AR display device

Abstract

An AR display device is provided. The AR display device comprises a device body, a lens, an optical engine system and a processor, the lens, the optical engine system and the processor are arranged in the device body; the lens has a first surface facing away from a human eye, the first surface is provided with a thermal coating, the thermal coating is used for displaying an image; the optical engine system comprises a laser emitter and a light field modulation element, the laser emitter and the light field modulation element are controlled by the processor; the laser emitter is used for emitting laser, the wavelength band of the laser is an invisible light wavelength band; the light field modulation element is used for receiving the laser and reading a hologram loaded by the processor, and modulating the phase of the laser to form at least two image lasers carrying image information; wherein each image laser is focused to a different position of the thermal coating, and the thermal coating displays an image with different brightness according to the energy density of the image laser focused thereto.

Description

Technical Field

[0001] This application relates to the field of AR display technology, and more specifically, to an AR display device. Background Technology

[0002] AR (Augmented Reality) is a technology that merges real-world information with virtual-world information. It not only displays real-world information but also simultaneously shows virtual information, with the two types of information complementing and overlaying each other.

[0003] Most mainstream near-eye augmented reality display devices currently use the principle of optical waveguides. For example, using optical waveguide technology to project images onto the human retina can easily pose a safety risk to the eyes. Some AR display devices also project images onto lenses worn by the user, but when images are projected onto lenses, there are display problems such as low brightness and low contrast. Summary of the Invention

[0004] The purpose of this application is to provide a new technology solution for AR display devices.

[0005] In a first aspect, this application provides an AR display device. The AR display device includes: The device includes a main body, lenses, an optical engine system, and a processor, wherein the lenses, the optical engine system, and the processor are all disposed in the main body of the device. The lens has a first surface facing away from the human eye, and the first surface is provided with a thermal coating, which is used to display images. The optomechanical system includes a laser emitter and an optical field modulation element, both of which are controlled by the processor; The laser emitter is used to emit laser light, and the laser light is in the invisible light band. The optical field modulation element is used to receive the laser and read the hologram loaded by the processor, and modulate the phase of the laser to form at least two image laser beams carrying image information; Each of the image laser beams is focused onto a different position of the thermally sensitive coating, and the thermally sensitive coating displays images of different brightness depending on the energy density of the image laser beam focused onto it.

[0006] Optionally, the optomechanical system further includes a wavelength adjustment element disposed in the transmission optical path of the laser; The wavelength adjustment element is configured to adjust the wavelength of the laser, such that the optical field modulation element modulates the phase of the laser at different wavelengths. The thermal coating displays different colors depending on the received image laser of different wavelengths.

[0007] Optionally, the thermal coating has a temperature threshold, and the AR display device displays a virtual image when the energy density of the image laser focused onto the thermal coating is greater than the temperature threshold.

[0008] Optionally, the optomechanical system further includes an energy adjustment element and a polarization beam splitter element, wherein the energy adjustment element and the polarization beam splitter element are disposed in the transmission optical path of the laser. The energy adjustment element is used to receive the laser emitted by the laser emitter and adjust the polarization direction of the incident laser. The polarization beam splitter is used to receive laser light passing through the energy adjustment element and selectively transmit laser light of a certain polarization state. The optical field modulation element is used to receive laser light passing through the polarization beam splitter.

[0009] Optionally, the energy regulating element is controlled by the processor, and the energy regulating element includes a phase delay element and a driving element. The processor controls the driving element to drive the phase delay element to rotate.

[0010] Optionally, the AR display device further includes an ambient light sensor, which is disposed on the main body of the device; The processor receives information transmitted by the ambient light sensor and controls the energy regulation element based on the information.

[0011] Optionally, the optomechanical system further includes an optical shutter, on which an energy monitoring element is disposed; the optical shutter is disposed between the polarization beam splitter and the optical field modulation element; When the optical shutter is closed, the energy monitoring element monitors the energy density of the laser transmitted to the optical shutter. The optical shutter is controlled by the processor. When the energy density of the laser reaches the threshold set by the energy monitoring element, the processor controls the optical shutter to be in the open state.

[0012] Optionally, the optomechanical system further includes a beam expander and a focusing element, which are disposed in the transmission optical path of the laser. The beam expander is positioned at the front end of the optical field modulation element, and the focusing element is positioned at the rear end of the optical field modulation element.

[0013] Optionally, the light field modulation element includes a liquid crystal molecule array or a microlens array.

[0014] Optionally, the lens has a second surface disposed opposite to the first surface, and an anti-reflective coating is disposed on the second surface.

[0015] Optionally, the main body of the device includes a frame, a sub-shell, and temples, with the sub-shell disposed between the frame and the temples; The sub-shell has two open ends, one of which communicates with the temple and the other open end is connected to the frame. The optomechanical system is housed within the temple and the sub-house.

[0016] According to embodiments of this application, an AR display device is provided. In these embodiments, images are projected onto the lenses of the AR display device, avoiding direct projection onto the retina of the human eye. Simultaneously, a thermally sensitive coating is provided on the side of the lens facing away from the human eye. This coating displays image information of varying brightness according to the energy density of the laser focused on it, thereby improving the image display effect.

[0017] Other features and advantages of this specification will become clear from the following detailed description of exemplary embodiments with reference to the accompanying drawings. Attached Figure Description

[0018] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments of this specification and, together with their description, serve to explain the principles of this specification.

[0019] Figure 1 The diagram shown is a structural schematic of the AR display device provided in an embodiment of this application.

[0020] Figure 2 The diagram shown is a schematic diagram of the connection between the temple and the sub-shell provided in an embodiment of this application.

[0021] Figure 3 The diagram shown is a schematic diagram of the internal structure of the AR display device provided in an embodiment of this application.

[0022] Figure 4 The image shown is a schematic diagram of the lens structure provided in an embodiment of this application.

[0023] Explanation of reference numerals in the attached figures: 1. Main body of the equipment; 10. Frame; 11. Sub-shell; 12. Temple; 2. Lens; 20. Thermal coating; 21. Anti-reflective coating; 3. Optomechanical system; 31. Laser emitter; 32. Energy adjustment element; 33. Polarization beam splitter; 34. Optical shutter; 35. Beam expander; 36. Optical field modulation element; 37. Focusing element; 4. Processor; 5. Ambient light sensor; Detailed Implementation Various exemplary embodiments of this application will now be described in detail with reference to the accompanying drawings. It should be noted that, unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps set forth in these embodiments do not limit the scope of this application.

[0024] The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the scope of this application and its application or use.

[0025] Technologies and equipment known to those skilled in the art may not be discussed in detail, but where appropriate, such technologies and equipment should be considered part of the specification.

[0026] In all the examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values.

[0027] It should be noted that similar labels and letters in the following figures indicate similar items; therefore, once an item is defined in one figure, it does not need to be discussed further in subsequent figures.

[0028] This application provides an AR display device. This AR display device solves the problems of poor display effects, such as low brightness and low contrast, that exist when projecting images onto lenses.

[0029] Reference Figures 1-4 The AR display device includes: a device body 1, a lens 2, an optical engine system 3, and a processor 4, wherein the lens 2, the optical engine system 3, and the processor 4 are all disposed on the device body 1.

[0030] The lens 2 has a first surface facing away from the human eye, and the first surface is provided with a thermal coating 20, which is used to display images.

[0031] The optomechanical system 3 includes a laser emitter 31 and an optical field modulation element 36, both of which are controlled by the processor 4.

[0032] The laser emitter 31 is used to emit laser light, and the laser light is in the invisible light band. The optical field modulation element 36 is used to receive the laser and read the hologram loaded by the processor 4, and modulate the phase of the laser to form at least two image lasers carrying image information. Each of the image laser beams is focused onto a different position of the thermal coating 20, and the thermal coating 20 displays images of different brightness depending on the energy density of the image laser beam focused onto it.

[0033] In this embodiment, the AR display device mainly includes a device body 1, a lens 2, an optical-mechanical system 3, and a processor 4. The lens 2, optical-mechanical system 3, and processor 4 are all integrated into the device body 1, making the AR display device more compact. Specifically, the lens 2 is fixed to the device body 1. When the AR display device is worn, the lens 2 has a first surface facing away from the user's eye, on which a thermally sensitive coating 20 is applied. The AR display device projects an image onto the thermally sensitive coating 20, which then displays the image for the user to view. For example, a coating or spraying process is used to apply the thermally sensitive coating 20 to the first surface of the lens 2. The thermally sensitive coating 20 has a color-changing effect; when an image laser is focused onto the thermally sensitive coating 20, the coating changes color, displaying the image.

[0034] For example, the material of the thermal coating 20 can include: organic reversible thermochromic compounds, such as spirocyclic compounds, bisanthrone compounds, Schiff bases, fluoresceins, triphenylmethane compounds, etc. The material of the thermal coating 20 can also include: inorganic reversible thermochromic pigments, such as iodides, complexes, and double salts of Ag, Cu, and Hg, and compounds formed from cobalt salts, nickel salts, and hexamethylenetetramine.

[0035] The optomechanical system 3 includes a laser emitter 31 and an optical field modulation element 36. Both the laser emitter 31 and the optical field modulation element 36 are controlled by the processor 4. For example, the processor 4 controls the turning on and off of the laser emitter 31 and the optical field modulation element 36.

[0036] The laser emitter 31 serves as the light source element, emitting laser light in the invisible light band. For example, the laser emitted by the laser emitter 31 is invisible to the user throughout the entire optical path transmission process; the user can only see the image ultimately displayed on the thermal coating 20. Because the laser emitted by the laser emitter 31 is invisible light, after being modulated by the light field modulation element 36, the laser becomes an image laser carrying an image phenomenon. This image laser is also invisible to the user during its transmission to the thermal coating 20, preventing the user from directly looking at the laser and protecting the user's eyes. For example, the laser emitter 31 can be an infrared laser.

[0037] The optical field modulation element 36 is disposed in the transmission optical path of the laser. The optical field modulation element 36 can receive the laser emitted by the laser emitter 31 and modulate the phase of the laser. Simultaneously, the optical field modulation element 36 can read the hologram loaded onto it by the processor 4. For example, a driving electrical signal can be applied to the optical field modulation element 36 to modulate the laser phase. The optical field modulation element 36 can also read and recognize image information on the hologram.

[0038] Specifically, processor 4 calculates and generates a hologram from the image to be displayed (target image), and loads the hologram output onto the light field modulation element 36 for display. Simultaneously, processor 4 synchronously controls the laser emitter 31 to emit light. After the light field modulation element 36 is turned on by processor 4, it reads the hologram and modulates the phase of the laser transmitted to it, emitting at least two image laser beams carrying image information. Each image laser beam is focused at a different position on the thermal coating 20, enabling the thermal coating 20 to display the image accordingly.

[0039] For example, the optical field modulation element 36 can process the phase of the incident laser based on the Fourier transform GS algorithm, so that the laser is split into multiple laser beams carrying image information, and each image laser beam carrying image information (where the image information carried by each image laser beam is defined as sub-image information) is focused on a different focal position on the thermal coating 20. The thermal coating 20 displays each sub-image accordingly, and multiple sub-images are presented on the thermal coating 20, forming the target image that can be seen by the user.

[0040] The thermal coating 20 can display images of varying brightness based on the energy density of the image laser focused onto it. For example, when the image laser is focused onto the thermal coating 20, the thermal coating 20 exhibits a color-changing effect; as the energy density of the image laser increases, the brightness of the image displayed on the thermal coating 20 becomes brighter. Therefore, the energy density of the image laser can be adjusted to allow the thermal coating 20 to display images of different brightness, resulting in more realistic brightness and contrast, and improving the display effect of the AR display device.

[0041] Therefore, in this embodiment, a thermal coating 20 is provided on the first surface of the lens 2. The image to be displayed is projected onto the thermal coating 20, and the thermal coating 20 displays the image to be displayed, which is then viewed by the user. The thermal coating 20 can display images of different brightness according to the energy density of the image laser focused onto it, resulting in a better image display effect.

[0042] In one optional embodiment, the energy density of the emitted laser can be adjusted by controlling the output of the laser emitter 31. For example, the laser emitter 31 can be equipped with a speed switch, and the output of the laser emitter 31 can be adjusted by adjusting the speed switch, thereby adjusting the energy density of the emitted laser. Alternatively, in another optional embodiment, a laser energy adjustment component can be provided in the laser's optical path to adjust the laser's energy density.

[0043] It should be noted that processing the image to be displayed using processor 4 to generate a hologram is a technique well-known to those skilled in the art. For example, using 1280p... Taking the 1024 resolution light field modulation element 36 as an example, after the image carrying the transmitted information is input to the processor 4, if the image's aspect ratio is 5:4, it is directly converted to 1280 resolution. A 1024 pixel matrix; if the image dimensions do not meet the requirements, crop or scale it first, then convert it to 1280. A 1024 pixel matrix is ​​then processed to convert the pixel matrix into a grayscale image. Considering that the distance from the focusing element 37 to each pixel region of the thermal coating 20 varies during laser focusing of the image, the grayscale image is decomposed into multiple sub-grayscale images according to different distances. For example, white pixels are limited to display information. Using holographic algorithms, such as the GS algorithm or GSW algorithm based on Fourier transform, the phase of the incident laser can be processed. According to the laser beam focusing position corresponding to each hologram, spherical wave factors with different focal lengths are encoded on the holographic plane of the light field, causing the focus to move on the optical axis. After generating the hologram corresponding to each sub-grayscale image, the multiple holograms are superimposed according to the superposition algorithm to generate a hologram corresponding to the input image, which is then input into the light field modulation element 36. One method of superimposing holograms is to sum the phases of multiple holograms and then take the remainder after dividing by 2π.

[0044] In an optional embodiment, micro-holes are provided on the main body 1 of the device, the micro-holes corresponding to the positions of the optomechanical system 3 and the laser emitter 31, wherein the micro-holes are used for heat dissipation of the AR display device.

[0045] In an optional embodiment, the AR display device is provided with a speaker and has micro-holes on the device body 1 for transmitting sound from the speaker.

[0046] In one embodiment, the optomechanical system 3 further includes a wavelength adjustment element disposed in the transmission optical path of the laser; The wavelength adjustment element is configured to adjust the wavelength of the laser, such that the optical field modulation element 36 modulates the phase of lasers in different wavelength bands. The thermal coating 20 displays different colors according to the received image laser of different wavelengths.

[0047] In this embodiment, the optomechanical system 3 further includes a wavelength adjustment element disposed in the transmission optical path of the laser, which adjusts the wavelength of the laser emitted by the laser emitter 31. For example, the wavelength adjustment element can adjust the laser wavelength to the ultraviolet band, infrared band, and far-infrared band.

[0048] After the wavelength adjustment element adjusts the invisible light wavelength of the laser, the optical field modulation element 36 can perform phase modulation on the laser in different wavelength bands, so that the laser in different wavelength bands can be processed by beam splitting. The laser in different wavelength bands after beam splitting carries image information and is focused onto the thermal coating 20. The thermal coating 20 can display different colors according to the received image laser in different wavelength bands, so that the thermal coating 20 can display a color image.

[0049] For example, when the thermal coating 20 receives an image laser in the ultraviolet band, the thermal coating 20 displays a red image accordingly; when the thermal coating 20 receives an image laser in the infrared band, the thermal coating 20 displays a green image accordingly; when the thermal coating 20 receives an image laser in the far-infrared band, the thermal coating 20 displays a blue image accordingly.

[0050] In the laser optical path, the same wavelength laser is transmitted simultaneously, thus requiring a higher refresh rate for the optical field modulation element 36. That is, the optical field modulation element 36 needs to refresh the hologram at a higher refresh rate.

[0051] In one embodiment, the thermal coating 20 has a temperature threshold. When the energy density of the image laser focused onto the thermal coating 20 is greater than the temperature threshold, the thermal coating 20 changes color, and the AR display device displays a virtual image.

[0052] For example, the material of the thermal coating 20 can be a compound containing organic reversible thermochromic properties, or the material of the thermal coating 20 can also contain inorganic reversible thermochromic pigments. The thermal coating 20 has the effect of changing color when the temperature exceeds a fixed temperature threshold. For example, the color-changing temperature of HgI2 is 137℃, and the color-changing temperature of CuHgI2 is 71℃. Therefore, the temperature threshold of the thermal coating 20 can be defined according to the thermochromic material contained in it.

[0053] When the energy density of the image laser focused onto the thermally sensitive coating 20 is greater than the temperature threshold of the thermally sensitive coating 20, the thermally sensitive coating 20 changes color, correspondingly displaying the image to be displayed, thus allowing the AR display device to show virtual images. When the energy density of the image laser focused onto the thermally sensitive coating 20 is less than the temperature threshold of the thermally sensitive coating 20, the thermally sensitive coating 20 cannot change color, and in this case, the thermally sensitive coating 20 will not display virtual images. Users wearing AR display devices can then view real-world scenes.

[0054] In an optional embodiment, the thermal coating 20 has the effect of changing color when the energy density exceeds a temperature threshold, and the image displayed by the thermal coating 20 becomes brighter as the energy density increases. The higher the energy density of the laser, the higher the temperature focused onto the thermal coating 20.

[0055] Optionally, in order to improve display clarity, when the heat-sensitive coating 20 is deposited on the first surface of the lens 2, there should be a gap between the pixel areas of the heat-sensitive coating 20, that is, when the pixel area changes color, it will not affect the adjacent pixel areas.

[0056] Optionally, after the image laser focuses and leaves the 20-pixel area of ​​the thermal coating, the time delay for the area to change color and return to a transparent state should be less than 0.005s.

[0057] In one embodiment, refer to Figure 3 The optomechanical system 3 further includes an energy adjustment element 32 and a polarization beam splitter 33, which are disposed in the transmission optical path of the laser. The energy adjustment element 32 is used to receive the laser emitted by the laser emitter 31 and adjust the polarization direction of the incident laser. The polarization beam splitter 33 is used to receive the laser light passing through the energy adjustment element 32 and selectively transmit the laser light in one polarization state, so that the polarization direction of the laser light will remain consistent after passing through the polarization beam splitter 33, and the optical field modulation element 36 modulates only the phase of the laser light.

[0058] The optical field modulation element 36 is used to receive laser light passing through the polarization beam splitter 33.

[0059] In this embodiment, the optomechanical system 3 further includes an energy adjustment element 32 and a polarization beam splitter 33, wherein the combination of the energy adjustment element 32 and the polarization beam splitter 33 continuously adjusts the energy density of the emitted laser. The energy adjustment element 32 can rotate the polarization direction of the light, while the polarization beam splitter 33 can select the polarization direction of the transmitted light; the combination of the two enables continuous adjustment of the laser energy. For example, the energy adjustment element 32 and the polarization beam splitter 33 can be combined to continuously adjust the power of the output laser.

[0060] In this embodiment, the optical field modulation element 36 receives the laser light passing through the polarization beam splitter 33. Therefore, the laser light received by the optical field modulation element 36 is a laser light with a polarization state. The optical field modulation element 36 can produce different focusing effects for laser light with different polarization states, so that the laser light with a polarization state is split and focused to different positions of the thermal coating 20.

[0061] In an optional embodiment, the polarization beam splitter 33 is a polarization beam splitter prism. The polarization beam splitter prism consists of two right-angle prisms, and a dielectric film is deposited on the inclined surface where the two right-angle prisms intersect. The laser should be incident on the dielectric film at a 45° angle to ensure that the polarization direction of the outgoing light remains consistent, facilitating the subsequent modulation of the laser beam field by the optical field modulation element 36.

[0062] In one embodiment, the energy regulating element 32 is controlled by the processor 4. The energy regulating element 32 includes a phase delay element and a driving element. The processor 4 controls the driving element to drive the phase delay element to rotate.

[0063] In this embodiment, the energy adjustment element 32 includes a phase delay element and a driving element, wherein the phase delay element can be a half-wave plate. The driving element drives the phase delay element to rotate.

[0064] For example, a half-wave plate creates a half-wave phase difference in the vertical and horizontal polarization directions of the laser. By rotating the half-wave plate, the allowed laser energy density can be controlled, thereby achieving the function of adjusting the display brightness. For example, the higher the allowed laser energy density, the brighter the final image displayed by the thermal coating 20; the lower the allowed laser energy density, the dimmer the final image displayed by the thermal coating 20.

[0065] In one embodiment, refer to Figure 3 The AR display device also includes an ambient light sensor 5, which is disposed on the main body 1 of the device; The processor 4 receives information transmitted by the ambient light sensor 5 and controls the energy regulation element 32 according to the information.

[0066] In this embodiment, an ambient light sensor 5 is provided on the main body 1 of the device. For example, the AR display device is AR glasses, and the ambient light sensor 5 is located above the frame of the AR glasses. The ambient light sensor 5 is used to monitor the intensity of external light when the AR display device is working. Based on the intensity of external light, the brightness of the image displayed by the AR display device can be automatically adjusted.

[0067] Specifically, the ambient light sensor 5 monitors the intensity of external light in real time and transmits the monitored light intensity information to the processor 4. After receiving the information transmitted by the ambient light sensor 5, the processor 4 drives the drive element of the energy adjustment element 32 to move, rotates the phase delay element, and thus changes the polarization state of the laser. In this way, the power of the laser passing through the polarization reflection element changes.

[0068] For example, after the processor 4 receives the information transmitted by the ambient light sensor 5, it needs a laser with a higher energy density to pass through. At this time, the processor 4 drives the driving element to move and rotates the phase delay element so that more of the laser passing through the phase delay element can pass through the polarization beam splitter 33. If, for example, after the processor 4 receives information transmitted by the ambient light sensor 5, it requires a laser with a lower energy density to pass through, the processor 4 drives the driving element to move and rotates the phase delay element, so that the laser passing through the phase delay element can pass through the polarization beam splitter 33 with less energy.

[0069] In one embodiment, refer to Figure 3 The optomechanical system 3 further includes an optical shutter 34, on which an energy monitoring element is disposed; the optical shutter 34 is disposed between the polarization beam splitter 33 and the light field modulation element 36; When the optical shutter 34 is closed, the energy monitoring element monitors the energy density of the laser transmitted to the optical shutter 34; The optical shutter 34 is controlled by the processor 4. When the energy density of the laser reaches the threshold set by the energy monitoring element, the processor 4 controls the optical shutter 34 to be in the open state.

[0070] In this embodiment, the optomechanical system 3 further includes an optical shutter 34, which has an open state and a closed state. The processor 4 controls the opening and closing of the optical shutter 34. When the optical shutter 34 is in the open state, the laser emitted by the laser emitter 31 can continue to be transmitted through the optical shutter 34; when the optical shutter 34 is in the closed state, the laser emitted by the laser emitter 31 cannot pass through the optical shutter 34, and the laser cannot continue to be transmitted. In this case, the user observes the real world.

[0071] Specifically, the optical shutter 34 is controlled by the processor 4 to maintain its open and closed states. An energy monitoring element, such as an energy sensor, is integrated into the optical shutter 34 to monitor the energy density of the incident laser. For example, an optical power meter could be used. When the optical shutter 34 is closed, the energy monitoring element monitors the energy density of the laser emitted from the laser emitter 31 in real time. When the monitored laser energy density is deemed acceptable, the optical shutter 34 opens, and the energy monitoring element is simultaneously adjusted to offset the transmission direction of the laser beam, preventing it from interfering with the normal transmission of the laser.

[0072] For example, the energy density of the laser incident optical shutter 34 is related to the energy adjustment element 32. When the incident laser energy density is too high, it indicates that the laser or the energy adjustment element 32 has malfunctioned. The processor 4 will adjust the optical shutter 34 to the closed state and issue a "beep beep" error message. When the incident laser energy is too low, in addition to considering the problems of the laser and the energy adjustment element 32, it is also necessary to consider whether there is an obstruction in the optical path. At this time, the processor 4 will also adjust the optical shutter 34 to the closed state and issue a "beep beep beep" error message.

[0073] The processor 4 will open the optical shutter 34 only when the monitored laser energy density matches the laser energy density allowed by the energy adjustment element 32 (where the laser energy density allowed by the energy adjustment element 32 is related to the information transmitted from the ambient light sensor 5 to the processor).

[0074] In one embodiment, refer to Figure 3 The optomechanical system 3 further includes a beam expander 35 and a focusing element 37, which are disposed in the transmission optical path of the laser. The beam expander 35 is positioned at the front end of the optical field modulation element 36, and the focusing element 37 is positioned at the rear end of the optical field modulation element 36.

[0075] In this embodiment, the optomechanical system 3 further includes a beam expander 35 and a focusing element 37. The laser emitted from the laser emitter 31 passes sequentially through the beam expander 35, the light field modulation element 36, and the focusing element 37, and is finally focused onto the thermal coating 20 of the lens 2. The laser beam is expanded and then focused, which can improve the quality of the laser light and enhance the image display effect of the AR display device.

[0076] For example, the beam expander 35 in an AR display device adjusts the laser beam spot, thus expanding the beam diameter and reducing the laser divergence angle. The beam expander 35 consists of a negative lens and a positive lens. After passing through the beam expander, the size of the emitted laser beam spot should cover the light field modulation element 36.

[0077] For example, focusing element 37 can be a focusing lens, which can play the role of laser focusing of image.

[0078] In one embodiment, the light field modulation element 36 includes a liquid crystal molecule array or a microlens array.

[0079] In this embodiment, the light field modulation element 36 may be a microlens array or a liquid crystal molecule array, and the light field modulation element 36 is controlled by the processor 4.

[0080] Specifically, the light field modulation element 36, also known as a diffractive optical element, is composed of a liquid crystal molecule array or a microlens array and can modulate the laser light field. Taking liquid crystal molecules as an example, since the phase of the laser is related to the optical path, and when the liquid crystal molecules are deflected under voltage control, their refractive index changes, altering the optical path of the emitted light, thereby achieving the purpose of modulating the phase of the laser. To provide a better user experience, each liquid crystal molecule in the light field modulation element 36 can be considered as a pixel; therefore, the liquid crystal molecule array is at least 1280 pixels. 1024, and the refresh rate should be greater than 60Hz. Since the distances from the focusing element 37 to various points on the lens 2 are not uniform, optical field modulation is required to focus each laser beam to a different position.

[0081] For example, the image to be displayed is converted by processor 4 into a pixel matrix matching the resolution of the light field modulation element 36, and then converted into a grayscale image, where the brightness of each pixel is represented by its grayscale value. The grayscale image is processed using a diffraction optical holography algorithm to generate a hologram that the light field modulation element 36 can recognize. Holographic algorithms such as GS and GSW can be used. The light field modulation element 36 controls the deflection of liquid crystal molecules or microlenses to achieve laser beam splitting. To ensure display quality, the refresh rate of the light field modulation element 36 should be greater than 60Hz.

[0082] It should be noted that the higher the refresh rate of the light field modulation element 36 (a higher refresh rate can bring smoother adaptation and faster response time), the higher the refresh frequency of the hologram by the light field modulation element 36, and the more attention needs to be paid to the heat dissipation of the light field modulation element 36.

[0083] In one embodiment, refer to Figure 4 The lens 2 has a second surface disposed opposite to the first surface, and an anti-reflective coating 21 is disposed on the second surface.

[0084] In this embodiment, an anti-reflection film 21 is provided on the surface of the lens 2 near the human eye. The anti-reflection film 21 can reduce the reflection of light, allow the image laser to be transmitted better, and improve the user's image viewing effect.

[0085] In an optional embodiment, the lens 2 may have a myopia function, which can meet the myopia degree of 200°~800°; it may also have an anti-dispersion function, so that when the laser beam is focused on the surface of the lens 2, it can form a clear pixel when viewed from a 360° angle.

[0086] In one embodiment, refer to Figure 1 and Figure 2 The main body 1 of the device includes a frame 10, a sub-shell 11 and a temple 12, wherein the sub-shell 11 is disposed between the frame 10 and the temple 12; The sub-shell 11 has two open ends, one of which is connected to the temple 12 and the other open end is connected to the frame 10. The optical-mechanical system 3 is housed within the temple 12 and the sub-house 11.

[0087] For example, the opening end where the sub-shell 11 connects to the temple 12 is provided with a first positioning surface and a second positioning surface. The first positioning surface and the second positioning surface are spaced apart. The temple 12 is located between the first positioning surface and the second positioning surface. The outer surface of the temple 12 is bonded and fixed to the first positioning surface and the second positioning surface respectively.

[0088] The optical-mechanical system 3 is housed within the temple 12 and the sub-house 11. For example, the energy adjustment element 32, polarization beam splitter 33, and optical shutter 34 of the optical-mechanical system 3 are located within the temple 12, while the beam expander 35, light field modulation element 36, and focusing element 37 of the optical-mechanical system 3 are located within the sub-house 11. This embodiment demonstrates a reasonable allocation of the placement of the various optical components in the optical-mechanical system 3, improving the user's wearing experience.

[0089] In one specific embodiment, refer to Figure 3 The AR display device includes a lens 2, a processor 4, and an optical-mechanical system 3. A thermal coating 20 is provided on the side of the lens 2 away from the human eye. The various optical components included in the optical-mechanical system 3 are arranged in the transmission optical path of the emitted laser. For example, in the transmission direction of the laser optical path, a laser emitter 31, an energy adjustment element 32, a polarization beam splitter 33, an optical shutter 34, a beam expander 35, a light field modulation element 36, and a focusing element 37 are arranged sequentially.

[0090] Because AR display devices contain many precision components, after the user presses the power button, the entire laser optical path device enters a 3-5 second self-test phase under the control of processor 4. During this self-test, to prevent the optical shutter 34 from accidentally opening due to impacts or other reasons while the device is off, thus causing the laser optical path device to fail the self-test, processor 4 sends a closing command to the optical shutter 34 to ensure it remains closed.

[0091] The processor 4, based on the information (external light intensity reading) transmitted from the ambient light sensor 5, controls the energy adjustment element 32 to ensure the brightness of the image displayed on the AR display device is appropriate. Then, the processor 4 controls the laser emitter 31 to turn on, emitting a laser beam. After passing through the energy adjustment element 32 and the polarization beam splitter 33, the laser beam enters the optical shutter 34. An energy monitoring element on the optical shutter 34 analyzes the laser energy density based on the settings of the energy adjustment element 32. If the laser energy density is reasonable, the processor 4 controls the optical shutter 34 to open; if the laser energy density is unreasonable, the optical shutter 34 remains closed and issues an error message. The light field modulation element 36 is only activated after the optical shutter 34 is open. The laser beam is expanded by the beam expander 35 before entering the light field modulation element 36.

[0092] The light field modulation element 36 reads the hologram loaded onto it from the processor 4 and performs phase modulation on the incident laser, emitting multiple image laser beams carrying image information. The image laser beams pass through the focusing element 37 and are focused onto the thermal coating 20 on the first surface of the lens 2. For example, the thermal coating 20 has a 1280° field of view. A region of 1024 pixels corresponds to a maximum number of modulated beams of 36 light field modulation elements.

[0093] When the heat generated by the image laser focused on the thermal coating 20 exceeds the temperature threshold of the thermal coating 20, the pixel area changes color, displaying a virtual image. The light field modulation element 36 continuously refreshes the hologram, and multiple images displayed on the thermal coating 20 are continuously refreshed accordingly, thus forming a video to be presented to the user. When the heat generated by the image laser focused on the thermal coating 20 does not exceed the temperature threshold of the thermal coating 20, the thermal coating 20 does not change color, displaying the real world.

[0094] In one specific embodiment, when a user uses an AR display device, the AR display device... When the user issues a power-off command, the processor 4 controls the optical shutter 34 to close. The laser emitted from the laser emitter 31 cannot pass through the optical shutter 34 and be received by the light field modulation element 36, thus allowing the user to view the real world while wearing the AR display device. The processor 4 controls the energy adjustment element 32 to reset, and simultaneously controls the light field modulation element 36 and the laser emitter 31 to close. The energy monitoring element integrated into the optical shutter 34 monitors the laser energy. If laser energy is still detected, an error is reported, and the laser emitter 31 is closed again; if no laser energy is detected, the processor 4 shuts down.

[0095] The above embodiments mainly describe the differences between the various embodiments. As long as the different optimization features between the various embodiments are not contradictory, they can be combined to form a better embodiment. For the sake of brevity, they will not be elaborated here.

[0096] While specific embodiments of this application have been described in detail by way of examples, those skilled in the art should understand that the above examples are for illustrative purposes only and are not intended to limit the scope of this application. Those skilled in the art should understand that modifications can be made to the above embodiments without departing from the scope and spirit of this application. The scope of this application is defined by the appended claims.

Claims

1. An AR display device, characterized in that, include: The device body (1), lens (2), optical engine system (3) and processor (4) are all located in the device body (1). The lens (2) has a first surface facing away from the human eye, and the first surface is provided with a thermal coating (20) for displaying images; The optomechanical system (3) includes a laser emitter (31) and an optical field modulation element (36), both of which are controlled by the processor (4). The laser emitter (31) is used to emit laser light, and the laser light is in the invisible light band. The optical field modulation element (36) is used to receive the laser and read the hologram loaded by the processor (4), and modulate the phase of the laser to form at least two image lasers carrying image information; Each of the image laser beams is focused onto a different position of the thermal coating (20), and the thermal coating (20) displays images of different brightness depending on the energy density to which the image laser beam is focused.

2. The AR display device according to claim 1, characterized in that, The optomechanical system (3) further includes a wavelength adjustment element, which is disposed in the transmission optical path of the laser. The wavelength adjustment element is configured to adjust the wavelength of the laser, such that the optical field modulation element (36) modulates the phase of the laser at different wavelengths. The thermal coating (20) displays different colors according to the received image laser of different wavelengths.

3. The AR display device according to claim 1 or 2, characterized in that, The thermal coating (20) has a temperature threshold, and when the energy density of the image laser focused onto the thermal coating (20) is greater than the temperature threshold, the AR display device displays a virtual image.

4. The AR display device according to claim 1, characterized in that, The optomechanical system (3) further includes an energy adjustment element (32) and a polarization beam splitter (33), which are disposed on the transmission optical path of the laser. The energy adjustment element (32) is used to receive the laser emitted by the laser emitter (31) and adjust the polarization direction of the incident laser. The polarization beam splitter (33) is used to receive the laser light passing through the energy adjustment element (32) and selectively transmit the laser light of a polarization state; The optical field modulation element (36) is used to receive laser light passing through the polarization beam splitter (33).

5. The AR display device according to claim 4, characterized in that, The energy regulation element (32) is controlled by the processor (4). The energy regulation element (32) includes a phase delay element and a drive element. The processor (4) controls the drive element to drive the phase delay element to rotate.

6. The AR display device according to claim 5, characterized in that, The AR display device also includes an ambient light sensor (5), which is disposed on the main body (1) of the device; The processor (4) receives information transmitted by the ambient light sensor (5) and controls the energy regulation element (32) according to the information.

7. The AR display device according to claim 4, characterized in that, The optomechanical system (3) further includes an optical shutter (34), on which an energy monitoring element is disposed; the optical shutter (34) is disposed between the polarization beam splitter (33) and the optical field modulation element (36); When the optical shutter (34) is closed, the energy monitoring element monitors the energy density of the laser transmitted to the optical shutter (34); The optical shutter (34) is controlled by the processor (4). When the energy density of the laser reaches the threshold set by the energy monitoring element, the processor (4) controls the optical shutter (34) to be in the open state.

8. The AR display device according to claim 1, characterized in that, The optomechanical system (3) further includes a beam expander (35) and a focusing element (37), which are disposed on the transmission optical path of the laser. The beam expander (35) is positioned at the front end of the optical field modulation element (36), and the focusing element (37) is positioned at the rear end of the optical field modulation element.

9. The AR display device according to claim 1, characterized in that, The light field modulation element (36) includes a liquid crystal molecule array or a microlens array.

10. The AR display device according to claim 1, characterized in that, The lens (2) has a second surface disposed opposite to the first surface, and an anti-reflective coating (21) is disposed on the second surface.

11. The AR display device according to claim 1, characterized in that, The main body (1) of the device includes a frame (10), a sub-shell (11) and a temple (12), wherein the sub-shell (11) is disposed between the frame (10) and the temple (12); The sub-shell (11) has two open ends, one of which is connected to the temple (12) and the other is connected to the frame (10). The optical-mechanical system (3) is placed inside the temple (12) and the sub-house (11).

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