An AR glasses optical engine module and a method for manufacturing the AR glasses optical engine module.

Abstract

This application provides an AR glasses optical engine module and a method for manufacturing the AR glasses optical engine module, aiming to reduce the size and weight of the AR glasses optical engine module. The AR glasses optical engine module includes an optical waveguide, a driving circuit, and a display chip: a grating structure is formed on one side of the optical waveguide, and the driving circuit is formed on the other side. The grating structure includes an insertion grating and an exit grating. The electrodes of the driving circuit are symmetrically positioned with respect to the insertion grating on both sides of the optical waveguide. The display chip is connected to the electrodes of the driving circuit. When the display chip is driven by the driving circuit, the light emitted by the display chip is coupled into the optical waveguide through the insertion grating and coupled out of the optical waveguide through the exit grating.

Description

Technical Field

[0001] This application relates to the field of optical display device technology, and in particular to an AR glasses optical engine module and a method for manufacturing the AR glasses optical engine module. Background Technology

[0002] Augmented Reality (AR) glasses are wearable products designed to enhance the experience of reality, and can be used in numerous fields such as entertainment, education, and industry. Miniaturization and weight reduction are urgent consumer demands for AR glasses technology innovation. Currently, using micro-light-emitting diodes (Micro LEDs) with waveguide transmission is a feasible solution for achieving thinner and lighter AR glasses.

[0003] However, AR glasses optical engine modules, assembled from various disparate components such as waveguides, Micro LED display chips, driving circuits, and projection lenses, still suffer from problems such as large size and difficulty in achieving full color. The waveguide is used to transmit incident light and direct it to the user's eye. The Micro LED display chip and driving circuit are typically mounted on a Complementary Metal Oxide Semiconductor (CMOS) substrate as an external light engine capable of outputting displayed images. Because there is still a distance between the light engine and the waveguide, the light emitted by the light engine cannot be effectively incident into the waveguide. Therefore, existing AR glasses optical engine modules usually include optical structures such as projection lenses between the waveguide and the light engine to optimize light transmission. This results in the current AR glasses optical engine module being relatively large, affecting the user's wearing experience. Furthermore, different components are manufactured by different companies, and the varying manufacturing processes of these companies can lead to incompatibility and compatibility issues among the components of the AR glasses optical engine module, further increasing the cost of AR glasses. Summary of the Invention

[0004] This application provides an AR glasses optical engine module, aiming to reduce the size and weight of the AR glasses optical engine module and improve the user's wearing comfort.

[0005] In a first aspect, this application provides an AR glasses optical engine module, wherein the AR glasses optical engine module includes an optical waveguide, a driving circuit, and a display chip:

[0006] The optical waveguide has a grating structure on one side and all driving circuits on the other side. The grating structure includes a coupled-in grating and a coupled-out grating. The electrodes of the driving circuit are symmetrical to the coupled-in grating on both sides of the optical waveguide.

[0007] The display chip is connected to the electrodes of the driving circuit. When the display chip is driven by the driving circuit, the light emitted by the display chip is coupled into the optical waveguide through the coupling grating and coupled out of the optical waveguide through the decoupling grating.

[0008] Optionally, the AR glasses optical engine module further includes: a glass substrate;

[0009] The driving circuit is located on the glass substrate and bonded to the side of the optical waveguide that does not have the grating structure.

[0010] Optionally, the grating structure is fabricated on the optical waveguide using a nanoimprinting process.

[0011] Optionally, the driving circuit is fabricated on the side of the optical waveguide without the grating structure using a photolithography process.

[0012] Optionally, the display chip is die-bonded to the electrodes of the driving circuit using wafer bonding technology.

[0013] Optionally, the display chip is a red display chip, or a blue display chip, or a green display chip.

[0014] Secondly, this application also provides a color AR glasses optical engine module, wherein the color AR glasses optical engine module includes a plurality of AR glasses optical engine modules based on the first aspect, wherein the plurality of AR glasses optical engine modules include at least one AR glasses optical engine module configured with a red display chip, at least one AR glasses optical engine module configured with a blue display chip, and at least one AR glasses optical engine module configured with a green display chip.

[0015] Thirdly, this application provides a method for manufacturing an optical engine module for AR glasses, the method comprising:

[0016] At least one grating structure is fabricated on a grating wafer, and each of the at least one grating structure includes a coupled-in grating and a coupled-out grating;

[0017] At least one driving circuit is fabricated on the side of the grating wafer without the grating structure, wherein the electrodes in the at least one driving circuit are symmetrical to the positions of the coupled grating in the at least one grating structure on both sides of the grating wafer;

[0018] A display chip is mounted on the electrode of each of the at least one driving circuit;

[0019] Based on the number of grating structures fabricated on the grating wafer, the grating wafer is cut to obtain at least one AR glasses optical engine module.

[0020] Further, the step of fabricating at least one driving circuit on the side of the grating wafer without the grating structure includes:

[0021] On the side of the grating wafer without the grating structure, at least one driving circuit is fabricated using a photolithography process.

[0022] Alternatively, the at least one driving circuit is fabricated on a glass substrate, and the glass substrate with the at least one driving circuit is bonded to the side of the grating wafer that does not have the grating structure.

[0023] Furthermore, the display chip is a red display chip, or a blue display chip, or a green display chip.

[0024] This application provides an AR glasses optical engine module, which includes an optical waveguide, driving electrodes, and a display chip. A grating structure is formed on one side of the optical waveguide, and a driving circuit is formed on the other side. The electrodes of the driving circuit and the coupling grating of the grating structure are symmetrically positioned on both sides of the optical waveguide. The display chip is connected to the electrodes of the driving circuit, so that when the display chip is driven by the driving circuit, the light emitted by the display chip is coupled into the optical waveguide through the coupling grating and coupled out of the optical waveguide through the coupling grating. In this embodiment, the driving circuit can be fabricated on the optical waveguide, integrating the driving circuit, display chip, and optical waveguide together. This allows the light emitted by the display chip to be directly coupled into the optical waveguide through the coupling grating, eliminating the need to add optical components such as a projection lens between the display chip and the optical waveguide for optical path correction. It also eliminates the need for separate substrates (such as CMOS substrates) for the driving circuit and display chip, thereby reducing the size and weight of the AR glasses optical engine module and improving user comfort. Attached Figure Description

[0025] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0026] Figure 1 This is a schematic diagram of the structure of an AR glasses optical engine module provided in an embodiment of this application.

[0027] Figure 2 This is a schematic diagram illustrating the transmission of light in the optical engine module of AR glasses, as provided in an embodiment of this application.

[0028] Figure 3 This is a schematic diagram showing the positional relationship between a driving circuit and an optical waveguide provided in an embodiment of this application.

[0029] Figure 4 This is a schematic diagram of the structure of another AR glasses optical engine module provided in the embodiments of this application.

[0030] Figure 5 This is a schematic diagram of a process for fabricating a grating structure using nanoimprint lithography provided in an embodiment of this application.

[0031] Figure 6 This is a vertical cross-sectional schematic diagram of a grating structure located on an optical waveguide provided in an embodiment of this application.

[0032] Figure 7 This is a schematic diagram illustrating the process of fabricating a drive circuit using photolithography in an embodiment of this application.

[0033] Figure 8 This is a schematic diagram of the structure of a color AR glasses optical engine module provided in an embodiment of this application.

[0034] Figure 9 This is a flowchart illustrating a method for manufacturing an AR glasses optical engine module as provided in an embodiment of this application.

[0035] Figure 10 This is a schematic diagram illustrating a process of first cutting a grating wafer and then installing a display chip, as provided in an embodiment of this application.

[0036] Figure 11 This is a flowchart illustrating another method for manufacturing an AR glasses optical engine module provided in this application embodiment. Detailed Implementation

[0037] To make the objectives and implementation methods of this application clearer, the exemplary implementation methods of this application will be clearly and completely described below with reference to the accompanying drawings of the exemplary embodiments of this application. Obviously, the exemplary embodiments described are only some embodiments of this application, and not all embodiments.

[0038] It should be noted that the brief descriptions of terms in this application are only for the convenience of understanding the embodiments described below, and are not intended to limit the embodiments of this application. Unless otherwise stated, these terms should be understood in their ordinary and common meaning.

[0039] In this application, the terms "first," "second," "third," etc., used in the specification, claims, and accompanying drawings are used to distinguish similar or related objects or textual entities, and do not necessarily imply a specific order or sequence, unless otherwise specified. It should be understood that such terms are interchangeable where appropriate.

[0040] The terms “comprising” and “having”, and any variations thereof, are intended to cover but not exclude inclusion, for example, a product or device that includes a range of components is not necessarily limited to all of the components that are clearly listed, but may include other components that are not clearly listed or that are inherent to such product or device.

[0041] The term "module" refers to any known or subsequently developed hardware, software, firmware, artificial intelligence, fuzzy logic, or combination of hardware and / or software code that is capable of performing the functions associated with that element.

[0042] Currently, the main display components used in AR glasses include Micro LED display chips, Micro Organic Light Emitting Diode (Micro OLED) display chips, Liquid Crystal on Silicon (LCOS) display chips, Digital Light Processing (DLP) display modules, and Laser Beam Scanning (LBS) display modules. These display components typically need to be assembled with driving circuits, light sources, substrates, etc., to form a light engine that can output displayed images. This light engine, along with the optical module, forms the core component of the AR glasses: the AR glasses optomechanical module. The optical module, depending on the display chip used, can include optical devices such as polarizers, prisms, lenses, and optical waveguides. Combining Micro LED display chips with optical waveguide transmission is one of the main ways to achieve miniaturization and lightweight design of AR glasses. However, in existing solutions that combine Micro LED display chips with optical waveguides, the Micro LED display chips and their required complementary metal-oxide-semiconductor (CMOS) substrates are usually manufactured by different companies and then assembled together as the external optical engine of the AR glasses' optical engine module. The optical waveguides are usually manufactured by another company. Finally, the manufacturer of the AR glasses assembles the optical waveguides with the external optical engine containing the Micro LED display chips to obtain the AR glasses' optical engine module. The inconsistent process levels of different manufacturers lead to an increase in the cost of the final assembled AR glasses' optical engine module. In addition, in order to ensure that the light emitted by the Micro LED display chip can be better incident into the optical waveguide, there are usually optical structural components such as projection lenses between the external optical engine containing the Micro LED display chip and the optical waveguide. This results in the assembled AR glasses' optical engine module still being relatively large, affecting the user's wearing experience.

[0043] Based on this, this application provides an AR glasses optical engine module, aiming to reduce the size and weight of the AR glasses optical engine module. The specific embodiments of the AR glasses optical engine module provided in this disclosure will be described in detail below with reference to the accompanying drawings.

[0044] Figure 1 This is a structural schematic diagram of an AR glasses optical engine module provided in this application. Figure 1 As shown, the AR glasses optical engine module includes an optical waveguide 10, a driving circuit 30, and a display chip 40.

[0045] The optical waveguide 10 has a grating structure 20 on one side and all driving circuits 30 on the other side. The grating structure 20 includes a coupling grating 201 and a coupling grating 202. The electrodes 301 of the driving circuit 30 are symmetrical to the coupling grating 201 on both sides of the optical waveguide 10.

[0046] Optionally, the optical waveguide can be a surface-relief optical waveguide, such as a grating wafer with a grating structure, wherein the grating wafer can be a glass wafer or the other type that directly serves as the optical waveguide medium for light transmission. Alternatively, the optical waveguide can also be a holographic grating waveguide, an arrayed optical waveguide, a coaxial air guide (BirdBath), etc. In this application, a grating wafer with a grating structure, i.e., a surface-relief optical waveguide, will be used as an example for explanation.

[0047] The display chip 40 is connected to the electrode 301 of the driving circuit 30. When the display chip 40 is driven by the driving circuit 30, the light emitted by the display chip 40 is coupled into the optical waveguide 10 through the coupling grating 201 and coupled out of the optical waveguide 10 through the coupling grating 202.

[0048] Optionally, the display chip can be a red display chip, a blue display chip, or a green display chip. Alternatively, the display chip can be a Micro LED display chip, a Micro OLED display chip, etc. This application will take a Micro LED display chip as an example. Figure 2 This is a schematic diagram illustrating the transmission of light within the optical engine module of AR glasses, as provided in an embodiment of this application. Figure 2As shown in the figure, the waveguide 10, coupling grating 201, coupling grating 202, and display chip 40 are included. It should be noted that the driving circuit structure is omitted in the figure to more clearly illustrate the light transmission process in the waveguide. If the display chip is a self-emissive display chip such as a Micro LED or Micro OLED, the light emitted by the chip enters the waveguide, is coupled into the waveguide (e.g., a grating wafer) by the coupling grating for propagation, and is then coupled out by the coupling grating and directed to the target's eye. If the display chip is a non-self-emissive display chip such as an LCOS chip, the light emitted from an external light source passes through the LCOS chip before entering the waveguide. The LCOS chip carries projection image information and corrects the light emitted from the external light source to project a corresponding image. The corrected light is then coupled into the waveguide by the coupling grating for propagation, and is coupled out by the coupling grating and directed to the target's eye.

[0049] The AR glasses optical engine module provided in this application embodiment directly fabricates the driving circuit on the optical waveguide, integrating the driving circuit, display chip, and optical waveguide together. This allows the light emitted by the display chip to be directly coupled into the optical waveguide through the coupling grating, eliminating the need to add optical structures such as projection lenses between the display chip and the optical waveguide for optical path correction. It also eliminates the need for separate substrates (such as CMOS substrates) for the driving circuit and display chip, thereby reducing the size and weight of the AR glasses optical engine module and improving user comfort.

[0050] Furthermore, in order to improve the yield of the grating structure on the optical waveguide, the AR glasses optical engine module also includes: a glass substrate;

[0051] The driving circuit is located on the glass substrate and bonded to the side of the optical waveguide that does not have the grating structure.

[0052] Figure 3 This is a schematic diagram illustrating the positional relationship between a driving circuit and an optical waveguide, provided as an embodiment of this application. Figure 3 As shown, the figure includes an optical waveguide 10, a coupled grating 201, a coupled grating 202, a driving circuit 30, electrodes 301 of the driving circuit, and a glass substrate 50. Figure 3 The image above shows a driving circuit directly fabricated on an optical waveguide, where the electrodes of the driving circuit correspond to the positions of the coupling gratings in the grating structure of the optical waveguide. Figure 3The diagram below illustrates a scenario where the driving circuit is fabricated on a glass substrate, and then the glass substrate with the driving circuit is bonded to the side of the optical waveguide without a grating structure. The electrodes of the driving circuit correspond to the positions of the coupling gratings in the optical waveguide's grating structure. Accordingly, by first fabricating the driving circuit on the glass substrate and then bonding the glass substrate to the side of the optical waveguide without a grating structure, damage to the grating structure on the optical waveguide is avoided when directly fabricating the driving circuit on the grating structure, thus improving the yield of the grating structure on the optical waveguide. Figure 4 This is a schematic diagram of another AR glasses optical engine module provided in an embodiment of this application. Figure 4 As shown, the driving circuit 30 is fabricated on the glass substrate 50, and the glass substrate 50 on which the driving circuit 30 is fabricated is bonded to the side of the optical waveguide 10 without the grating structure. The electrode 301 of the driving circuit corresponds to the position of the coupling grating 201 of the grating structure of the optical waveguide 10.

[0053] Optionally, the grating structure can be fabricated on the optical waveguide using a nanoimprinting process.

[0054] Figure 5 This is a schematic diagram illustrating a process for fabricating a grating structure using nanoimprint lithography, provided as an embodiment of this application. Figure 5 As shown, the grating wafer needs to be cleaned before nanoimprinting to remove various contaminants such as organic matter and metal particles that may be present on the grating wafer. After cleaning, nanoimprinting adhesive is evenly coated onto the surface of the grating wafer using a spin coating process. Then, the nanoimprinting process begins using a grating master on a roller, transferring the grating structure onto the nanoimprinting adhesive on the grating wafer. Simultaneously, the nanoimprinting adhesive on the grating wafer is cured by heating and / or ultraviolet irradiation, i.e., the curing process. Finally, the grating wafer is detached from the grating master to obtain the grating structure on the grating wafer. The grating structure fabricated by nanoimprinting is shown below. Figure 6 As shown, Figure 6 This is a vertical cross-sectional schematic diagram of a grating structure located on an optical waveguide, provided as an embodiment of this application. Figure 6 As shown, the grating structure includes an insertion grating 201 for coupling external light (such as light emitted by a display chip) into the optical waveguide 10, and an extraction grating 202 for coupling light propagating in the optical waveguide 10 out of the optical waveguide 10.

[0055] Furthermore, since different colors of light (such as red light emitted by a red display chip, blue light emitted by a blue display chip, and green light emitted by a green display chip) have different wavelengths, the emission angles of different colors of light at the coupling grating of the same grating structure may differ. Therefore, in some implementations, to further improve the user experience, different grating structures can be fabricated for display chips of different colors. For example, for red display chips, coupling gratings for coupling in red light and coupling gratings for coupling out red light can be fabricated; for blue display chips, coupling gratings for coupling in blue light and coupling gratings for coupling out blue light can be fabricated; and for green display chips, coupling gratings for coupling in green light and coupling gratings for coupling out green light can be fabricated to adapt to the wavelength characteristics of different colors of light.

[0056] Optionally, the driving circuit can be fabricated on the side of the optical waveguide without the grating structure (e.g., the side with the grating structure on the grating wafer) using photolithography. Taking the fabrication of the driving circuit on the grating wafer as an example... Figure 7 This is a schematic diagram illustrating a process for fabricating a drive circuit using photolithography, as provided in an embodiment of this application. Figure 7 As shown, the photolithography process can include the following steps: cleaning, photoresist coating, pre-baking, exposure, development, hardening, etching, and stripping. Cleaning involves using a brush to spray clean impurities from the grating wafer surface, or using solutions such as deionized water or potassium hydroxide to clean and dry it. Photoresist coating involves uniformly applying a layer of photoresist (PR) to the side of the grating wafer without the grating structure. Pre-baking involves baking the PR-coated grating wafer at a certain temperature for a period of time to cure the PR and evaporate the PR-containing solution on the grating wafer. Exposure involves irradiating the back side of the grating wafer (the side without the grating structure) with ultraviolet light (UV light). The PR in the UV-exposed area undergoes photodecomposition or degradation, making it more soluble in the developer. The photoresist under the mask (with the driving circuit pattern) is less soluble in the developer because it has not been exposed to UV light, thus transferring the driving circuit pattern from the mask to the photoresist on the back side of the grating wafer. Developing involves using a developing solution to remove the photoresist (PR) layer from the UV-exposed areas. Hardening involves using high-temperature treatment to make the PR more robust. Etching involves using chemical solvents to remove conductive layers such as indium tin oxide (ITO) semiconductor films and metal plating without PR coverage, thereby fabricating the driving circuitry on the grating wafer. Stripping involves using an alkaline solution to remove any remaining PR from the grating wafer. Finally, three driving circuits for driving the red, blue, and green display chips are fabricated on the back side of the grating wafer.

[0057] Optionally, the display chip is bonded to the electrodes of the driving circuit using wafer bonding technology. The display chip is bonded to the electrodes of the driving circuit on the back side of the grating wafer using wafer bonding technology, and the display chip is connected to the electrodes of the driving circuit, which drives the display chip to emit light. The wafer bonding technology may include direct silicon bonding, anodic bonding, eutectic bonding, adhesive bonding, etc.

[0058] To achieve full-color AR glasses, based on the above embodiments, this application provides a color AR glasses optical engine module, wherein the color AR glasses optical engine module includes multiple AR glasses optical engine modules as described in the above embodiments, and the multiple AR glasses optical engine modules include at least one AR glasses optical engine module configured with a red display chip, at least one AR glasses optical engine module configured with a blue display chip, and at least one AR glasses optical engine module configured with a green display chip. Figure 8 This is a schematic diagram of the structure of a color AR glasses optical engine module provided in an embodiment of this application. Figure 8 As shown, the AR glasses optical engine module corresponding to display chip A, the AR glasses optical engine module corresponding to display chip B, and the AR glasses optical engine module corresponding to display chip C are bonded together to solve the problem of difficulty in achieving full color in AR glasses. Display chips A401, B402, and C403 are respectively one of a red display chip, a green display chip, and a blue display chip. It should be understood that the embodiments of this application do not limit the order of each color display chip in the color AR glasses optical engine module. Figure 8 The order shown is just one example. Additionally, the integrated system driver chip and control chip used to control the optical engine module of the color AR glasses can be externally connected to the optical engine module of the color AR glasses using a flexible printed circuit (FPC) connection to control the colors displayed by the optical engine module.

[0059] Based on the above-mentioned AR glasses optical engine module, this application embodiment also provides a method for manufacturing the AR glasses optical engine module. Figure 9 A flowchart of a method for manufacturing an optical engine module for AR glasses, the method including:

[0060] S901: At least one grating structure is fabricated on a grating wafer, wherein each grating structure in the at least one grating structure includes an input grating and an output grating.

[0061] Among them, grating structures can be fabricated on grating wafers using nanoprinting technology. The fabrication process for grating structures can also include micro-nano processing, electron beam exposure, and ion etching.

[0062] S902: At least one driving circuit is formed on the side of the grating wafer without the grating structure, wherein the electrodes of the at least one driving circuit are symmetrical to the coupling grating of the at least one grating structure on both sides of the grating wafer.

[0063] Among them, the driving circuit can be fabricated on the side of the optical waveguide without a grating structure using photolithography. The process for fabricating the driving circuit can also include acid-resistant printing process, laser engraving process, and other methods.

[0064] S903: A display chip is mounted on an electrode in each of the at least one driving circuit.

[0065] Among these technologies, display chips can be mounted onto the electrodes of the driving circuit using techniques such as wafer bonding and mass transfer. Specifically, wafer bonding technologies can include direct silicon bonding, anodic bonding, eutectic bonding, and adhesive bonding.

[0066] S904: Based on the number of grating structures fabricated on the grating wafer, cut the grating wafer to obtain at least one AR glasses optical engine module.

[0067] Laser cutting of grating wafers can be used to obtain at least one AR glasses optical engine module. Each AR glasses optical engine module can include a grating structure, a driving circuit, and a display chip.

[0068] This application creates an AR glasses optical engine module by fabricating a grating structure on one side of a grating wafer, a driving circuit on the other side, and directly mounting a display chip on the grating wafer. This integrates the driving circuit, the display chip, and the waveguide, allowing light emitted from the display chip to be directly coupled into the waveguide (i.e., the grating wafer) from the grating. This eliminates the need for optical components such as projection lenses between the display chip and the grating wafer to correct the optical path, and also eliminates the need for separate substrates (such as CMOS substrates) for the driving circuit and the display chip. This reduces the size and weight of the AR glasses optical engine module and improves user comfort.

[0069] Optionally, the display chip can be a red display chip, a blue display chip, or a green display chip. Different grating structures can be made for different colored display chips so that the light emitted by different colored display chips has the same transmission efficiency and emission angle in the optical waveguide.

[0070] Furthermore, the method also includes:

[0071] At least one driving circuit is fabricated on a glass substrate, and the glass substrate with the at least one driving circuit is bonded to the side of the grating wafer that does not have the grating structure.

[0072] To improve the yield of the grating structure on the front side of the grating wafer, driving circuits are fabricated on a glass substrate using photolithography, acid-resistant printing, and laser engraving processes. The glass substrate with the driving circuits is then transferred to the side of the grating wafer without the grating structure via wafer bonding. The orthogonal projection of the electrodes of the driving circuits onto the grating wafer should correspond to the orthogonal projection of the coupled grating onto the grating wafer.

[0073] Furthermore, to improve the assembly yield of the display chip, a grating wafer can be diced first to obtain at least one die. Each die includes a grating structure and a driving circuit. The driving circuit can be directly fabricated on the side of the grating wafer without the grating structure, or on a glass substrate. The glass substrate with the driving circuit is then bonded to the side of the grating wafer without the grating structure. Finally, the display chip is transferred to the electrodes of the driving circuit using wafer bonding technology or mass transfer technology, completing the fabrication of the AR glasses' optical engine module. Figure 10 This is a schematic diagram illustrating a process of first dicing a grating wafer and then mounting a display chip, as provided in an embodiment of this application. Figure 10 As shown, after N grating structures and N driving circuits are fabricated on the grating wafer, the grating wafer is first divided into N dies, and then the display chip is bonded to the dies to obtain N AR glasses optical engine modules, where N is a positive integer greater than zero.

[0074] Accordingly, this application also provides a method for manufacturing a color AR glasses optical engine module. Based on the AR glasses optical engine modules described in the above embodiments, an AR glasses optical engine module with a red display chip, an AR glasses optical engine module with a blue display chip, and an AR glasses optical engine module with a green display chip are bonded together using wafer bonding technology to obtain a color AR glasses optical engine module. The bonding method between the AR glasses optical engine modules can be wafer bonding technology.

[0075] Figure 11 A flowchart illustrating another possible method for manufacturing an AR glasses optical engine module, as provided in this application embodiment. Figure 11As shown, firstly, a grating structure, including an insertion grating and an extraction grating, is fabricated on one side of the grating wafer using nanoimprint lithography. Then, a driving circuit is fabricated on the other side of the grating wafer without the grating structure. This driving circuit can be directly fabricated on the grating wafer using photolithography, or it can be fabricated on a glass substrate and then bonded to the other side of the grating wafer without the grating structure. The orthographic projection of the electrodes of the driving circuit onto the grating wafer corresponds to the orthographic projection of the insertion grating onto the grating wafer. Finally, a display chip is mounted and the grating wafer is diced to obtain the AR glasses optical engine module. The mounting of the display chip can utilize wafer bonding technology or mass transfer technology. Furthermore, it should be understood that the display chip can be mounted onto the electrodes of the driving circuit before dicing the grating wafer, or the grating wafer can be diced first to obtain dies containing only the grating structure and the driving circuit, and then the display chip can be mounted onto the electrodes of the driving circuits of each die. This application does not limit the choice between these methods.

[0076] Obviously, those skilled in the art can make various modifications and variations to this application without departing from the spirit and scope of this application. Therefore, if such modifications and variations fall within the scope of the claims of this application and their equivalents, this application also intends to include such modifications and variations.

Claims

1. A method for manufacturing an optical engine module for AR glasses, characterized in that, The method includes: At least one grating structure is fabricated on a grating wafer, wherein each of the at least one grating structure includes a coupled-in grating and a coupled-out grating; At least one driving circuit is fabricated on the side of the grating wafer without the grating structure, wherein the electrodes of the at least one driving circuit are symmetrical to the coupled grating of the at least one grating structure on both sides of the grating wafer; A display chip is mounted on the electrode of each of the at least one driving circuit; Based on the number of grating structures fabricated on the grating wafer, the grating wafer is cut to obtain at least one AR glasses optical engine module.

2. The method as described in claim 1, characterized in that, The step of fabricating at least one driving circuit on the side of the grating wafer without the grating structure includes: On the side of the grating wafer without the grating structure, at least one driving circuit is fabricated using a photolithography process; or... At least one driving circuit is fabricated on a glass substrate, and the glass substrate with the at least one driving circuit is bonded to the side of the grating wafer that does not have the grating structure.

3. The method as described in claim 1 or 2, characterized in that, The display chip is a red display chip, or a blue display chip, or a green display chip.

4. An optical engine module for augmented reality (AR) glasses, characterized in that, The AR glasses optical engine module includes an optical waveguide, a driving circuit, and a display chip. A grating structure is formed on one side of the optical waveguide and the driving circuit is formed on the other side. The grating structure includes a coupled-in grating and a coupled-out grating. The electrodes of the driving circuit are symmetrical to the coupled-in grating on both sides of the optical waveguide. The display chip is connected to the electrodes of the driving circuit. When the display chip is driven by the driving circuit, the light emitted by the display chip is coupled into the optical waveguide through the coupling grating and coupled out of the optical waveguide through the decoupling grating.

5. The AR glasses optical engine module as described in claim 4, characterized in that, The AR glasses optical engine module also includes: a glass substrate; The driving circuit is located on the glass substrate and bonded to the side of the optical waveguide that does not have the grating structure.

6. The AR glasses optical engine module as described in claim 4, characterized in that, The grating structure is fabricated on the optical waveguide using a nanoimprint lithography process.

7. The AR glasses optical engine module as described in claim 4, characterized in that, The driving circuit is fabricated on the side of the optical waveguide without the grating structure using a photolithography process.

8. The AR glasses optical engine module as described in claim 4, characterized in that, The display chip is bonded to the electrodes of the driving circuit using wafer bonding technology.

9. The AR glasses optical engine module as described in claim 4, characterized in that, The display chip is a red display chip, or a blue display chip, or a green display chip.

10. A color AR glasses optical engine module, characterized in that, The color AR glasses optical engine module includes a plurality of AR glasses optical engine modules as described in any one of claims 4-9, wherein the plurality of AR glasses optical engine modules include at least one AR glasses optical engine module configured with a red display chip, at least one AR glasses optical engine module configured with a blue display chip, and at least one AR glasses optical engine module configured with a green display chip.

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