Optical waveguide device and method thereof

Abstract

An optical waveguide device (1) and a method thereof. The optical waveguide device (1) comprises: a waveguide substrate (10), wherein the waveguide substrate (10) has a first surface (11) and a second surface (12) parallel to each other; a light coupling-in mechanism (20), wherein the light coupling-in mechanism (20) is arranged on the waveguide substrate (10), and the light coupling-in mechanism (20) has a functional surface (200) inclined relative to the first surface (11) of the waveguide substrate (10) for coupling light into the waveguide substrate (10) by reflection or refraction, so that the light is totally reflected between the first surface (11) and the second surface (12) of the waveguide substrate (10); and a grating working mechanism (30), wherein the grating working mechanism (30) is formed on the waveguide substrate (10) for diffusely coupling the light out of the waveguide substrate (10) by diffraction, so as to improve the light energy utilization efficiency while ensuring mass production.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of augmented reality technology, in particular to an optical waveguide device, a method and an apparatus thereof. BACKGROUND

[0002] Augmented reality is a technology that integrates virtual world information and real world information "seamlessly", which is to project the pixels on the micro projector into the human eye through the optical combiner, and at the same time see the real world through the optical combiner, that is, to superimpose the virtual content provided by the micro projector and the real environment in real time to exist in the same picture or space, so that the user obtains the experience of virtual and real fusion. Therefore, one of the design requirements of the optical combiner is that it cannot block the forward line of sight and has high transmittance.

[0003] The relatively mature augmented reality technology on the market at present mainly includes prism scheme, free-form surface scheme, BirdBath scheme and optical waveguide scheme. However, from the aspects of optical effect, appearance form and mass production prospect, the optical waveguide is the best augmented reality scheme at present, which has excellent development potential. As known, the basis of the optical waveguide is a light and thin transparent glass substrate (its thickness is generally several millimeters or sub-millimeter level), so that the light advances by full reflection between the upper and lower surfaces of the glass substrate, that is, when the refractive index of the transmission medium is greater than the refractive index of the surrounding medium and the incident angle in the waveguide is greater than the critical angle of total reflection, the light can be totally reflected in the optical waveguide to be transmitted without leakage. In this way, after the image light from the projector is coupled into the optical waveguide, the image light continues to propagate in the optical waveguide without loss until it is coupled out by the subsequent structure.

[0004] At present, the waveguides on the market are generally divided into geometric array waveguides and diffractive optical waveguides. The geometric array optical waveguide realizes the output of the image and the expansion of the eyebox by array mirror stacking, although the image quality and efficiency thereof can reach a high level, but it needs to be coated, stacked, cut, ground and polished on multiple half-reflective half-transmissive lens surfaces, resulting in a complicated manufacturing process flow and a low overall yield, which is not suitable for mass production in industry. The diffractive optical waveguide mainly includes a surface relief grating waveguide manufactured by using photolithography technology and a holographic volume grating waveguide manufactured based on holographic interference technology, although the diffractive optical waveguide will cause rainbow phenomenon and halo of the image due to grating diffraction, and has the problem of low efficiency, but in the production process, the diffractive optical waveguide has obvious advantages due to its high design freedom and mass producibility by nanoimprinting.

[0005] However, the existing diffraction optical waveguide, although it can use a coupling-in grating such as a rectangular grating, a sawtooth grating or an inclined grating to couple visible light into the waveguide, will result in a low waveguide coupling-in efficiency due to grating diffraction loss. For example, when the grating period of the coupling-in grating ranges from 200 nm to 1 um, and the light incident at a certain angle range is diffracted by the coupling-in grating, the coupling-in efficiency of the rectangular grating is not higher than 20%, and the coupling-in efficiencies of the sawtooth grating and the inclined grating are not higher than 40%. In addition, due to the consideration of the manufacturability in the actual process, the structure of the coupling-in grating also needs to be limited, so the final coupling-in efficiency of the coupling-in grating may be even lower. SUMMARY

[0006] An advantage of the present application is to provide an optical waveguide device, method and equipment, which can improve the light energy utilization efficiency while ensuring mass production.

[0007] Another advantage of the present application is to provide an optical waveguide device, method and equipment, wherein in an embodiment of the present application, the optical waveguide device can balance the light energy utilization efficiency and mass production, facilitating the commercialization of its utilization value.

[0008] Another advantage of the present application is to provide an optical waveguide device, method and equipment, wherein in an embodiment of the present application, the optical waveguide device can couple light into the waveguide substrate by reflection or refraction, greatly improving the coupling-in efficiency and further improving the light energy utilization efficiency.

[0009] Another advantage of the present application is to provide an optical waveguide device, method and equipment, wherein in an embodiment of the present application, the optical waveguide device can realize high-brightness image display without configuring a high-power projection light engine, thereby avoiding increasing the heat dissipation burden of the projection light engine.

[0010] Another advantage of the present application is to provide an optical waveguide device, method and equipment, wherein in an embodiment of the present application, the optical waveguide device can realize light coupling-in only by using an inclined side surface, which not only improves the light coupling-in efficiency, but also further reduces the volume and weight of the optical waveguide, so as to meet the current trend of miniaturization and thinning.

[0011] Another advantage of the present application is to provide an optical waveguide device, method and equipment, wherein in order to achieve the above-mentioned purposes, the present application does not need to use expensive materials or complex structures. Therefore, the present application successfully and effectively provides a solution, not only providing an optical waveguide device, method and equipment, but also increasing the practicability and reliability of the optical waveguide device, method and equipment.

[0012] Another advantage of the present application is to provide an optical waveguide device, method and apparatus, wherein a projection light engine of an augmented reality device is implemented as a laser beam scanning light machine, which is capable of compensating for the dispersion and distortion effects caused by the diffraction of red, green and blue light rays by a waveguide grating of the optical waveguide device, so that the three-color image projected by the laser beam scanning light machine can be normally superimposed and displayed.

[0013] To achieve at least one of the above advantages or other advantages and objects, the present application provides an optical waveguide device, comprising:

[0014] a waveguide substrate, wherein the waveguide substrate has a first surface and a second surface which are parallel to each other;

[0015] a light coupling-in mechanism, wherein the light coupling-in mechanism is arranged on the waveguide substrate, and the light coupling-in mechanism has a functional surface which is inclined with respect to the first surface of the waveguide substrate, for coupling light rays into the waveguide substrate by reflection or refraction, so that the light rays are totally reflected between the first surface and the second surface of the waveguide substrate; and

[0016] a grating working mechanism, wherein the grating working mechanism is formed on the waveguide substrate, for diffusely coupling the light rays out of the waveguide substrate by diffraction.

[0017] According to an embodiment of the present application, the waveguide substrate further has an inclined side surface, and the inclined side surface and the first surface have a preset included angle, wherein the inclined side surface of the waveguide substrate is implemented as the functional surface of the light coupling-in mechanism.

[0018] According to an embodiment of the present application, the inclined side surface of the waveguide substrate is used to face a projection light engine, so that image light rays projected by the projection light engine are refracted at the inclined side surface of the waveguide substrate to be coupled into the waveguide substrate.

[0019] According to an embodiment of the present application, the light coupling-in mechanism comprises an anti-reflection film, wherein the anti-reflection film is arranged on the inclined side surface of the waveguide substrate.

[0020] According to an embodiment of the present application, the preset included angle satisfies the following condition:

[0021]

[0022] wherein n is the refractive index of the waveguide substrate, θ0 is the preset included angle, and θ is the included angle between the image light rays and the normal of the first surface.

[0023] According to an embodiment of the present application, the light in-coupling mechanism is implemented as a reflective element, wherein the reflective element is correspondingly arranged on the inclined side surface of the waveguide substrate, and the first surface of the waveguide substrate is used to face the projection light engine, so that the image light projected by the projection light engine is reflected at the inclined side surface of the waveguide substrate to be in-coupled into the waveguide substrate.

[0024] According to an embodiment of the present application, the reflective element comprises a reflective film, wherein the reflective film is arranged on the inclined side surface of the waveguide substrate.

[0025] According to an embodiment of the present application, the reflective element further comprises a prism, wherein the reflective film is coated on the inclined surface of the prism, and the inclined surface of the prism is correspondingly attached to the inclined side surface of the waveguide substrate.

[0026] According to an embodiment of the present application, the first side surface of the prism is parallelly intersected with the second surface of the waveguide substrate, and the second side surface of the prism is perpendicularly intersected with the first surface of the waveguide substrate.

[0027] According to an embodiment of the present application, the light in-coupling mechanism is implemented as a refractive prism, wherein the refractive prism has an in-coupling side surface and an inclined surface extending obliquely relative to the in-coupling side surface, wherein the inclined surface of the refractive prism is correspondingly attached to the second surface of the waveguide substrate, and the in-coupling side surface of the refractive prism serves as the functional surface of the light in-coupling mechanism.

[0028] According to an embodiment of the present application, the grating working mechanism is implemented as a two-dimensional grating, wherein the two-dimensional grating is formed on the first surface or the second surface of the waveguide substrate, for diffracting the light transmitted in the waveguide substrate to make the light two-dimensionally and diffusively out-couple from the waveguide substrate.

[0029] According to an embodiment of the present application, the grating working mechanism is composed of a one-dimensional turning grating and a one-dimensional out-coupling grating, wherein the one-dimensional turning grating is formed on the first surface or the second surface of the waveguide substrate, for changing the direction of the light propagating in the waveguide substrate by means of diffraction and diffusing the light along one direction, and the one-dimensional out-coupling grating is correspondingly formed on the first surface or the second surface of the waveguide substrate, for diffusing and out-coupling the light turned by the one-dimensional turning grating along another direction.

[0030] According to an embodiment of the present application, the grating working mechanism is implemented as a one-dimensional out-coupling grating, wherein the one-dimensional out-coupling grating has a one-dimensional diffusion path, and the functional surface of the light in-coupling mechanism extends along a direction perpendicular to the one-dimensional diffusion path, for diffusing the light rays in-coupled via the light in-coupling mechanism along the one-dimensional diffusion path and out-coupling the light rays from the waveguide substrate.

[0031] According to another aspect of the present application, an embodiment of the present application further provides a manufacturing method of a light waveguide device, comprising steps of:

[0032] manufacturing a master plate, wherein the master plate has grating structures corresponding to the grating working mechanism to be transferred;

[0033] processing the grating working mechanism on the surface of the waveguide substrate by nano-imprinting using the master plate; and

[0034] setting a light in-coupling mechanism on the waveguide substrate, wherein the light in-coupling mechanism has a functional surface inclined relative to the surface of the waveguide substrate, for in-coupling light rays into the waveguide substrate by refraction or reflection, and the grating working mechanism is used for diffusively out-coupling the light rays from the waveguide substrate by diffraction.

[0035] According to an embodiment of the present application, a side edge of the waveguide substrate is cut out as the functional surface of the light in-coupling mechanism.

[0036] According to another aspect of the present application, the present application further provides an augmented reality device, comprising:

[0037] a device body;

[0038] a projection light engine; and

[0039] a light waveguide device, wherein the projection light engine and the light waveguide device are correspondingly set on the device body, so that image light rays provided via the projection light engine are in-coupled into the light waveguide device by refraction or reflection and out-coupled from the light waveguide device by diffraction, so that a user's eyes receive and see corresponding images.

[0040] According to an embodiment of the present application, the light waveguide device comprises:

[0041] a waveguide substrate, wherein the waveguide substrate has a first surface and a second surface parallel to each other;

[0042] a light in-coupling mechanism, wherein the light in-coupling mechanism is disposed on the waveguide substrate, and the light in-coupling mechanism has a functional surface inclined with respect to the first surface of the waveguide substrate for in-coupling light into the waveguide substrate by reflection or refraction, so that the light is totally reflected between the first surface and the second surface of the waveguide substrate; and

[0043] a light out-coupling mechanism, wherein the light out-coupling mechanism is disposed on the waveguide substrate, and the light out-coupling mechanism has a functional surface inclined with respect to the first surface of the waveguide substrate for out-coupling light from the waveguide substrate by reflection or refraction, so that the light is totally reflected between the first surface and the second surface of the waveguide substrate; and

[0044] According to an embodiment of the present application, the projection light engine comprises a laser beam scanning light machine, when the image source comprises a plurality of monochromatic images of different colors, the laser beam scanning light machine is used to modulate and project monochromatic image light of different colors, and the modulation is used to compensate for the chromatic dispersion and distortion caused by the diffraction of the monochromatic image light of different colors through the light grating working mechanism.

[0045] According to some embodiments of the present application, the laser beam scanning light machine is used to project monochromatic image light of different colors at different angles, so that when the monochromatic image light of different colors is transmitted and emitted through the light waveguide device, the monochromatic images of different colors are displayed in superposition.

[0046] According to some embodiments of the present application, the laser beam scanning light machine is used to project monochromatic image light of different colors at different angles, so that when the monochromatic image light of different colors is transmitted and emitted through the light waveguide device, the monochromatic images of different colors are displayed in superposition.

[0047] A calibration method for a laser beam scanning light machine of a light waveguide device, the calibration method comprising the steps of:

[0048] (A) projecting image light corresponding to a plurality of monochromatic images of different colors through the laser beam scanning light machine respectively, and the image light is imaged and displayed after passing through the light waveguide device respectively; and

[0049] (B) adjusting the scanning angle of the laser beam scanning light machine when projecting image light of any color of the plurality of monochromatic images of different colors, so that the display position of the monochromatic image corresponding to the image light tends to a target position, and when the display position of the monochromatic image corresponding to the image light reaches the target position, recording the corresponding scanning angle of each image pixel in the monochromatic image corresponding to the image light.

[0050] Wherein, the light waveguide device in-couples light by reflection or refraction and out-couples light by diffraction; the plurality of monochromatic images of different colors are displayed in superposition as a color image; and the adjustment of the scanning angle is used to compensate for the chromatic dispersion and distortion caused by the diffraction of the image light of different colors.

[0051] According to another aspect of the present application, the present application further provides a method for displaying an image by an augmented reality device, the augmented reality device comprising a projection light engine implemented as a laser beam scanning light machine and a light waveguide device, the light waveguide device being a hybrid light waveguide device which couples in light rays by reflection or refraction and couples out light rays by diffraction, characterized in that the method for displaying an image comprises the steps of:

[0052] projecting, by the laser beam scanning light machine, image light corresponding to monochrome images of different colors respectively according to scanning angles corresponding to the monochrome images respectively, and coupling in the image light into the light waveguide device by reflection or refraction and transmitting the image light in the light waveguide device by total reflection to a grating working mechanism and diffracting the image light out of the light waveguide device to form an image;

[0053] wherein the projection modulation of the image light by the scanning angles corresponding to the monochrome images of different colors respectively is used to compensate for chromatic dispersion and distortion caused by diffraction of the image light of different colors.

[0054] According to an embodiment of the present application, the image light projected by the laser beam scanning light machine is reflected or refracted by a reflecting film and then coupled into the light waveguide device by total reflection, transmitted to the grating working mechanism and diffracted out of the light waveguide device to display an image.

[0055] According to an embodiment of the present application, the image light projected by the laser beam scanning light machine is refracted by a refractive prism and then coupled into the light waveguide device by total reflection and diffracted out of the light waveguide device to display an image.

[0056] According to an embodiment of the present application, the light rays coupled into the light waveguide device are coupled out of the light waveguide device by a two-dimensional grating.

[0057] According to an embodiment of the present application, the light rays coupled into the light waveguide device are coupled out of the light waveguide device by one or more one-dimensional coupling-out gratings.

[0058] According to an embodiment of the present application, the light rays coupled into the light waveguide device are changed in diffusing angle by a turning grating and coupled out of the light waveguide device by a one-dimensional coupling-out grating.

[0059] Further objects and advantages of the present application will be more fully understood from the following detailed description taken in conjunction with the accompanying drawings.

[0060] These and other objects, features and advantages of the present application will become apparent from the following detailed description of the application, taken in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF DRAWINGS

[0061] Figure 1 is a perspective view of a light waveguide device according to an embodiment of the present application.

[0062] Figure 2 A light path schematic diagram of the optical waveguide device according to the above embodiment of the present application is shown.

[0063] Figure 3 A coupling-in principle schematic diagram of the optical waveguide device according to the above embodiment of the present application is shown.

[0064] Figure 4 A first variant embodiment of the optical waveguide device according to the above embodiment of the present application is shown.

[0065] Figure 5 A second variant embodiment of the optical waveguide device according to the above embodiment of the present application is shown.

[0066] Figure 6 A third variant embodiment of the optical waveguide device according to the above embodiment of the present application is shown.

[0067] Figure 7 A fourth variant embodiment of the optical waveguide device according to the above embodiment of the present application is shown.

[0068] Figure 8 A structural schematic diagram of an augmented reality device according to an embodiment of the present application, implemented as AR glasses configured with an optical waveguide device.

[0069] Figure 9 A structural schematic diagram of another augmented reality device according to an embodiment of the present application, implemented as AR-HUD configured with an optical waveguide device.

[0070] Figure 10 A flow schematic diagram of a manufacturing method of an integrated optical waveguide device according to an embodiment of the present application.

[0071] Figure 11 A schematic diagram of the calibration process of the projection light engine of the augmented reality device according to the above embodiment of the present application is shown.

[0072] Figure 12 A K-domain diagram before uncorrected dispersion and distortion of the projection light engine of the augmented reality device according to the above embodiment of the present application is shown.

[0073] Figure 13 A projection image before calibration of the projection light engine of the augmented reality device according to the above embodiment of the present application is shown.

[0074] Figure 14 An image displayed after the light projected by the projection light engine of the augmented reality device according to the above embodiment of the present application before calibration passes through the optical waveguide device is shown.

[0075] Figure 15 K-domain diagram of the corrected dispersion, distortion of the projection light engine of the augmented reality device according to the above embodiment of the present application.

[0076] Figure 16 Projected image of the projection light engine of the augmented reality device according to the above embodiment of the present application after calibration.

[0077] Figure 17 Image displayed after the light projected by the projection light engine of the augmented reality device according to the above embodiment of the present application after calibration passes through the light waveguide device. DETAILED DESCRIPTION

[0078] The following description is provided so that others skilled in the art can have the best possible understanding of the application. The following description of preferred embodiments is not intended to limit the application, but is merely provided so that others skilled in the art can understand the application. The principles described in the following description can be applied to other embodiments, variations, modifications, equivalents, and other implementations of the application without departing from the spirit and scope of the application as described in the claims.

[0079] Those skilled in the art will understand that, in the disclosure of the present application, the terms "longitudinal", "transverse", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, which are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore the above terms cannot be understood as limiting the present application.

[0080] In the present application, the term "one" in the claims and the specification should be understood as "one or more", that is, in one embodiment, the number of one element can be one, and in another embodiment, the number of the element can be multiple. Unless it is explicitly shown in the disclosure of the present application that the number of the element is only one, the term "one" cannot be understood as unique or single, and the term "one" cannot be understood as a limitation on the number.

[0081] In the description of the present application, it should be understood that "first", "second" and the like are only used for the purpose of description and should not be understood as indicating or implying relative importance. In the description of the present application, it should be noted that, unless otherwise specified and limited, "connected", "connected" should be understood in a broad sense, for example, it can be fixedly connected, or it can be detachably connected or integrally connected; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through a medium. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0082] In the description of the present application, the description of the terms "one embodiment", "some embodiments", "example", "specific example" or "some examples" means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In the present application, the illustrative description of the above terms is not necessarily for the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any suitable manner in any one or more embodiments or examples. In addition, those skilled in the art can combine and combine different embodiments or examples described in the present application and the features of different embodiments or examples without contradiction.

[0083] In recent years, with the rapid development of augmented reality technology, devices or apparatuses capable of realizing augmented reality are also more and more popular and used by people. However, although the existing geometric light waveguide can make the image quality and light energy utilization efficiency reach a high level, it cannot realize mass production due to the complicated manufacturing process flow and low overall yield, and although the existing diffraction light waveguide can realize mass production, it is difficult to meet the high quality requirements of AR products on image contrast, brightness and the like due to the low light energy coupling-in efficiency caused by grating coupling-in. Therefore, in order to solve the above problems, the present application provides a light waveguide device which can ensure mass production while improving light energy utilization efficiency, so as to better realize the balance between product performance and mass production.

[0084] Reference is made to the accompanying drawings Figures 1 to 3 As shown, the light waveguide device according to an embodiment of the present application is illustrated, wherein the light waveguide device 1 is used to transmit image light rays projected via a projection light engine 2 into a user's eye, and external environment light rays can be transmitted through the light waveguide device 1 to be incident into the user's eye, so that the user obtains an augmented reality experience.

[0085] Specifically, as Figure 1 and Figure 2As shown, the optical waveguide device 1 can include a waveguide substrate 10, an optical coupling-in mechanism 20, and a grating working mechanism 30. The waveguide substrate 10 has a first surface 11 and a second surface 12 which are parallel to each other. The optical coupling-in mechanism 20 is disposed on the waveguide substrate 10, and the optical coupling-in mechanism 20 has a functional surface 200 which is inclined with respect to the first surface 11 of the waveguide substrate 10, and is configured to couple-in light into the waveguide substrate 10 by means of reflection or refraction, so that the light is totally reflected between the first surface 11 and the second surface 12 of the waveguide substrate 10. The grating working mechanism 30 is formed on the waveguide substrate 10, and is configured to couple-out the light from the waveguide substrate 10 by means of diffraction.

[0086] It is worth noting that, since the optical coupling-in mechanism 20 of the optical waveguide device 1 couples-in light into the waveguide substrate 10 by means of reflection or refraction, the optical energy coupling-in efficiency is greatly improved, the product performance is improved, and the grating coupling-out mechanism 30 of the optical waveguide device 1 can also retain the advantage of mass production of diffractive optical waveguides, so that the optical waveguide device 1 of the present application can improve the optical energy utilization efficiency while ensuring mass production, thereby better achieving a balance between product performance and mass production.

[0087] More specifically, as shown in Figure 1 and Figure 2 According to the above embodiments of the present application, the waveguide substrate 10 further has an inclined side surface 13, and the inclined side surface 13 and the first surface 11 have a preset included angle θ0, wherein the inclined side surface 13 of the waveguide substrate 10 is configured to face the projection light engine 2, so that the image light projected by the projection light engine 2 is first refracted at the inclined side surface 13 of the waveguide substrate 10, and then totally reflected at the first surface 11 of the waveguide substrate 10, thereby totally reflecting the image light between the first surface 11 and the second surface 12 of the waveguide substrate 10.

[0088] In other words, in the above embodiments of the present application, as shown in Figure 2 the inclined side surface 13 of the waveguide substrate 10 is implemented as the functional surface 200 of the optical coupling-in mechanism 20, so that the functional surface 200 of the optical coupling-in mechanism 20 is implemented as a refractive surface. In this way, the image light projected by the projection light engine 2 is coupled into the waveguide substrate 10 by refraction of the functional surface 200 of the optical coupling-in mechanism 20; then, the image light coupled into the waveguide substrate 10 is totally reflected back and forth between the first surface 11 and the second surface 12 of the waveguide substrate 10 to be transmitted to the grating coupling-out mechanism 30; finally, the image light is coupled out of the waveguide substrate 10 by diffraction of the grating coupling-out mechanism 30 to be incident into the user's eye, so that the user can view a virtual image corresponding to the image light. It can be understood that the waveguide substrate 10 can be but not limited to be made of a light-transmitting resin material or a light-transmitting polymer material, etc.

[0089] It is worth noting that, as shown in Figure 3 when the image light with an angle of θ is incident on the inclined side surface 13 of the waveguide substrate 10 from the air, the incident angle θ1 of the image light satisfies θ1 = θ - θ0; and after being refracted by the waveguide substrate 10 with a refractive index of n at the inclined side surface 13, the refracted angle θ2 of the image light satisfies the refraction law n*sinθ2 = sinθ1; and then totally reflects in the waveguide substrate 10 at an angle of θ', where θ' = θ0 + θ2, and the angle θ' needs to satisfy the total reflection condition, i.e. n*sinθ' > 1. Therefore, in order to ensure that the image light after being refracted at the inclined side surface 13 of the waveguide substrate 10 can be totally reflected at the first surface 11 of the waveguide substrate 10, the following condition needs to be satisfied:

[0090]

[0091] wherein n is the refractive index of the waveguide substrate 10; θ0 is the included angle between the inclined side surface 13 and the first surface 11; and θ is the included angle between the image light and the normal line of the first surface 11.

[0092] Exemplarily, the inclined side surface 13 of the waveguide substrate 10 can be obtained by cutting the side edge of the waveguide substrate 10, that is, the side edge of the waveguide substrate 10 is cut into an inclined surface as the functional surface 200 of the light coupling-in mechanism 20, so that the image light projected by the projection light engine 2 is refracted at the functional surface 200 of the light coupling-in mechanism 20 to be coupled into the waveguide substrate 10, so that the coupling-in efficiency of the light coupling-in mechanism 20 of the light waveguide device 1 of the present application can be as high as 95% or more.

[0093] Preferably, as shown in Figure 2 the light coupling-in mechanism 20 can include an anti-reflection film 21, wherein the anti-reflection film 21 is arranged on the inclined side surface 13 of the waveguide substrate 10, for reducing the reflection of the image light at the inclined side surface 13 of the waveguide substrate 10, so as to increase the transmittance of the functional surface 200 of the light coupling-in mechanism 20, and help to further improve the coupling-in efficiency of the light coupling-in mechanism 20 of the light waveguide device 1. It can be understood that the anti-reflection film 21 can be arranged on the inclined side surface 13 of the waveguide substrate 10 by means of, but not limited to, coating or bonding.

[0094] According to the above embodiments of the present application, as shown in Figure 1 and Figure 2As shown, the grating mechanism 30 of the optical waveguide device 1 can be, but is not limited to, implemented as a two-dimensional grating 31, wherein the two-dimensional grating 31 is formed on the second surface 12 of the waveguide substrate 10, for diffracting the image light transmitted within the waveguide substrate 10, so that the image light transmitted within the waveguide substrate 10 is coupled out of the waveguide substrate 10 in a two-dimensional diffuse manner. It can be understood that when the image light transmitted within the waveguide substrate 10 encounters the two-dimensional grating 31 at the second surface 12 of the waveguide substrate 10, the two-dimensional grating 31 diffracts the image light into diffracted light of different diffraction orders. In this way, the diffracted light of a certain diffraction order is coupled out and enters the user's eye, while the diffracted light of other diffraction orders will continue to be transmitted with total internal reflection in different propagation directions within the waveguide substrate 10, so that it will be diffracted again when it encounters the two-dimensional grating 31, thereby realizing the two-dimensional diffuse coupling out of the waveguide substrate 10. Of course, in other examples of this application, the two-dimensional grating 31 may also be formed on the first surface 11 of the waveguide substrate 10, which will not be described in detail here.

[0095] Furthermore, the two-dimensional grating 31 can be implemented as, but is not limited to, an embossed grating or a holographic grating.

[0096] Preferably, such as Figure 2 As shown, the preset angle θ0 between the inclined side 13 and the first surface 11 is an acute angle, so that the projection light engine 2 is located on the side adjacent to the second surface 12 of the waveguide substrate 10. Image light is coupled out from the second surface 12 of the waveguide substrate 10 and incident on the user's eye. Therefore, the projection light engine 2 and the user's eye are located on the same side of the optical waveguide device 1, which facilitates configuring the projection light engine 2 and the optical waveguide device 1 as AR glasses, with the projection light engine 2 placed at the temple of the AR glasses. It is understood that in other examples of this application, the two-dimensional grating 31 can also be formed on the first surface 11 of the waveguide substrate 10, so that image light is coupled out from the first surface 11 of the waveguide substrate 10 and incident on the user's eye, thus placing the projection light engine 2 and the user's eye on opposite sides of the optical waveguide device 1.

[0097] It is worth noting that the optical coupling mechanism 20 and the grating working mechanism 30 in the optical waveguide device 1 of this application can both have other different structural forms, or be combined with the waveguide substrate 10 in other ways. In other words, the optical waveguide device 1 of the above embodiments of this application can have various modified implementations, all of which can achieve a good balance between product performance and mass production.

[0098] For example, Appendix Figure 4A first variant of the light guide device 1 according to the above embodiments of the present application is shown. Specifically, the light guide device 1 according to the first variant of the present application is different from the above embodiments of the present application in that the light in-coupling mechanism 20 can be implemented as a reflective element 22, wherein the reflective element 22 is correspondingly arranged on the inclined side surface 13 of the waveguide substrate 10, and the first surface 11 of the waveguide substrate 10 is configured to face the projection light engine 2, such that the image light rays projected via the projection light engine 2 firstly pass through the first surface 11 of the waveguide substrate 10 to be incident on the inclined side surface 13 of the waveguide substrate 10, and then are reflected by the reflective element 22 back to the first surface 11 of the waveguide substrate 10, and then are totally reflected at the first surface 11 of the waveguide substrate 10, so as to be totally reflected between the first surface 11 and the second surface 12 of the waveguide substrate 10.

[0099] Preferably, as shown in Figure 4 the reflective element 22 can include a reflective film 221, wherein the reflective film 221 is arranged on the inclined side surface 13 of the waveguide substrate 10, and is configured to reflect the image light rays, such that the image light rays incident from the first surface 11 are reflected back to the first surface 11 of the waveguide substrate 10, so as to still improve the in-coupling efficiency of the light in-coupling mechanism 20 of the light guide device 1. It can be understood that the light guide device 1 according to the first variant of the present application replaces the anti-reflection film 21 in the above embodiments with the reflective film 221, so as to couple the image light rays into the waveguide substrate 10 by reflection. In addition, the reflective element 22 can also be implemented as a mirror coated with a reflective coating.

[0100] More preferably, as shown in Figure 4 the reflective element 22 can further include a prism 222 having a slope 2221, wherein the reflective film 221 is coated on the slope 2221 of the prism 222, and the slope 2221 of the prism 222 is correspondingly attached to the inclined side surface 13 of the waveguide substrate 10, such that the reflective film 221 is located between the slope 2221 of the prism 222 and the inclined side surface 13 of the waveguide substrate 10, so as to protect the reflective film 221. At this time, the slope 2221 of the prism 222 is implemented as the functional surface 200 of the light in-coupling mechanism 20. Of course, in other examples of the present application, the reflective element 22 can also not include the prism 222, and the reflective film 221 can be directly arranged on the inclined side surface 13 of the waveguide substrate 10 by means such as coating or bonding, but is not limited thereto.

[0101] Most preferably, as shown in Figure 4As shown, the prism 222 of the reflective element 22 further has a first side surface 2222 and a second side surface 2223. When the inclined surface 2221 of the prism 222 is correspondingly attached to the inclined side surface 13 of the waveguide substrate 10, the first side surface 2222 of the prism 222 intersects the second surface 12 of the waveguide substrate 10 in parallel, and the second side surface 2223 of the prism 222 intersects the first surface 11 of the waveguide substrate 10 perpendicularly, so as to form an optical waveguide device 1 with a rectangular structure, which is helpful for use as a display lens in AR glasses.

[0102] Appendix Figure 5 A second modified embodiment of the optical waveguide device 1 according to the above embodiment of this application is shown. Specifically, compared to the embodiments described above according to this application, the optical waveguide device 1 according to the second modified embodiment of this application differs in that: the optical coupling mechanism 20 can also be implemented as a refractive prism 23, wherein the refractive prism 23 has a coupling side surface 231 and an inclined surface 232 extending obliquely relative to the coupling side surface 231, wherein the inclined surface 232 of the refractive prism 23 is correspondingly attached to the second surface 12 of the waveguide substrate 10, and the coupling side surface 231 of the refractive prism 23 serves as the functional surface 200 of the optical coupling mechanism 20, corresponding to the projection light engine 2, so that the image light projected by the projection light engine 2 is first refracted at the coupling side surface 231 of the refractive prism 23, and then propagates through the inclined surface 232 of the refractive prism 23 and the second surface 12 of the waveguide substrate 10 to the first surface 11 of the waveguide substrate 10, and then undergoes total internal reflection at the first surface 11 of the waveguide substrate 10, thereby transmitting the image light through total internal reflection between the first surface 11 and the second surface 12 of the waveguide substrate 10. It is understood that in this modified embodiment of the present application, the waveguide substrate 10 may have a rectangular structure, that is, the waveguide substrate 10 has a vertical side without the need to provide an inclined side 13.

[0103] Preferably, the inclined surface 232 of the refracting prism 23 is correspondingly glued to the second surface 12 of the waveguide substrate 10. It is understood that the refractive index of the refracting prism 23 may be the same as or different from the refractive index of the waveguide substrate 10, depending on the condition of achieving total internal reflection.

[0104] More preferably, the coupling side 231 of the refracting prism 23 is perpendicular to the projection path of the projection light engine 2, so that the image light projected by the projection light engine 2 is perpendicularly incident on the coupling side 231 of the refracting prism 23, so as to minimize the reflection of the image light by the coupling side 231 of the refracting prism 23, which helps to improve the coupling efficiency of the light coupling mechanism 20.

[0105] It is worth noting that, regardless of whether the optical coupling mechanism 20 couples the image light into the waveguide substrate 10 through refraction or reflection, the propagation direction of the coupled image light is always towards the direction away from the functional surface 200 of the optical coupling mechanism 200. For example, in the first modified embodiment described above, the propagation direction of the coupled image light is from the second side surface 2223 of the prism 222 to the first side surface 2222 of the prism 222.

[0106] Appendix Figure 6 A third modified embodiment of the optical waveguide device 1 according to the above embodiments of this application is shown. Specifically, compared with the second modified embodiment according to this application, the optical waveguide device 1 according to the third modified embodiment differs in that: the grating working mechanism 30 can be composed of a one-dimensional turning grating 32 and a one-dimensional coupling grating 33, wherein the one-dimensional turning grating 32 is formed on the first surface 11 or the second surface 12 of the waveguide substrate 10, and is used to change the direction of propagation of the image light coupled through the refractive prism 23 in the waveguide substrate 10 by diffraction, and to diffuse the image light in one direction, wherein the one-dimensional coupling grating 33 is correspondingly formed on the second surface 12 of the waveguide substrate 10, and is used to diffuse the turned image light in another direction and couple it out of the waveguide substrate 10. Of course, in other examples of this application, the one-dimensional coupling grating 33 can also be formed on the first surface 11 of the waveguide substrate 10, which will not be described in detail here.

[0107] For example, such as Figure 6 As shown, the refractive prism 23 is located at the upper left corner of the waveguide substrate 10, with the one-dimensional deflection grating 32 located to the right of the prism 222 and corresponding to the other side of the refractive prism 23. The one-dimensional coupling grating 33 is located below the one-dimensional deflection grating 32. Thus, after the image light projected by the projection light engine 2 is refracted by the refractive prism 23 and coupled into the waveguide substrate 10, the coupled image light will be transmitted from left to right by total internal reflection within the waveguide substrate 10 to the one-dimensional deflection grating 32 and be diffracted. A portion of the image light continues to be transmitted from left to right by total internal reflection to encounter the one-dimensional deflection grating 32 again and be diffracted, while another portion of the image light is deflected to be transmitted from top to bottom by total internal reflection to the one-dimensional coupling grating 33 and be diffracted to couple out of the waveguide substrate 10.

[0108] In other words, in this variant embodiment of the present application, firstly, the in-coupled image light rays are laterally transmitted in the waveguide substrate 10 to the one-dimensional turning grating 32; then, the one-dimensional turning grating 32 diffracts the laterally transmitted image light rays, so that a part of the image light rays is still laterally transmitted to be diffracted by the one-dimensional turning grating 32 again, and another part of the image light rays is longitudinally transmitted to the one-dimensional out-coupling grating 33; finally, the one-dimensional out-coupling grating 33 diffracts the longitudinally transmitted image light rays, so that a part of the image light rays continues to be longitudinally transmitted to be diffracted by the one-dimensional out-coupling grating 33 again, and another part of the image light rays is out-coupled from the waveguide substrate 10, thereby realizing two-dimensional diffused out-coupling of the image light rays from the waveguide substrate 10.

[0109] It is worth noting that in the above-mentioned embodiments and various variant embodiments of the present application, the exit pupil of the projection light engine 2 is generally small, so that the light waveguide device 1 is always realized by the grating working mechanism 30 to continuously out-pupil replicate and out-couple the projected image light rays in two dimensions, so as to obtain a large enough eyebox in two dimensions, which is convenient for users to watch. However, in other examples of the present application, the grating working mechanism 30 can only have the function of replicating and out-coupling the exit pupil in one dimension, and the projection light engine 2 has a larger exit pupil in the other dimension, so as to ensure that a large enough eyebox can still be obtained in two dimensions. At this time, the function surface 200 of the light in-coupling mechanism 20 of the light waveguide device 1 needs to be matched with the size of the exit pupil of the projection light engine 2, so as to correspondingly in-couple the image light rays projected by the projection light engine 2 into the waveguide substrate 10.

[0110] For example, as shown in FIG. 6, the light in-coupling mechanism 20 of the light waveguide device 1 according to the third variant embodiment of the present application includes a function surface 200, and the function surface 200 is perpendicular to the one-dimensional turning grating 32 and the one-dimensional out-coupling grating 33, and the function surface 200 is perpendicular to the one-dimensional turning grating 32 and the one-dimensional out-coupling grating 33. Figure 7 A fourth variant embodiment of the light waveguide device 1 according to the above-mentioned embodiments of the present application is shown. Specifically, compared with the third variant embodiment according to the present application, the difference between the light waveguide device 1 according to the fourth variant embodiment of the present application is that the grating working mechanism 30 only includes the one-dimensional out-coupling grating 33, and the one-dimensional out-coupling grating 33 has a one-dimensional diffusion path 330 for diffusing and out-coupling the image light rays along the one-dimensional diffusion path 330; wherein the function surface 200 in the light in-coupling mechanism 20 extends along the direction perpendicular to the one-dimensional diffusion path 330 of the one-dimensional out-coupling grating 33, and the exit pupil of the projection light engine 2 covers the entire function surface 200 of the light in-coupling mechanism 20, so that the light waveguide device 1 can still diffuse the image light rays in-coupled through the light in-coupling mechanism 20 out of the waveguide substrate 10, so as to obtain a large enough eyebox in two dimensions, which is convenient for users to watch.

[0111] For example, as shown in FIG. 6, the light in-coupling mechanism 20 of the light waveguide device 1 according to the third variant embodiment of the present application includes a function surface 200, and the function surface 200 is perpendicular to the one-dimensional turning grating 32 and the one-dimensional out-coupling grating 33, and the function surface 200 is perpendicular to the one-dimensional turning grating 32 and the one-dimensional out-coupling grating 33. Figure 7As shown, the refractive prism 23 extends laterally, with the one-dimensional out-coupling grating 33 being located below the refractive prism 23, and the one-dimensional diffusion path 330 of the one-dimensional out-coupling grating 33 being arranged longitudinally. At this time, the projection light engine 2 is correspondingly arranged so that the lateral exit pupil of the projection light engine 2 matches the in-coupling side surface 231 of the refractive prism 23, that is, the lateral exit pupil of the projection light engine 2 can be larger than its longitudinal exit pupil, so that the projected image light can cover the in-coupling side surface 231 of the refractive prism 23 laterally, so as to obtain an eyebox with a certain size in two-dimensional directions.

[0112] It is worth noting that the types of the one-dimensional turning grating 32 and the one-dimensional out-coupling grating 33 can be adjusted according to specific needs, for example, but not limited to, being implemented as a surface relief grating to be machined on the surface of the waveguide substrate 10 by nanoimprinting or other technologies. Of course, in other examples of the present application, the one-dimensional turning grating 32 and the one-dimensional out-coupling grating 33 can also be implemented as a holographic grating to form periodic light and dark stripes in the material by holographic exposure.

[0113] According to another aspect of the present application, as shown in Figure 8 and Figure 9 , the present application further provides an augmented reality device 4, wherein the augmented reality device 4 can include a projection light engine 2, a device body 40, and a light waveguide device 1, wherein the projection light engine 2 and the light waveguide device 1 are correspondingly arranged in the device body 40, so that the image light provided by the projection light engine 2 is coupled into the waveguide substrate 10 by the light in-coupling mechanism 20 of the light waveguide device 1, and after propagating in the waveguide substrate 10 by total reflection, it is diffusely coupled out of the waveguide substrate 10 by the grating working mechanism 30 to be received by the user's eyes to see the corresponding image.

[0114] In an example of the present application, as shown in Figure 8 , the device body 40 of the augmented reality device 4 can be implemented as a spectacle frame 41, which includes a crossbeam part 411 and a pair of temple parts 412, wherein the temple parts 412 respectively extend rearward from the left and right sides of the crossbeam part 411 to form the device body 40 with a spectacle frame structure. The light waveguide device 1 is arranged in the crossbeam part 411 as a spectacle lens for near-eye display.

[0115] Exemplarily, as shown in Figure 8 , the functional surface 200 of the light in-coupling mechanism 20 in the light waveguide device 1 corresponds to the crossbeam part 411 of the spectacle frame 41; at this time, the projection light engine 2 is mounted on the crossbeam part 411 of the spectacle frame 41, so that when the user wears the augmented reality device 4, the projection light engine 2 is correspondingly located near the user's forehead, which helps to reserve more installation space for the projection light engine 2.

[0116] It is worth noting that in addition to being implemented as AR glasses, the augmented reality device 4 can also be implemented as a head-up display (HUD). As is known, a HUD is another promising application of an optical waveguide, and in particular a vehicle-mounted HUD enables a vehicle owner to view vehicle-related information without having to lower his head while driving, so that the driver's eyes do not need to switch back and forth between the road conditions and the display, thereby ensuring safety and comfort while driving. An AR-HUD precisely combines image information with actual traffic conditions through a specially designed internal optical system, and projects information such as tire pressure, speed, and revolutions per minute to the rear of the front windshield to form a virtual image at a distance to enter the eye, so that the user can observe the prompt information integrated with the actual road conditions through the display area of the front windshield. In addition, compared with the W-HUD commonly used in the market today, the AR-HUD has a compact and thin structure, which can greatly save the installation space in the vehicle, so the AR-HUD has greater intuitiveness for the user, and by combining real road condition information, some virtual arrows and other information appear in real time to intuitively guide the driver to proceed, thereby avoiding the situation of driving through the intersection and distracting the driver's attention while driving.

[0117] In particular, the attachment Figure 9 A variant embodiment of the augmented reality device 4 according to the above embodiments of the present application is shown, in which the device body 40 of the augmented reality device 4 is implemented as a windshield 42, and the optical waveguide device 1 is correspondingly arranged on the inner side of the windshield 42, so that the image light projected by the projection light engine 2 is transmitted through the optical waveguide device 1 and then projected to the windshield 42, and is reflected inwardly through the windshield 42 to enter the eye, so that the user can see a virtual image at a relatively long distance. It can be understood that in this variant embodiment of the present application, the windshield 42 in the augmented reality device 4 can but is not limited to be implemented as a front windshield of a vehicle such as an airplane, a car, and the like, so that the augmented reality device 4 is implemented as an AR-HUD.

[0118] It is worth noting that, as with the AR glasses described above, the light waveguide device 1 in the AR-HUD of the present application couples the image light rays projected via the projection light engine 2 into the waveguide substrate 10 by reflection or refraction of the light coupling-in mechanism 20, and diffusely couples out the coupled-in image light rays from the waveguide substrate 10 by diffraction of the grating working mechanism 30, so as to improve the light energy utilization efficiency on the basis of ensuring mass producibility. Unlike the vehicle-mounted HUD configured with a common diffractive light waveguide, in order to make up for the lower light energy utilization rate to provide image light rays with greater intensity within a sufficiently large eyebox, the projection power of the projection light engine has to be greatly increased, resulting in that the projection light engine is difficult to dissipate heat due to the large power. In other words, the augmented reality device 4 of the present application only needs to use a projection light engine 2 with smaller power, and can form a high-contrast and high-quality virtual image in front of the windshield 42 for the user to view.

[0119] According to another aspect of the present application, as shown in Figure 10 The manufacturing method of the light waveguide device according to an embodiment of the present application can include the following steps:

[0120] S110: manufacturing a mother plate, wherein the mother plate has a grating structure to be transferred corresponding to the grating working mechanism 30;

[0121] S120: forming the grating working mechanism 30 on the surface of the waveguide substrate 10 by a nanoimprint method using the mother plate; and

[0122] S130: disposing a light coupling-in mechanism 20 on the waveguide substrate 10, wherein the light coupling-in mechanism 20 is configured to couple light into the waveguide substrate 10 by reflection or refraction, and the grating working mechanism 30 is configured to diffusely couple the light out of the waveguide substrate 10 by diffraction.

[0123] It is worth noting that, according to the above-mentioned embodiments of the present application, in step S110 of the manufacturing method of the light waveguide device of the present application, the mother plate can be manufactured by photolithography processing method. For example, the photolithography processing method can include, but is not limited to, laser direct writing, electron beam direct writing, mask photolithography, double-beam interference exposure, etc.

[0124] It should be noted that the light waveguide device provided by the present application is a hybrid light waveguide device, where the hybrid refers to the hybrid of geometric and diffractive ways. Specifically, the light rays emitted by the projection light engine are coupled into the waveguide substrate by reflection or refraction of the light coupling-in mechanism, and then the light rays are expanded and coupled out by the grating working mechanism in the waveguide substrate. Since the sum of the diffraction vectors of the light rays in the entire propagation process is no longer zero, the light rays will be dispersed and distorted when coupled out of the waveguide substrate. Figure 12 As shown in the K-domain diagram of the diffractive coupling-out of the color projection light from the light waveguide device, whenFigure 13 The projected image shown in the middle is projected by the projection light engine 2, and the resulting display image is shown in the right Figure 14 As shown, different color images are separated, and the images of the same color are also distorted due to diffraction, so the projection light engine 2 needs to be calibrated to reduce or eliminate the above dispersion and distortion. That is, when the image source includes a plurality of monochromatic images of different colors, the projection light engine needs to project the modulated monochromatic image light of different colors, which is used to compensate for the dispersion and distortion caused by the diffraction of the monochromatic image light of different colors by the grating working mechanism, so as to realize the superimposed display of the monochromatic images of different colors.

[0125] In practice, the present application provides a laser beam scanning light machine adapted to the optical waveguide device, which is used to modulate and project monochromatic image light of different colors, and the modulation is used to compensate for the dispersion and distortion caused by the diffraction of the monochromatic image light of different colors by the grating working mechanism.

[0126] The projection light engine 2 of the augmented reality device 4 can be implemented as a laser beam scanning light machine, which can compensate for the dispersion and distortion caused by the diffraction of monochromatic light by the waveguide grating of the grating working mechanism 30 of the optical waveguide device 1, so that the monochromatic images of different colors projected by the laser beam scanning light machine can be normally superimposed and displayed.

[0127] Laser scanning projection display technology is based on the characteristics of good collimation and directionality of laser beams, and uses a scanning device such as a rotating mirror or a galvanometer to scan the laser beam to the corresponding position at high speed, and uses the human eye's visual persistence effect to form a complete plane. The laser beam scanning light machine can include a laser light source, a light modulator, a beam scanning device, a laser beam combining device, and a controller. The image signal is loaded onto the light modulator to control the intensity of the laser beam, and the synchronization signal is loaded onto the scanning device (such as a light deflector) to make the laser beam scan according to a certain rule to form an image.

[0128] Specifically, the laser beam scanning light machine is used to project monochromatic image light of different colors at different angles, so that the monochromatic images of different colors are transmitted and emitted by the optical waveguide device, and the monochromatic images of different colors are superimposed and displayed. Further, the laser beam scanning light machine is used to scan each image pixel in the monochromatic images of different colors at different angles to project corresponding image light.

[0129] The present application also provides a calibration method for a laser beam scanning light machine adapted to an optical waveguide device, which comprises the steps of:

[0130] (A) Projecting the image light corresponding to a plurality of monochromatic images of different colors by the laser beam scanning light machine, respectively, and the image light is imaged and displayed after passing through the optical waveguide device; and

[0131] (B) in the image light of any color of the projected multiple different color single color images, adjusting the scanning angle of the laser beam scanning light machine to make the display position of the single color image corresponding to the image light tend to the target position, and recording the scanning angle corresponding to each image pixel in the single color image corresponding to the image light when the display position of the single color image corresponding to the image light reaches the target position;

[0132] Wherein, the light waveguide device couples in light rays by reflection or refraction and couples out light rays by diffraction; the multiple different color single color images are superimposed to display a color image; the adjustment of the scanning angle is used to compensate for the dispersion and distortion caused by diffraction of the image light of different colors.

[0133] Practically, step (B) comprises: in the projection of the image light corresponding to each single color image, traversing each image pixel of the single color image, for the traversed image pixel, adjusting the scanning angle of the laser beam scanning light machine to make the display position of the traversed image pixel tend to the target position, and recording the scanning angle corresponding to the traversed image pixel when the display position of the traversed image pixel reaches the target position, until the scanning angle corresponding to each image pixel of the single color image is recorded to complete the calibration of the single color image.

[0134] It can be understood that the target position in the above embodiments is a position theoretically without dispersion and distortion.

[0135] Reference Figure 11 When the multiple different color single color images comprise a red image, a green image and a blue image, the image calibration is performed after the image is coupled into the light waveguide device 1 by the laser beam scanning light machine, the dispersion and distortion of the light rays of the red, green and blue images caused by the waveguide grating of the grating working mechanism 30 of the light waveguide device 1 are compensated, and the three color images projected by the laser beam scanning light machine can be normally superimposed and displayed. The present application can realize the coupling in of image light rays by reflection or refraction and the coupling out of image light rays by diffraction without dispersion and distortion by adapting the laser beam scanning light machine to the hybrid light waveguide device.

[0136] More specifically, the calibration process of the laser beam scanning light machine comprises the following steps: the calibration image source is divided into different color single color images such as RGB three color images, and is calibrated respectively. By changing the angle of the image pixel projected by the laser beam scanning light machine, the position of the image pixel displayed after passing through the light waveguide device 1 is observed in real time, the scanning angle of the pixel is finally approximated by continuously scanning and changing the angle corresponding to the pixel, and the scanning angle (driving condition) of the pixel is solidified, and the pixel calibration is completed. Repeat this to realize the calibration of all pixels and three color images. After the calibration is completed, the light machine can directly call the driving condition of the image pixel calibration, and the final image with dispersion and distortion compensation can be obtained by coupling into the light waveguide device 1.

[0137] The present invention also provides a method for displaying images in an augmented reality device. The augmented reality device includes a projection light engine implemented as a laser beam scanning optical engine and an optical waveguide device. The optical waveguide device is a hybrid optical waveguide device, which couples in light by reflection or refraction and couples out light by diffraction. The method for displaying images includes the following steps:

[0138] The laser beam scanning optical engine projects image light corresponding to each monochrome image according to the scanning angle corresponding to each monochrome image of different colors. The image light is coupled into the optical waveguide device through reflection or refraction and is transmitted to the grating working mechanism through total internal reflection in the optical waveguide device. After being diffracted out of the optical waveguide device, it forms an image.

[0139] The scanning angle corresponding to each monochrome image of different colors modulates the projection of image light, which is used to compensate for the dispersion and distortion caused by diffraction of image light of different colors.

[0140] like Figure 15 The diagram shows the K-domain of the colored projected light coupled from the optical waveguide device after the laser beam scanning optical engine has been calibrated. Figure 16 The image shown is the projected image of the calibrated laser beam scanning device. It can be seen that the different colors in the projected image are separated and distorted. The displayed image is obtained after propagation in the optical waveguide device and coupling out by grating diffraction. Figure 17 As shown, the three-color images overlap in the displayed image to form white light, meaning the three colors can be displayed simultaneously. It is evident that the separation of the projected image by the calibrated laser beam scanning device is used to compensate for image dispersion and distortion caused by grating diffraction.

[0141] Those skilled in the art should understand that the embodiments of the present invention described above and shown in the accompanying drawings are merely examples and do not limit the present invention. The objectives of the present invention have been fully and effectively achieved. The functions and structural principles of the present invention have been demonstrated and explained in the embodiments, and any variations or modifications may be made to the implementation of the present invention without departing from the stated principles.

Claims

1. A calibration method for a laser beam scanning optomechanism of an optical waveguide device, wherein the optical waveguide device is a hybrid optical waveguide device that couples in light through reflection or refraction and couples out light through diffraction, characterized in that... The calibration method comprises steps of: (A) projecting image light corresponding to a plurality of monochromatic images of different colors respectively by the laser beam scanning optical machine, and the image light is imaged and displayed after passing through the optical waveguide device respectively; and (B) adjusting the scanning angle of the laser beam scanning optical machine to make the display position of the monochromatic image corresponding to the image light tend to a target position when the image light of any color of the plurality of monochromatic images of different colors is projected, and recording the corresponding scanning angle of each image pixel in the monochromatic image corresponding to the image light when the display position of the monochromatic image corresponding to the image light reaches the target position; wherein the target position is a display position theoretically without dispersion and distortion; the plurality of monochromatic images of different colors are displayed as a color image; the adjustment of the scanning angle is used to compensate for the dispersion and distortion caused by diffraction of the image light of different colors; and the projected image of the calibrated laser beam scanning device is separated and distorted.

2. The calibration method of claim 1, wherein, The step (B) comprises: when the image light corresponding to each monochromatic image is projected, each image pixel of the monochromatic image is traversed, and for the traversed image pixel, the scanning angle of the laser beam scanning optical machine is adjusted to make the display position of the traversed image pixel tend to the target position, and the corresponding scanning angle of the traversed image pixel is recorded when the display position of the traversed image pixel reaches the target position, until the corresponding scanning angle of each image pixel of the monochromatic image is recorded, so as to complete the calibration of the monochromatic image.

3. A method for displaying an image by an augmented reality device, the augmented reality device comprising a projection light engine implemented as a laser scanning light machine and a light guide device, the light guide device being a hybrid light guide device that couples in light rays by reflection or refraction and couples out light rays by diffraction, characterized in that, The method for displaying an image comprises steps of: after the laser beam scanning optical machine of the optical waveguide device is calibrated, the laser beam scanning optical machine projects image light corresponding to each monochromatic image of different colors respectively according to the corresponding scanning angle of each monochromatic image, the image light is coupled into the optical waveguide device by reflection or refraction and is totally reflected in the optical waveguide device to reach the grating working mechanism and is diffracted out of the optical waveguide device to be imaged; wherein the projection modulation of the image light by the corresponding scanning angle of each monochromatic image of different colors is used to compensate for the dispersion and distortion caused by diffraction of the image light of different colors; and the projected image of the calibrated laser beam scanning device is separated and distorted.

4. An augmented reality device, characterized by It comprises: a device body; a projection light engine; and an optical waveguide device; wherein the projection light engine and the optical waveguide device are correspondingly arranged in the device body; the optical waveguide device is a hybrid optical waveguide device, so that the image light provided by the projection light engine is coupled into the optical waveguide device by reflection or refraction and is coupled out by diffraction. The projection light engine comprises a laser beam scanning light machine, when the image source comprises a plurality of monochromatic images of different colors, the laser beam scanning light machine is used for modulating and projecting monochromatic image light of different colors, the modulation is used for compensating dispersion and distortion caused by diffraction of the monochromatic image light of different colors, the modulation is based on projection modulation of image light according to corresponding scanning angles of each image pixel in monochromatic images of different colors when the image pixel reaches a target position, the target position is a display position theoretically without dispersion and distortion.

5. The augmented reality device of claim 4, wherein, The laser beam scanning light machine is used for projecting monochromatic image light of different colors at different angles, so that the monochromatic images of different colors are displayed in superposition when the monochromatic image light of different colors is transmitted and emitted through the optical waveguide device.

6. The augmented reality device of claim 4, wherein the laser beam scanning light machine is used for scanning each image pixel in monochromatic images of different colors at different angles to project corresponding image light.

7. The augmented reality device of claim 4, wherein the device body is a pair of glasses or a windshield of a vehicle.

8. The augmented reality device of claim 4, wherein the optical waveguide device comprises a waveguide substrate and a light coupling-in mechanism, the light coupling-in mechanism has a functional surface inclined relative to a first surface of the waveguide substrate, so that image light is coupled in by reflection or refraction.

9. The augmented reality device of claim 8, wherein the waveguide substrate further has an inclined side surface, and the inclined side surface and the first surface have a preset included angle.

10. The augmented reality device of claim 9, wherein the light coupling-in mechanism comprises an anti-reflection film, and the anti-reflection film is arranged on the inclined side surface of the waveguide substrate.

11. The augmented reality device of claim 9, wherein the preset included angle satisfies the following condition: ， wherein n is the refractive index of the waveguide substrate; θ0 is the preset included angle; θ is the included angle between the image light and the normal line of the first surface.

12. The augmented reality device of claim 9, wherein the light coupling-in mechanism is implemented as a reflective element, the reflective element is correspondingly arranged on the inclined side surface of the waveguide substrate, and the first surface of the waveguide substrate is used to face the projection light engine, so that the image light projected through the projection light engine is reflected at the inclined side surface of the waveguide substrate to be coupled into the waveguide substrate.

13. The augmented reality device of claim 12, wherein the reflective element further comprises a prism, a reflective film is coated on the inclined surface of the prism, and the inclined surface of the prism is correspondingly attached to the inclined side surface of the waveguide substrate.

14. The augmented reality device of claim 8, wherein the light in-coupling mechanism is implemented as a refractive prism, wherein the refractive prism has an in-coupling side and an inclined surface extending obliquely with respect to the in-coupling side, wherein the inclined surface of the refractive prism is conformally fitted to the second surface of the waveguide substrate, and the in-coupling side of the refractive prism serves as the functional surface of the light in-coupling mechanism.

15. The augmented reality device of claim 8, wherein the optical waveguide apparatus further comprises a grating work structure, and the grating work structure is implemented as a two-dimensional grating, wherein the two-dimensional grating is formed on the first surface or the second surface of the waveguide substrate, wherein the second surface is parallel to the first surface.

16. The augmented reality device of claim 8, wherein the optical waveguide apparatus further comprises a grating work structure, and the grating work structure is composed of a one-dimensional turning grating and a one-dimensional out-coupling grating.

17. The augmented reality device of claim 12, wherein the optical waveguide apparatus further comprises a grating work structure, and the grating work structure is implemented as a two-dimensional grating, wherein the two-dimensional grating is formed on the first surface or the second surface of the waveguide substrate, wherein the second surface is parallel to the first surface.

18. The augmented reality device of claim 12, wherein the optical waveguide apparatus further comprises a grating work structure, and the grating work structure is composed of a one-dimensional turning grating and a one-dimensional out-coupling grating.

19. The augmented reality device of claim 14, wherein the optical waveguide apparatus further comprises a grating work structure, and the grating work structure is implemented as a two-dimensional grating, wherein the two-dimensional grating is formed on the first surface or the second surface of the waveguide substrate, wherein the second surface is parallel to the first surface.

20. The augmented reality device of claim 14, wherein the optical waveguide apparatus further comprises a grating work structure, and the grating work structure is composed of a one-dimensional turning grating and a one-dimensional out-coupling grating.

Images