A display device and display apparatus

Abstract

This utility model relates to the field of optical waveguide technology, and provides a display device and display equipment, comprising: a laser emitting component, a focusing component, and an optical waveguide, wherein the optical waveguide includes a coupling-in unit and a coupling-out unit; the laser emitting component is used to emit an image beam to the focusing component; the focusing component is used to focus the image beam and then direct it into the coupling-in unit where total internal reflection occurs, and finally exit through the coupling-out unit. This application focuses the image beam through the focusing component, and the focused beam is completely received by the coupling-in unit, reducing the phenomenon of the image beam energy distribution exceeding the coupling area of ​​the optical waveguide, resulting in high coupling efficiency; furthermore, the focusing component makes the image beam incident on the coupling-in unit more concentrated and directional, thereby forming a more uniform light distribution inside the waveguide, improving the brightness uniformity and display quality of the final exit pupil image.

Description

Technical Field

[0001] This utility model relates to the field of optical waveguide technology, specifically to a display device and display equipment. Background Technology

[0002] With the development of near-eye display technologies such as Augmented Reality (AR) and Mixed Reality (MR), waveguide-based display solutions are gradually becoming mainstream. Waveguide systems guide image light from a microdisplay or scanning source to the human eye through three main stages: coupling in, transmission, and coupling out. This achieves thinner, more transparent display effects, making them suitable for devices such as smart glasses and head-mounted displays.

[0003] Among various light source solutions, laser beam scanning (LBS) light sources are advantageous due to their high brightness and high monochromaticity, which helps improve image quality. However, using LBS light sources in optical waveguide systems still presents a series of technical challenges. Traditional structures typically employ a coupling grating on the optical waveguide to couple the scanning light emitted by the LBS light source into the waveguide, which then propagates to the exit pupil grating to form the image visible to the user. This approach suffers from the following problems: because the LBS scanning spot is relatively large, the coupling grating needs to cover a large area, causing some light rays to fail to fully enter the waveguide at the scanning boundary, resulting in non-uniform light incidence and low initial coupling efficiency; furthermore, due to the non-uniform light incidence, the final image light intensity distribution emanating from the exit pupil grating is uneven, leading to unstable display brightness and affecting sharpness, thus impacting the visual experience. Summary of the Invention

[0004] In view of the shortcomings of existing technologies, such as unstable and unclear brightness, the purpose of this utility model is to provide a display device with stable and clear brightness.

[0005] To solve the above problems, this utility model provides the following technical solution:

[0006] In a first aspect, embodiments of this application provide a display device, including: a laser emitting component, a focusing component, and an optical waveguide, wherein the optical waveguide includes a coupling-in unit and a coupling-out unit;

[0007] The laser emitting component is used to emit an image beam toward the focusing component;

[0008] The focusing component is used to focus the image beam into the coupling unit and cause total internal reflection, and finally emit it through the coupling unit.

[0009] In some embodiments, the surface of the focusing component used to reflect the image beam is a freeform surface or an aspherical surface.

[0010] In some embodiments, the focusing component focuses the image beam into a spot and directs it into the coupling unit.

[0011] In some embodiments, the diameter of the light spot is in the range of 100 μm to 500 μm.

[0012] In some embodiments, the laser emitting component and the focusing component are located on opposite sides of the optical waveguide, and the image beam emitted by the laser emitting component propagates to the focusing component after passing through the optical waveguide.

[0013] In some embodiments, the laser emitting component and the focusing component are arranged symmetrically about the optical waveguide.

[0014] In some embodiments, the focusing component is tilted.

[0015] In some embodiments, the optical waveguide further includes a pupil expanding unit located between the coupling-in unit and the coupling-out unit.

[0016] In some embodiments, the image beam enters the coupling unit and then propagates to the coupling unit via total internal reflection, wherein the step size of the total internal reflection is greater than the length of the coupling unit in the direction of propagation of the image beam within the optical waveguide.

[0017] Secondly, embodiments of this application provide a display device, which includes the display apparatus as described in any of the first aspects.

[0018] The beneficial effects of this invention are: the image beam is focused by the focusing component, and the focused beam is completely received by the coupling unit, reducing the phenomenon that the energy distribution of the image beam exceeds the coupling area of ​​the optical waveguide, resulting in high coupling efficiency; and the focusing component can make the image beam incident on the coupling unit more concentrated and more directional, thereby forming a more uniform light distribution inside the waveguide, improving the brightness uniformity and display quality of the final exit pupil image. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the tilted arrangement of the focusing component and the beam propagation of the present invention.

[0020] Figure 2 This is a schematic diagram showing the symmetrical arrangement of the focusing component and the laser emitting component, as well as the beam propagation of the present invention.

[0021] Figure label:

[0022] 100. Display device; 110. Laser emitting assembly; 120. Focusing assembly; 130. Optical waveguide;

[0023] 131. Coupled-in unit; 132. Coupled-out unit; 133. Waveguide substrate. Detailed Implementation

[0024] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0025] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this utility model, "multiple" means two or more, unless otherwise explicitly specified.

[0026] For ease of description of the first, second, and third directions in the embodiments of this application, the first direction is the left-right direction in the figures, the second direction is the front-back direction in the figures, and the third direction is the up-down direction in the figures. The x-axis arrow direction is referred to as the "right" direction, the y-axis arrow direction as the "up" direction, and the z-axis arrow direction as the "back" direction, but these are not the sole limitations in the actual application of this application.

[0027] like Figure 1 As shown, this embodiment provides a display device, which includes: a laser emitting component 110, a focusing component 120, and an optical waveguide 130. The optical waveguide 130 includes a coupling-in unit 131 and a coupling-out unit 132. The laser emitting component 110 is used to emit an image beam to the focusing component 120. The focusing component 120 is used to focus the image beam and then send it into the coupling-in unit 131 for total internal reflection, and finally emit it through the coupling-out unit 132.

[0028] The image beam is focused by the focusing component, and the focused beam is completely received by the coupling unit, reducing the phenomenon that the energy distribution of the image beam exceeds the coupling area of ​​the optical waveguide, resulting in high coupling efficiency. Furthermore, the focusing component makes the image beam incident on the coupling unit more concentrated and more directional, thereby forming a more uniform light distribution inside the waveguide and improving the brightness uniformity and display quality of the final exit pupil image.

[0029] Optionally, the laser emitting assembly 110 is an LBS light source.

[0030] The LBS light source consists of a laser array containing multiple colors (red / green / blue) or a monochromatic laser source, as well as a drive control circuit and a MEMS scanning mirror, which can output an image beam formed by point-by-point scanning.

[0031] like Figure 1 As shown, optionally, the surface of the focusing component 120 used to reflect the image beam is a freeform surface or an aspherical surface. Freeform or aspherical surfaces have good focusing effects, effectively focusing the original laser spot emitted by the laser emitting component to a size smaller than the original size, and as the incident spot shrinks, the uniformity of light and coupling efficiency also improve.

[0032] The focusing component 120 may be made of high-refractive-index optical glass (such as N-BK7), but this is only an example and should not be construed as a restriction on the selection of the focusing component 120.

[0033] Furthermore, the focusing component 120 focuses the image beam into a spot and directs it into the coupling unit 131.

[0034] Preferably, the diameter of the light spot is in the range of 100 μm to 500 μm. By keeping the diameter of the focused light spot between 100 μm and 500 μm, the area of ​​the coupling unit 131 is reduced, thereby reducing the space occupancy.

[0035] Optionally, the grating area within the coupling unit 131 is between 0.1 and 0.3 mm². The grating area within the coupling unit 131 can be adjusted according to the focusing effect of the focusing unit; this is merely an example and should not be construed as a limitation of this application.

[0036] like Figure 1 As shown, optionally, the optical waveguide 130 also includes a waveguide substrate 133, which has good optical transmittance. This effectively ensures that the light spot coupled into the coupling unit 131 undergoes total internal reflection within the waveguide substrate 133.

[0037] Optionally, the waveguide substrate 133 can be made of either transparent optical glass or high-refractive-index plastic; no specific choice is made here.

[0038] Preferably, the transparent optical glass can be silicon carbide glass.

[0039] Preferably, the high refractive index plastic can be a cyclic olefin copolymer.

[0040] Optionally, the thickness of the waveguide substrate 133 is 0.2~0.7mm.

[0041] Optionally, the laser emitting component 110 and the focusing component 120 are located on opposite sides of the optical waveguide 130, respectively. The image beam emitted by the laser emitting component 110 passes through the optical waveguide 130 and propagates to the focusing component 120. This facilitates the arrangement of the laser emitting component 110 and the focusing component 120, which is beneficial for the miniaturization of the display device 100.

[0042] like Figure 2 As shown, optionally, the laser emitting component 110 and the focusing component 120 are symmetrically arranged about the optical waveguide 130. This symmetrical arrangement facilitates assembly in certain scenarios, thereby reducing the size of the final display device.

[0043] Optionally, the symmetry is configured such that the line connecting the center of the focusing component 120 and the laser emitting component is perpendicular to the surface of the optical waveguide 130.

[0044] like Figure 1 As shown, the focus component 120 can be tilted.

[0045] Optionally, the tilt is configured such that the line connecting the center of the focusing component 120 and the laser emitting component forms an angle with the surface of the optical waveguide 130, so that the position of the image beam after being focused by the focusing component does not coincide with the position where the image beam initially irradiates the optical waveguide substrate.

[0046] Optionally, the optical waveguide 130 also includes a pupil expansion unit, which is located between the coupling unit 131 and the coupling unit 132. By setting the pupil expansion unit, the field of view when the image beam is coupled out can be expanded, thereby increasing the visual experience.

[0047] like Figure 1 or Figure 2 As shown, optionally, after the image beam enters the coupling unit 131, it propagates to the coupling unit via total internal reflection. The step size H of the total internal reflection is greater than the length D of the coupling unit 131 in the propagation direction M of the image beam within the optical waveguide 130. This prevents diffracted light from re-entering the coupling unit and causing secondary diffraction, thus preventing energy loss.

[0048] This solution provides a display device, which includes a display unit 100. The display device includes, but is not limited to, AR devices, MR devices, and near-eye projection terminals.

[0049] Among them, AR devices can be AR smart glasses, such as information prompt glasses, industrial maintenance auxiliary glasses, etc.

[0050] Among them, MR devices can be MR headsets, which can be used for immersive training, remote collaboration, or 3D modeling.

[0051] Among them, near-eye projection terminals can be portable wearable devices used for museum tours, smart exhibitions, and other applications.

[0052] In summary, this utility model provides a display device that focuses an image beam using a focusing component. The focused beam is then fully received by the coupling unit, reducing the phenomenon of the image beam energy distribution exceeding the optical waveguide coupling area and achieving high coupling efficiency. Furthermore, the focusing component makes the image beam incident on the coupling unit more concentrated and more directional, thereby forming a more uniform light distribution inside the waveguide and improving the brightness uniformity and display quality of the final exit pupil image.

[0053] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions 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 this application.

Claims

1. A display device, characterized in that, include: A laser emitting component, a focusing component, and an optical waveguide, wherein the optical waveguide includes a coupling-in unit and a coupling-out unit; The laser emitting component is used to emit an image beam toward the focusing component; The focusing component is used to focus the image beam into the coupling unit and finally out through the coupling unit.

2. The display device according to claim 1, characterized in that: The surface of the focusing component used to reflect the image beam is a freeform surface or an aspherical surface.

3. The display device according to claim 1, characterized in that: The focusing component focuses the image beam into a spot and directs it into the coupling unit.

4. The display device according to claim 3, characterized in that: The diameter of the light spot is in the range of 100 μm to 500 μm.

5. The display device according to claim 1, characterized in that: The laser emitting component and the focusing component are located on opposite sides of the optical waveguide, and the image beam emitted by the laser emitting component propagates to the focusing component after passing through the optical waveguide.

6. The display device according to claim 5, characterized in that: The laser emitting component and the focusing component are arranged symmetrically about the optical waveguide.

7. The display device according to claim 5, characterized in that: The focusing component is tilted.

8. The display device according to claim 1, characterized in that: The optical waveguide also includes a pupil expansion unit, which is located between the coupling-in unit and the coupling-out unit.

9. The display device according to claim 1, characterized in that: The step size of the image beam after entering the coupling unit is greater than the length of the coupling unit in the direction of propagation of the image beam within the optical waveguide.

10. A display device, characterized in that, The display device includes the display apparatus as described in any one of claims 1-9.

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