actual use requirements.

[0037] Referring now to the drawings Figure 1 and Figure 3In an embodiment provided by the present application, the optical waveguide module 100 comprises a waveguide body 10, a light folding member 20, a light transmission and homogenization member 30, and a light absorption layer 40. The waveguide body 10 has a first surface 101, a second surface 102, and a side wall surface 103. The first surface 101 and the second surface 102 are opposite to each other, and the side wall surface 103 is connected between the first surface 101 and the second surface 102. The waveguide body 10 is provided with a coupling-in region 11, a mounting region 13, and a coupling-out region 12. The coupling-in region 11 is arranged on the first surface 101. After a light beam is coupled into the waveguide body 10 through the coupling-in region 11, part of the light rays are coupled out of the waveguide body 10 through the coupling-out region 12 in a specified transmission direction X to form image light, and part of the light rays propagate to the mounting region 13 to form stray light. The mounting region 13 is arranged on the second surface 102 and corresponds to the coupling-in region 11. The light folding member 20 is arranged on the mounting region 13. The light folding member 20 is used to deviate part of the light beam from the specified transmission direction X and transmit the light beam toward the side wall surface 103. The light transmission and homogenization member 30 is arranged on the side wall surface 103. The light transmission and homogenization member 30 has a diffusion part 31 for diffusing stray light. The light absorption layer 40 is arranged on a side of the light transmission and homogenization member 30 away from the side wall surface 103. The diffusion part 31 is arranged between the light absorption layer 40 and the side wall surface 103.

[0038] When the light beam is coupled into the waveguide body 10 through the coupling-in region 11 in the specified propagation direction, since the waveguide body 10 can couple in light beams of specific diffraction orders, most of the light beams can be coupled into the waveguide body 10 through the coupling-in region 11 and transmitted to the coupling-out region 12 to form pattern light. A small part of the light beams directly penetrates through the waveguide body 10 to the second surface 102 and forms stray light on the second surface 102 when coupled into the waveguide body 10 through the coupling-in region 11 or during the propagation process in the waveguide body 10.

[0039] Since the stray light can affect the display effect of the display area, by arranging the light folding member 20 on the mounting region 13, the stray light propagating to the mounting region 13 can be transmitted to the side wall surface 103, thereby effectively reducing the interference of the stray light on the display area and improving the display effect and use safety. In addition, the light transmission and homogenization member 30 is arranged on the side wall surface 103 and is used for light transmission to realize homogenization of the light beam transmitted to the side wall surface 103, which can improve the uniformity of the light beam distribution on the side wall surface 103, avoid local concentration of stray light, and cause heat to concentrate in a single position, thereby facilitating heat dispersion, improving heat dissipation efficiency, and reducing the overall temperature. Further, the light homogenization member 30 has the diffusion part 31. After the stray light is homogenized on the side wall surface 103, the stray light can be conducted into the diffusion part 31 for diffusion, which can further improve the uniformity of the light beam distribution and additionally increase the heat distribution area of the light beam, so that the overall temperature is further reduced. At the same time, the optical waveguide module 100 further comprises the light absorption layer 40. The light absorption layer 40 can absorb the stray light diffused through the diffusion part 31, prevent the stray light from leaking from the side of the diffusion part 31, and further reduce the interference on the environment.

[0040] Next, each component of the optical waveguide module 100 and the specific structure of each component will be introduced one by one.

[0041] Please refer to Figure 1 , the outline of the waveguide body 10 is generally in the form of a flat plate, which is used to guide and transmit a specific diffraction order of light beams. Specifically, the waveguide body 10 can have a first surface 101 and a second surface 102 which are opposite to each other, so that the light beams entering the inside of the waveguide body 10 are confined between the first surface 101 and the second surface 102 and propagate between the first surface 101 and the second surface 102 by total internal reflection or diffraction. The waveguide body 10 can specifically be a flat plate made of at least any one of glass, optical plastic, resin, silicon or other high refractive index optical transmission materials. The shape and thickness of the waveguide body 10 in the present embodiment are not limited and can be set according to actual use requirements to provide good optical properties, for example, it can be rectangular, circular or other shapes. It should be noted that in other embodiments, the waveguide body 10 can also be an optical plate with a certain curvature, for example, the surface of the waveguide body 10 can be a free-form surface or an aspheric surface, and the distance between the first surface 101 and the second surface 102 defines the thickness of the optical plate.

[0042] In the present embodiment, the surface of the waveguide body 10 is further provided with a coupling-in region 11, a mounting region 13 and a coupling-out region 12. The coupling-in region 11 and the coupling-out region 12 are spaced apart, the coupling-in region 11 is used for coupling-in light beams, and the coupling-out region 12 is used for coupling-out light beams. The mounting region 13 is opposite to the coupling-in region 11, and the mounting region 13 is used for mounting the light turning member 20 to deviate stray light from the display area, i.e., the area where the surface of the waveguide body 10 is located. The present embodiment does not limit the specific positions of the coupling-in region 11 and the coupling-out region 12 on the waveguide body 10, for example, the coupling-in region 11 and the coupling-out region 12 can be provided on the same surface of the waveguide body 10, or can be provided on different surfaces of the waveguide body 10, and can be set according to actual practical requirements. It should be noted that the coupling-out region 12 is always located on the surface of the waveguide body 10 facing the user, and the mounting region 13 and the coupling-in region 11 are respectively located on two opposite surfaces of the waveguide body 10. As a specific example, in the present embodiment, the coupling-in region 11 and the coupling-out region 12 are spaced apart and are both provided on the first surface 101, and the mounting region 13 is provided on the second surface 102.

[0043] Please refer to Figure 1 and Figure 2The coupling-in region 11 is configured to couple the light beam formed by the light source into the waveguide body 10 and make the light beam satisfy the condition of total reflection propagation in the waveguide body 10. The coupling-in region 11 can be provided with an optical structure, such as one of a diffraction element, for example, a grating, a prism, a photonic crystal, etc., to ensure that the light beam can enter the waveguide body 10 according to the expected light path. The specific structure of the coupling-in region 11 is not limited in the embodiment, and the coupling-in region 11 can include a grating, such as a straight grating, an inclined tooth grating, a blazed grating, a surface relief grating, a volume holographic grating, etc., which can be set according to actual use requirements. When the light beam propagates to the coupling-in region 11 along the specified direction, most of the light beam can be coupled into the waveguide body 10 through the coupling-in region 11. Due to the periodic structure or stripe, ruled structure of the optical structure (such as the grating) in the coupling-in region 11, the propagation angle of the light beam changes at the optical structure, and the changed part of the light beam satisfies the condition of total internal reflection and can be coupled out of the waveguide body 10 through the coupling-out region 12 to form an image light. Part of the light beam penetrates the waveguide body 10 and propagates to the mounting region 13 to form stray light. The “specified direction” can be understood as the direction of the light source 210 pointing to the coupling-in region 11, and in the embodiment, the specified direction is substantially perpendicular to the first surface 101 / second surface 102. The “specified transmission direction X” can be understood as the direction of the coupling-in region 11 pointing to the coupling-out region 12.

[0044] The coupling-out region 12 is configured to couple the light beam propagating in the waveguide body 10 according to the specified transmission direction X out of the waveguide body 10 and make the light beam enter the human eye to form virtual information for the user to view. Similarly, the coupling-out region 12 is provided with a plurality of optical structures, which can be a mirror array, a grating, etc., and the embodiment is not limited thereto. As an example, the coupling-out region 12 can include a grating, which can be a one-dimensional grating or a two-dimensional grating, and the embodiment is not limited thereto.

[0045] In the embodiment, the waveguide body 10 further has a side wall surface 103 connected between the first surface 101 and the second surface 102. It should be noted that the side wall surface 103 is arranged close to the coupling-in region 11, that is, when the number of side wall surfaces 103 is one and the waveguide body 10 is substantially rectangular, one side wall surface 103 forms one side of the waveguide body 10 close to the coupling-in region. In some embodiments, the number of side wall surfaces 103 is multiple, and the multiple side wall surfaces 103 are connected end to end to surround the outer peripheral wall surface of the waveguide body 10, each side wall surface 103 is connected between the first surface 101 and the second surface 102, and the multiple side wall surfaces 103, the first surface 101, and the second surface 102 jointly form the profile surface of the waveguide body 10.

[0046] Since part of the light beams of the specific diffraction order propagating along the specified direction can be coupled into the waveguide body 10 along the specified propagation direction and propagate along the specified transmission direction X to form image light when the light beams propagate to the coupling-in region 11, part of the light beams can penetrate the second surface 102 of the waveguide body 10 along the specified propagation direction and form stray light on the second surface 102. In order to improve the visual experience of the user, in the embodiment, the light turning member 20 is arranged on the second surface 102 to conduct the stray light to the side wall surface 103, so as to reduce the interference of the stray light on the display area and improve the display effect and use safety.

[0047] Specifically, the light turning member 20 is arranged on the mounting region 13, and the mounting region 13 is arranged on the second surface 102 and corresponds to the coupling-in region 11. The "corresponds to" can be understood as that the mounting region 13 and the coupling-in region 11 are opposite in space, and the projections of the mounting region 13 and the coupling-in region 11 at least partially overlap when projected along the first surface 101 or the second surface 102. Thus, when projected along the direction perpendicular to the first surface 101, the projection profile of the light turning member 20 and the projection profile of the coupling-in region 11 at least partially overlap, so that the stray light can propagate to the light turning member 20. The light turning member 20 is used to deflect the stray light away from the specified direction and conduct the stray light to the side wall surface 103. The specific type of the light turning member 20 is not limited in the embodiment, which can be an optical device capable of reflecting or refracting light, such as a reflector, a photorefractive crystal, a grating, etc. As a specific example, the light turning member 20 can be a reflector, such as a prism. The stray light is reflected or refracted when contacting the surface of the prism to deviate from the display area (the display area is the extended area of the first surface 101 or the second surface 102), so as to improve the visual effect of the user. In some embodiments, the refractive index of the prism can be equal to the refractive index of the waveguide body 10, which can avoid the heat accumulation on the second surface 102 caused by the excessive loss of the stray light at the prism, and can reduce the probability of the stray light being deflected to other areas, so as to ensure that the stray light can be conducted to the side wall surface 103 as much as possible, improve the deflection efficiency of the light turning member 20, and make the deflection effect.

[0048] As another specific example, the light turning member 20 can be a grating. The stray light is deflected when contacting the optical structure of the grating surface, and propagates to the side wall surface 103, so as to avoid forming stray light in the display area and improve the visual experience of the user. The specific type of the grating is not limited in the embodiment, which can be an inclined grating, and can also be a blazed grating or other grating with optical structure inclined to the grating optical axis.

[0049] When the light folding member 20 is a grating, in order to ensure that the light folding member 20 has good folding efficiency and folding effect on stray light, the parameters of the grating can be adjusted to make the energy of the stray light concentrate on the angle of folding to the side wall surface 103. Specifically, the angle of the grating inclination angle on the light folding member 20 can be greater than or equal to 0° and less than or equal to 60°, and the space occupation ratio of the grating can be greater than or equal to 0.2 and less than or equal to 0.8, so that the diffraction energy of the stray light concentrates on the non-zero reflection order, that is, the energy of the stray light concentrates on the angle that can be deflected to the side wall surface 103, so that most of the stray light propagating to the light folding member 20 can be deflected to the side wall surface 103, effectively reducing the risk of the stray light directly penetrating the light folding member 20 along the specified direction, and improving the folding efficiency and folding effect of the light folding member 20.

[0050] Referring to Figure 2 to Figure 4 In some embodiments, in order to further reduce the heat of the optical waveguide module 100, the optical waveguide module 100 can include a light-transmitting light-uniformizing member 30 and a light-absorbing layer 40. The light-transmitting light-uniformizing member 30 is arranged on the side wall surface 103, and the light-absorbing layer 40 is arranged on the side of the light-transmitting light-uniformizing member 30 away from the side wall surface 103, so that the stray light conducted to the side wall surface 103 can transmit through the light-transmitting light-uniformizing member 30, be uniformized at the light-transmitting light-uniformizing member 30, and form light rays with relatively uniform distribution. On the one hand, it can avoid the local concentration of light beams and cause the heat to concentrate in a single position, which is beneficial to realize the dispersion of heat, improve the heat dissipation efficiency and reduce the overall temperature. On the other hand, it can provide a low-heat environment for the light-absorbing layer 40, which is beneficial to improve the light absorption efficiency of the light-absorbing layer 40.

[0051] In some embodiments, the side wall surface 103 has an extension direction, and the light-transmitting light-uniformizing member 30 is connected to the side wall surface 103 and extends along the extension direction of the side wall surface 103 to form a larger light-uniformizing area. After being deflected by the light folding member 20, the stray light can enter the light-transmitting light-uniformizing member 30 and propagate in the light-transmitting light-uniformizing member 30, so that the heat of the stray light can be distributed in any position of the light-transmitting light-uniformizing member 30, and a relatively uniform temperature distribution environment can be formed, which is beneficial to the absorption of the stray light by the light-absorbing layer 40. The light-transmitting light-uniformizing member 30 is configured to have a certain height and a certain thickness to ensure the light-uniformizing effect. The specific height, specific thickness and material of the light-transmitting light-uniformizing member 30 are not limited in the present embodiment. For example, the light-transmitting light-uniformizing member 30 can be optical plastic or light-uniformizing glass, etc., which are not limited in the present embodiment.

[0052] Referring to Figure 1 , Figure 4 and Figure 5In the embodiment, to further reduce the heat of the optical waveguide module 100, the light-transmitting light uniformizing member 30 has a diffusion portion 31 for diffusing stray light, the diffusion portion 31 is arranged between the light-absorbing layer 40 and the side wall surface 103, and the diffusion portion 31 is capable of transmitting light so that light can be transmitted to the light-absorbing layer 40. Specifically, the diffusion portion 31 is arranged inside the light-transmitting light uniformizing member 30, and when stray light is transmitted to the diffusion portion 31, multiple reflections or refractions occur to form uniform light, thereby avoiding the heat of stray light from being concentrated on a single position. The embodiment does not limit the specific structure of the diffusion portion 31. For example, the diffusion portion 31 can be a cavity 315 for light uniformization, wherein the wall surface of the cavity 315 is capable of reflecting or refracting light beams; the diffusion portion 31 can also be a light-uniformizing solid structure embedded in the cavity 315 and doped with scattering particles; or the diffusion portion 31 can also be a transmissive-reflection layer.

[0053] As a specific example, the diffusion portion 31 is a cavity 315 formed based on the light-transmitting light uniformizing member 30, and a reflection structure 311 is arranged on the wall surface of the cavity 315, so that stray light deflected to the side wall surface 103 is transmitted into the cavity 315 after passing through the light-transmitting light uniformizing member 30, and multiple reflections or refractions occur at the reflection structure 311 to attenuate the energy of the light beam. It should be noted that the cavity 315 can be separately formed inside the light-transmitting light uniformizing member 30, for example, directly hollowed inside, or can be a space defined by the light-transmitting light uniformizing member 315 being spaced apart from other components in space. The embodiment does not limit the specific position of the cavity 315 in the light-transmitting light uniformizing member 30. For example, the cavity 315 can be arranged inside the light-transmitting light uniformizing member 30, that is, the cavity 315 is spaced apart from the side wall surface 103; or the cavity 315 can be recessed from the surface of the light-transmitting light uniformizing member 30 to be covered by the side wall surface 103, that is, the stray light directly enters the cavity 315 through the side wall surface 103, and then is transmitted to the solid inside the light-transmitting light uniformizing member 30.

[0054] As a specific example, the cavity 315 can be spaced apart from the side wall surface 103, that is, the light-transmitting light uniformizing member 30 is at least partially structured to form the cavity 315 spaced apart from the side wall surface 103, the light-absorbing layer 40 is arranged on the side of the light-transmitting light uniformizing member 30 away from the side wall surface 31, and the diffusion portion 31 is arranged between the light-absorbing layer 40 and the side wall surface 103. The light-transmitting light uniformizing member 30 can include a first side portion 301 and a second side portion 302, and the cavity 315 is arranged between the first side portion 301 and the second side portion 302 to space apart the first side portion 301 and the second side portion 302. The first side portion 301 can be arranged to be attached to the side wall surface 103, the light-absorbing layer 40 can be arranged on the surface of the second side portion 302 away from the cavity 315, and the reflection structure 311 can be arranged on the wall surface of the cavity 315, that is, the reflection structure 311 is arranged on the first side portion 301 and the second side portion 302, so that when the stray light propagates into the cavity 315, at least part of the stray light is reflected multiple times by the wall surface of the cavity 315 and then propagates to the light-absorbing layer 40.

[0055] The reflective structure 311 can specifically include a first reflective microstructure 3111 and a second reflective microstructure 3112. The first reflective microstructure 3111 can be arranged on the side of the first side portion 301 facing the cavity 315, and the second reflective microstructure 3112 can be arranged on the side of the second side portion 302 facing the cavity 315. The present embodiment does not limit the specific type of the first reflective microstructure 3111. For example, the first reflective microstructure 3111 can include a micro-lens array. A plurality of micro-lens arrays 3113 arranged on the surface of the first side portion 301 facing the cavity 315 can facilitate improving the reflection efficiency. The first reflective structure 3111 can also include a reflective coating sprayed on the surface of the first side portion 301. It should be noted that the first reflective structure 311 can be transparent to light so that stray light can be transmitted to the light-absorbing layer 40 through the cavity 315. For example, the reflective coating can be specifically a semi-transparent or frosted transparent layer. Alternatively, in some embodiments, the first reflective structure 3111 is partially arranged on the first side portion 301. For example, the adjacent micro-lens arrays 3113 are arranged on the first side portion 301 with a spacing therebetween or the reflective coating is dot-sprayed on different regions of the first side portion 301, so that the light beam can be transmitted to the light-absorbing layer 40 from the gap between the adjacent micro-lens arrays 3113 or the gap between the adjacent reflective coatings.

[0056] Similarly, the second reflective microstructure 3112 can include the above-mentioned micro-lens array and reflective coating. The present embodiment does not limit the arrangement manner of the second reflective microstructure 3112 on the second side portion 302.

[0057] In some embodiments, the first reflective microstructure 3111 can be configured to have a relatively high reflectivity, and the second reflective microstructure 3112 can be configured to have a relatively low reflectivity, which can improve the uniformity of the light beam distribution, effectively reduce the heat concentration phenomenon of the light beam at a single position, and improve the light absorption efficiency of the light-absorbing layer 40. Specifically, the reflectivity of the first microstructure 3111 is greater than that of the second microstructure 3112. Since the first side portion 301 is adjacent to the side wall surface 103, the stray light entering the light-transmitting and light-uniformizing member 30 through the side wall surface 103 can form multiple reflections at the first microstructure 3111 with a relatively high reflectivity, thereby increasing the reflection times of the same light beam and avoiding heat concentration at a single position. When the surface of the second side portion 302 away from the cavity 315 is used to connect the light-absorbing layer 40, the second microstructure 3112 arranged on the second side portion 302 has a low reflectivity, which can facilitate the light beam to exit onto the light-absorbing layer 40 and improve the light absorption efficiency of the light-absorbing layer 40.

[0058] Please refer again to Figure 1 , Figure 3 and Figure 4In the embodiment, the first side 301 is further provided with a light guide portion 32 for receiving the stray light propagated by the light turning member 20 and conducting the stray light into the cavity 315, the light guide portion 32 is not provided with the first reflection microstructure 311 for the stray light to enter into the cavity 315. Specifically, the side wall surface 103 is connected between the coupling-in region 11 and the light turning member, the coupling-out region 13 is arranged at one side of the coupling-in region 11 along the positive direction of the specified transmission direction X, the light guide portion 32 is arranged at one side of the coupling-out region 13 along the negative direction of the specified transmission direction X, and the light guide portion 32 and the side wall surface 103 are arranged side by side. The light guide portion 32 can be a through hole, the through hole is communicated with the cavity 315, and the first reflection structure 311 can surround the outer periphery of the through hole. In some embodiments, the light guide portion 32 can also be a light guide column or a light guide plate (not shown in the figure) with high transmittance, and the embodiment is not specifically limited in this regard.

[0059] Referring to Figure 5 As another specific example, the cavity 315 is recessed from the side of the light transmission and homogenization member 30 connected to the side wall surface 103 opposite to the side wall surface 103, so that the side wall surface 103 covers the cavity 315. That is, the light transmission and homogenization member 30 is arranged spaced apart from the side wall surface 103, and the cavity 315 is arranged between the light transmission and homogenization member 30 and the side wall surface 103. The side of the light transmission and homogenization member 30 facing the cavity 315 is provided with the reflection structure 311, so that the stray light can be directly conducted from the side wall surface 103 into the cavity 315 and diffused at the reflection structure 311, and the diffused light is then sequentially conducted to the solid portion 303 of the light transmission and homogenization member 30 and the light absorption layer 40 through the cavity 315. Specifically, the light transmission and homogenization member 30 includes the solid portion 303, the cavity 315 is arranged between the solid portion 303 and the side wall surface 103, the side wall surface 103 is connected to the light transmission and homogenization member 30 and covers the cavity 315, and the light absorption layer 40 is arranged at the side of the light transmission and homogenization member 30 away from the cavity 315.

[0060] Referring to Figure 6As another specific example, the diffusion portion 31 can be a first light-transmitting and reflecting layer 3113 and a second light-transmitting and reflecting layer 3114 arranged at a distance from each other, and the first light-transmitting and reflecting layer 3113 and the second light-transmitting and reflecting layer 3114 are arranged in a laminated manner between the light-absorbing layer 40 and the side wall surface 103. The first light-transmitting and reflecting layer 3113 and the second light-transmitting and reflecting layer 3114 are used for reflecting and transmitting light, and can be optical film layers provided with reflecting structures 311. As a specific example, the surfaces of the first light-transmitting and reflecting layer 3113 and the second light-transmitting and reflecting layer 3114 facing each other are provided with reflecting structures 311, so that the stray light can be reflected multiple times between the first light-transmitting and reflecting layer 3113 and the second light-transmitting and reflecting layer 3114 and can be conducted to the light-absorbing layer 40. The specific type of the reflecting structures 311 is not limited in the present embodiment, and can be, for example, a microlens array or a convex structure or a groove, etc. It should be noted that the refractive index of the first light-transmitting and reflecting layer 3113 is equal to the refractive index of the second light-transmitting and reflecting layer 3114 to reduce the heat accumulation caused by the multiple loss of the light beam. In addition, the uniformity of the light beam propagation can be ensured, and the overall performance of the optical waveguide module 100 is improved.

[0061] Please refer to Figure 1 and Figure 7 As another specific example, the diffusion portion 31 can also be a light-uniformity solid structure 314 arranged inside the cavity. For example, the light-uniformity solid structure 314 can be optical plastic, optical resin, optical glue, etc. doped with scattering particles, and the specific structure of the scattering particles is not limited in the present embodiment. After the stray light enters the light-transmitting and uniformity member 30, it is conducted to the light-uniformity solid structure 314 and diffused at the scattering particles, so that relatively uniform light is formed, and the heat can be avoided from being concentrated at the same position.

[0062] Please refer to Figure 8 and Figure 9In some embodiments, in order to further improve the diffusion efficiency and diffusion effect of the light-transmitting and light-uniformizing member 30, the light-transmitting and light-uniformizing member 30 can be arranged around the outer periphery of the waveguide body 10 so that the diffusion portion 31 is arranged around. Specifically, the number of the above-mentioned side wall surfaces 103 can be multiple, and the multiple side wall surfaces 103 are sequentially connected end to end to form the outer peripheral wall surface of the waveguide body 10. The light-transmitting and light-uniformizing member 30 is arranged around the outer periphery of the waveguide body 10, so that the diffusion portion 31 is arranged around the multiple side wall surfaces 103, forming a larger diffusion and light-uniformizing area. More specifically, the diffusion portion 31 can include a first sub-diffusion portion 312 and a second sub-diffusion portion 313 which are in communication with each other, the first sub-diffusion portion 312 is adjacent to the coupling-in region 11, the first sub-diffusion portion 312 is arranged between the first side portion 301 and the second side portion 302, and the second sub-diffusion portion 313 is arranged around the periphery of the waveguide body 10, so that the stray light can enter the light-transmitting and light-uniformizing member 30 via the side wall surface 103, and after being reflected or refracted in the first sub-diffusion portion 312, part of the light rays are transmitted into the light-absorbing layer 40, and the other part of the light rays enter the second sub-diffusion portion 313 via the first sub-diffusion portion 312, and are reflected or refracted in the second sub-diffusion portion 313 to form a uniform light beam, and further avoid the heat from being concentrated in a single position.

[0063] In the present embodiment, the light-absorbing layer 40 is arranged on the outer surface of the light-transmitting and light-uniformizing member 30, and the light-absorbing layer 40 is used to absorb the stray light after being uniformly lighted by the light-transmitting and light-uniformizing member 30, and reduce the interference of the stray light on the environment. The light-absorbing layer 40 can specifically include an ink layer 41, the thickness of the ink layer 41 is greater than or equal to 1 mm and less than or equal to 3 mm, for example, the thickness of the light-absorbing layer 40 can be 1 mm or 2 mm. The light-absorbing layer 40 with the thickness has good light-absorbing efficiency and small overall thickness of the light waveguide module 100, which can reduce the overall volume and production cost of the light waveguide module 100. It can be understood that the thickness of the light-absorbing layer 40 can also be other values, which can be set according to actual use requirements.

[0064] In summary, the embodiment of the present application provides a light waveguide module 100, which is provided with a coupling-in area 11, a coupling-out area 12 and a mounting area 13. The mounting area 13 and the coupling-in area 11 are respectively located on the first surface 101 and the second surface 102 of the waveguide body 10 and correspond to each other. The light folding member 20 arranged in the mounting area 13 can transmit the stray light propagating to the mounting area 13 to the side wall surface 103, thereby effectively reducing the interference of the stray light leaking from the front on the display area and improving the display effect and use safety. In addition, the light-transmitting and light-uniformizing member 30 is arranged on the side wall surface 103 and is used for transmitting light to uniformly light the stray light conducted to the side wall surface 103, thereby improving the uniformity of the light beam distribution on the side wall surface 103, avoiding the heat caused by the local concentration of the light beam from being concentrated in a single position, and being beneficial to the dispersion of heat, the improvement of heat dissipation efficiency and the reduction of overall temperature. Further, the light-transmitting and light-uniformizing member 30 has a diffusion part 31, and the stray light can be conducted to the diffusion part 31 for diffusion after being uniformly lighted on the side wall part 103, so as to further improve the uniformity of the light beam distribution and additionally increase the heat distribution area of the light beam, so that the overall temperature is further reduced. Meanwhile, the light waveguide module 100 further comprises an absorbing layer 40, which can absorb the stray light diffused through the diffusion part 31, prevent the stray light from leaking from the side of the diffusion part 31, and further reduce the interference on the environment.

[0065] In the description of the present specification, the description of the terms "one embodiment", "some embodiments", "an example", "a specific example", or "some examples" and the like means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In the present specification, the illustrative description of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any appropriate manner in any one or more embodiments or examples. In addition, the person skilled in the art can combine and combine the different embodiments or examples described in the present specification and the features of the different embodiments or examples without contradiction.

[0066] In addition, the terms "first", "second" are only for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined with "first", "second" can explicitly or implicitly include at least one of the features. In the description of the present application, the meaning of "a plurality of" is at least two, for example, two, three, etc., unless otherwise specifically limited.

[0067] Finally, it should be noted that the above examples are only used to illustrate the technical solutions of the present application, and are not intended to limit the same; although the present application has been described in detail with reference to the foregoing examples, those of ordinary skill in the art will understand that they can still modify the technical solutions described in the foregoing examples, or make equivalent replacements for some of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. An optical waveguide module, characterized by comprising: The application relates to a waveguide body, a light folding member, a light transmission and homogenization member, and a light absorption layer. The waveguide body has a first surface, a second surface and a side wall surface, the first surface and the second surface are opposite to each other, and the side wall surface is connected between the first surface and the second surface. The surface of the waveguide body is provided with a coupling-in area, a mounting area and a coupling-out area, the coupling-in area is arranged on the first surface, part of light rays are coupled out of the waveguide body to form image light through the coupling-out area in a specified transmission direction after the light beams are coupled into the waveguide body through the coupling-in area, and part of the light rays propagate to the mounting area to form stray light; the mounting area is arranged on the second surface and corresponds to the coupling-in area; The light folding member is arranged on the mounting area and is used for conducting the stray light to the side wall surface; The light transmission and homogenization member is arranged on the side wall surface and has a diffusion part for diffusing the stray light; The light absorption layer is arranged on a side of the light transmission and homogenization member away from the side wall surface, and the diffusion part is arranged between the light absorption layer and the side wall surface. When the light folding member is projected in a direction perpendicular to the first surface, the projection contour of the light folding member and the projection contour of the coupling-in area at least partially overlap.

2. The optical waveguide module of claim 1, wherein, The light folding member comprises a prism, and the refractive index of the prism is equal to the refractive index of the waveguide body; or 3. The optical waveguide module of claim 1, wherein, The light folding member comprises a grating, and the grating is an inclined grating or a blazed grating. The diffusion part is a cavity formed based on the light transmission and homogenization member, and at least part of the stray light is propagated to the light absorption layer after being reflected multiple times by the wall surface of the cavity when the stray light propagates into the cavity.

4. The optical waveguide module of claim 1, wherein, The light transmission and homogenization member comprises a first side part and a second side part arranged at intervals, the cavity is arranged between the first side part and the second side part, the first side part is attached to the side wall surface, and the light absorption layer is arranged on a side of the second side part away from the cavity.

5. The optical waveguide module of claim 4, wherein, A first reflection microstructure is arranged on a side of the first side part facing the cavity, a second reflection microstructure is arranged on a side of the second side part facing the cavity, and the reflectivity of the first reflection microstructure is greater than that of the second reflection microstructure.

6. The optical waveguide module of claim 5, wherein, The first reflection microstructure comprises a microlens array and / or a reflective coating; and / or 7. The optical waveguide module of claim 6, wherein the optical waveguide module is configured to be mounted on a printed circuit board. The second reflection microstructure comprises a microlens array and / or a reflective coating. The first side part is provided with a light guide part for receiving the stray light propagated by the light folding member and conducting the stray light into the cavity, and the light guide part is not provided with the first reflection microstructure.

8. The optical waveguide module of claim 6, wherein the optical waveguide module is configured to be mounted on a printed circuit board. The coupling-out area is arranged on a side of the coupling-in area along a positive direction of the specified transmission direction, and the light guide part is arranged on a side of the coupling-out area along a negative direction of the specified transmission direction.

9. The optical waveguide module of claim 8, wherein, The light guide part is a through hole, the through hole communicates with the cavity, and the first reflection microstructure is arranged around the outer periphery of the through hole.

10. The optical waveguide module of claim 8, wherein the optical waveguide module is configured to be mounted on a circuit board. The light transmission and homogenization member is arranged at intervals with the side wall surface, the cavity is arranged between the light transmission and homogenization member and the side wall surface, the light absorption layer is arranged on a side of the light transmission and homogenization member away from the cavity, and a reflection structure is arranged on a side of the light transmission and homogenization member facing the cavity.

11. The optical waveguide module of claim 4, wherein the optical waveguide module is configured to be mounted on a printed circuit board. ​ 12. The optical waveguide module of claim 1, wherein, The diffusion portion comprises a first transmissive-reflection layer and a second transmissive-reflection layer, which are arranged in a laminated manner between the light-absorbing layer and the side wall surface, and the surfaces of the first transmissive-reflection layer and the second transmissive-reflection layer facing each other are provided with reflection structures, and the refractive index of the first transmissive-reflection layer is equal to the refractive index of the second transmissive-reflection layer.

13. The optical waveguide module according to any one of claims 1 to 12, wherein The number of the side wall surfaces is multiple, and the multiple side wall surfaces are connected in a head-to-tail manner to form an outer peripheral wall surface of the waveguide body, and the light-transmitting and light-uniformizing member surrounds the outer periphery of the waveguide body, so that the diffusion portion surrounds the multiple side wall surfaces.

14. The optical waveguide module of any one of claims 1 to 12, wherein, The light-absorbing layer comprises an ink layer, and the thickness of the ink layer is greater than or equal to 1 mm and less than or equal to 3 mm.

15. A display device, characterized by Comprising a light source for forming a light beam; and The light waveguide module according to any one of claims 1 to 14 is located on the light path of the light beam.

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