Smart glasses

Abstract

The present application belongs to the technical field of glasses, and relates to a pair of smart glasses. The smart glasses comprise a glasses frame, an imaging optical module, an eye-tracking optical module and an optical waveguide module, wherein the glasses frame comprises rims and a connecting portion disposed on one side of each rim, a mounting cavity for the mounting of the imaging optical module and the eye-tracking optical module thereon being formed in the connecting portion; and the optical waveguide module is embedded in the rims, and comprises a waveguide substrate, and a first in-coupling and out-coupling grating group and a second in-coupling and out-coupling grating group, which are disposed on the waveguide substrate, at least some gratings in the first in-coupling and out-coupling grating group and the second in-coupling and out-coupling grating group being located on the same side of the waveguide substrate, and the gratings located on the same side of the waveguide substrate, namely, a first periodic grating and a second periodic grating, at least partially overlapping to form a composite grating. The smart glasses in the present application can independently couple in or out light rays of corresponding wavebands in the same region on the same side of a waveguide substrate by means of gratings of a composite grating, and thus effectively reduce the absolute area of the gratings, thereby facilitating a lightweight design and improving long-term wearing comfort.

Description

Smart glasses Technical Field

[0001] The present application relates to the field of glasses technology, and in particular to smart glasses. Background Art

[0002] Smart glasses are wearable devices that, like smartphones, have independent operating systems and can perform various functions through installed software. Taking augmented reality glasses as an example, augmented reality (AR) glasses are smart wearable devices that collect real-world information in real time and overlay virtual information and images. Through various interactive methods, they enable real-time interaction, helping people perceive information that is difficult to access in the real world. They have enormous application prospects in personal audio and video entertainment, simulation training, education, medicine, gaming, military, and aerospace fields.

[0003] To facilitate human-computer interaction and ensure that it is more in line with the shape of glasses, the display device of existing AR glasses generally includes independent display imaging devices and eye tracking devices. For example, its display imaging device includes an optical machine, an optical waveguide and a coupling-in and coupling-out grating. The virtual display image emitted by the optical machine reaches the coupling-in grating, and after diffraction by the coupling-in grating, it enters the functional layer of the optical waveguide at a specific angle, and is transmitted to the coupling-out grating for diffraction and coupling through total reflection through the functional layer of the optical waveguide, and then reaches the human eye for imaging.

[0004] In addition, existing mainstream eye tracking devices all include infrared cameras and infrared image light sources. The infrared image light source illuminates the human eye, and after being reflected by structures such as the human cornea, iris or retina, the light carrying human eye feature information will be captured by the infrared camera. After being processed by the relevant signal processor, information such as the human eye movement position can be obtained.

[0005] However, because infrared cameras need to avoid the main viewing area used for virtual display imaging, they can only be placed around AR glasses, such as in places invisible to the human body such as the eye sockets. This makes it difficult for infrared cameras to image the entire area of ​​the human eye. Therefore, it is generally necessary to set up multiple infrared cameras on the side of the eyes of the glasses, making it difficult to achieve both lightweight AR glasses and eye tracking functions.

[0006] Summary of the Invention

[0007] The purpose of the embodiments of the present application is to solve the technical problem that existing smart glasses have an eye tracking function, which results in heavy weight and large volume, making it difficult to meet the requirements of lightweight and long-term wearing.

[0008] To solve the above technical problems, the present invention provides a pair of smart glasses that adopts the following technical solutions:

[0009] The smart glasses include:

[0010] The frame includes an eye socket and a connecting portion, wherein the connecting portion is arranged on one side of the eye socket and forms a mounting cavity;

[0011] An imaging light group, disposed in the mounting cavity, for emitting imaging light with image information;

[0012] An eye tracking light assembly, disposed in the mounting cavity, for emitting infrared light and receiving infrared light carrying pupil information;

[0013] An optical waveguide group is embedded in the eye socket; the optical waveguide group includes a waveguide base and a first coupling-incoupling-outcoupling grating group and a second coupling-incoupling-outcoupling grating group provided on the waveguide base, wherein the first coupling-incoupling-outcoupling grating group is configured to couple the imaging light into and out of the waveguide base; and the second coupling-incoupling-outcoupling grating group is configured to couple the infrared light into and out of the waveguide base.

[0014] wherein at least some of the gratings in the first in-coupling / out-coupling grating group and the second in-coupling / out-coupling grating group are located on the same side of the waveguide substrate, and the gratings located on the same side of the waveguide substrate at least partially overlap;

[0015] On the same side of the waveguide substrate, the gratings in the first coupling-incoupling-outcoupling grating group that overlap with the first periodic grating are called first periodic gratings, and the gratings in the second coupling-incoupling-outcoupling grating group that overlap with the first periodic grating are called second periodic gratings; the combination of the first periodic grating and the corresponding second periodic grating is called a composite grating;

[0016] The first periodic grating and the second periodic grating both include a substrate and a plurality of microstructure units periodically arranged along a one-dimensional direction or a two-dimensional direction. The microstructure units of the first periodic grating and the microstructure units of the second periodic grating are alternately arranged on the projection surface of the substrate so that the imaging light and the infrared light are independently coupled in or out through the first periodic grating and the second periodic grating respectively on the same side and in the same area of ​​the waveguide matrix.

[0017] In a preferred solution of some embodiments, the microstructure unit of the first periodic grating is referred to as a first microstructure unit, and the first periodic grating includes N first microstructure units, and the N first microstructure units are arranged in a horizontal and / or vertical array;

[0018] In the first periodic grating, the length of a line connecting the centers of two transversely adjacent first microstructure units is a first transverse period length, and the length of a line connecting the centers of two longitudinally adjacent first microstructure units is a first longitudinal period length; the angle between a line connecting the centers of two transversely adjacent first microstructure units and a line connecting the centers of two longitudinally adjacent first microstructure units is a first periodic unit internal angle, and the first periodic unit internal angle is 90° to 150°;

[0019] The microstructure unit of the second periodic grating is called a second microstructure unit; the second periodic grating includes M second microstructure units; the M second microstructure units are arranged in a horizontal and / or vertical array;

[0020] In the second periodic grating, the length of a line connecting the centers of two laterally adjacent second microstructure units is a second lateral period length, and the length of a line connecting the centers of two longitudinally adjacent second microstructure units is a second longitudinal period length; the angle between a line connecting the centers of two laterally adjacent second microstructure units and a line connecting the centers of two longitudinally adjacent second microstructure units is a second periodic unit internal angle, and the second periodic unit internal angle is 90° to 150°;

[0021] In the composite grating, the substrate of the overlapping parts of the first period grating and the second period grating is shared.

[0022] In a preferred solution of some embodiments, in the composite grating, the first microstructure units of the first periodic grating and the second microstructure units of the second periodic grating are alternately arranged at intervals on the projection surface of the substrate;

[0023] Alternatively, the first microstructure units and the second microstructure units are alternately arranged on the projection surface of the substrate, and in the height direction of the substrate, at least part of the first microstructure units are highly overlapped with the corresponding second microstructure units.

[0024] Compared with the prior art, the smart glasses provided in the embodiments of the present application have the following advantages:

[0025] The smart glasses arrange both the imaging light group and the eye tracking light group in the mounting cavity of the frame connection part, so as to gather the eye tracking light group to the imaging light group side of the frame, so that it is located on the periphery of the frame near the eye, thereby reducing the volume and weight of the frame near the eye, which is conducive to realizing the lightweight design of the smart glasses and improving the user experience, making it convenient for users to wear them for a long time.

[0026] Furthermore, while the imaging light group and the eye-tracking light group at least partially share a waveguide matrix for propagation, the smart glasses also form a composite grating by locating at least partially the first in-coupling and out-coupling grating group and the second in-coupling and out-coupling grating group on the same side of the waveguide matrix, and the gratings on the same side at least partially overlap. The gratings on the same side and overlapping form a composite grating. The substrates of the first and second periodic gratings in the composite grating are combined into one, and their microstructure units are alternately arranged on the projection surface of the substrate. By adjusting parameters such as the size, period interval, profile, height, inclination, and incident angle of each grating in the composite grating, the gratings of the composite grating can independently couple in or out light of corresponding wavelengths on the same surface and in the same area of ​​the waveguide matrix. This effectively reduces the absolute area of ​​the gratings, achieves a miniaturized design of the optical waveguide group, and further ensures the lightweight design of the smart glasses, significantly improving the wearing comfort of the user. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the technical solutions in this application, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are some embodiments of this application or corresponding prior art. Those skilled in the art can also derive other drawings based on these drawings without inventive effort. Among them:

[0028] FIG1 is a three-dimensional exploded schematic diagram of the main parts of the smart glasses according to an embodiment of the present application;

[0029] FIG2 is a diagram illustrating the working principle of smart glasses according to the first specific implementation of Example 1 of the present application; in this diagram, the second in-coupling grating and the first out-coupling grating are coplanar and completely overlap, and the second out-coupling grating and the first in-coupling grating are coplanar and partially overlap;

[0030] FIG3 is a schematic diagram showing a principle of combining a first periodic grating and a second periodic grating in the smart glasses according to the first embodiment of the present application; in this figure, the first periodic grating and the second periodic grating have the same period and are completely interlaced;

[0031] FIG4 is a schematic diagram of a planar structure of a composite grating formed by combining the first periodic grating and the second periodic grating in FIG3 ;

[0032] FIG5 is a schematic diagram showing the arrangement of the first periodic grating and the second periodic grating of the smart glasses in the first embodiment of the present application; in this figure, the first periodic grating and the second periodic grating have the same period and are completely staggered;

[0033] FIG6 is another schematic diagram showing the principle of combining the first periodic grating and the second periodic grating in the smart glasses according to the first embodiment of the present application; in this diagram, the first periodic grating and the second periodic grating have different periods, and the heights of their microstructure units at the overlapping positions are superimposed;

[0034] FIG7 is a distribution diagram of the planar topography of a microstructure unit of a composite grating in the enhanced display glasses according to an embodiment of the present application; in this diagram, the horizontal axis represents the position of the microstructure unit, and the vertical axis represents the height of the microstructure unit;

[0035] FIG8 is a diagram illustrating the working principle of smart glasses according to the second specific implementation of Example 1 of the present application; in this diagram, the second coupling-in grating and the first coupling-out grating are coplanar and completely overlap, and the second coupling-out grating is not coplanar with the first coupling-in grating;

[0036] FIG9 is a diagram illustrating the working principle of smart glasses according to the third specific implementation of Example 1 of the present application; in this diagram, the second coupling-in grating and the first coupling-out grating are not in the same plane, and the second coupling-out grating is coplanar with and partially overlaps the first coupling-in grating;

[0037] FIG10 is a schematic diagram showing the distribution of a composite grating on a waveguide substrate of smart glasses in a first specific implementation of Example 1 of the present application;

[0038] FIG11 is a schematic diagram showing the distribution of composite gratings on a waveguide substrate of smart glasses in the second and third specific embodiments of Example 1 of the present application;

[0039] FIG12 is a diagram illustrating the working principle of the smart glasses according to the second embodiment of the present application; in this diagram, at least one composite grating is provided, and a third coupling-in grating and a third coupling-out grating are newly added to couple the light path of the light source to the waveguide substrate;

[0040] FIG13 is a schematic diagram showing the distribution principle of the composite grating on the waveguide substrate of the smart glasses in Example 2 of the present application;

[0041] FIG14 is a diagram showing a working principle of the smart glasses in the third embodiment of the present application; in this diagram, the image lens of the image imaging unit in the imaging light group is replaced with a metasurface lens;

[0042] FIG15 is a diagram illustrating the working principle of smart glasses according to the first specific implementation of the fourth embodiment of the present application; in this diagram, the pupil imaging device of the eye tracking optical system is integrated into the imaging optical system, and the second outcoupling grating is coplanar with the first incoupling grating and is located within the position of the first incoupling grating;

[0043] FIG16 is a diagram illustrating the working principle of smart glasses according to the second specific implementation of the fourth embodiment of the present application; in this diagram, the pupil imaging device of the eye tracking optical group is merged into the imaging optical group, and the second outcoupling grating is coplanar with the first incoupling grating and completely overlaps;

[0044] FIG17 is a schematic diagram showing the distribution of composite gratings on a waveguide substrate of smart glasses in a first specific implementation manner of the fourth embodiment of the present application;

[0045] FIG18 is a schematic diagram showing the distribution of composite gratings on a waveguide substrate of smart glasses in a second specific implementation manner of the fourth embodiment of the present application;

[0046] FIG19 is a diagram showing a working principle of the smart glasses in the fifth embodiment of the present application; in this diagram, the waveguide substrate is a multi-layer wave plate;

[0047] FIG20 is a schematic diagram showing the distribution principle of the composite grating on the waveguide substrate of the smart glasses in Example 5 of the present application;

[0048] FIG21 is a schematic diagram of a three-dimensional structure of the smart glasses in an embodiment of the present application.

[0049] The reference numerals in the accompanying drawings are as follows: 100, smart glasses; 200, imaging light / visible light; 300, infrared light; 400, eye; 1, frame; 11, eye socket; 111, frame hole; 12, connection part; 2, imaging light group; 21, image source; 22, image imaging unit; 221, image lens; 222, metasurface lens; 3, eye tracking light group; 31, light source; 32, pupil imaging device; 321, pupil camera; 322, dichroic mirror; 323, pupil photosensitive element; 4, optical waveguide group; 41, waveguide matrix; 411, first layer waveguide; 412, second layer waveguide; 413, visual zone; 4131, First grating region; 414, blind region; 4141, second grating region; 42, composite grating; 421, first period grating; 422, second period grating; 423, substrate; 424, first microstructure unit; 425, second microstructure unit; 43, first coupling-in grating; 431, first visible grating region; 44, first coupling-out grating; 441, second visible grating region; 45, second coupling-in grating; 451, first infrared grating region; 46, second coupling-out grating; 461, second infrared grating region; 47, third coupling-in grating; 471, third infrared grating region; 48, third coupling-out grating; 481, fourth infrared grating region; 5, temple; 6, lens; 61, diopter; 7, rubber ring. DETAILED DESCRIPTION

[0050] Unless otherwise defined, all technical and scientific terms used herein have the same meanings as commonly understood by those skilled in the art to which this application belongs. The terms used in this specification are for the purpose of describing specific embodiments only and are not intended to limit this application. For example, the directions or positions indicated by the terms "length", "width", "up", "down", "left", "right", "front", "back", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc. are based on the directions or positions shown in the accompanying drawings and are for ease of description only and should not be understood as limiting this technical solution.

[0051] The terms "including," "having," and any variations thereof in the specification, claims, and drawings of this application are intended to cover non-exclusive inclusions. The terms "first," "second," and the like in the specification, claims, and drawings of this application are used to distinguish between different items, not to describe a particular order. "Multiple" means two or more, unless otherwise expressly specified.

[0052] In the specification and claims of this application and the above-mentioned description of the drawings, when an element is referred to as being “fixed to,” “mounted on,” “disposed on,” or “connected to” another element, it may be directly or indirectly located on the other element. For example, when an element is referred to as being “connected to” another element, it may be directly or indirectly connected to the other element.

[0053] Furthermore, references to "embodiments" herein mean that a particular feature, structure, or characteristic described in connection with the embodiments may be included in at least one embodiment of the present application. The appearance of such phrases in various locations in the specification does not necessarily refer to the same embodiment, nor do they constitute independent or alternative embodiments that are mutually exclusive of other embodiments. It is understood, both explicitly and implicitly, by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0054] The embodiment of the present application provides a pair of smart glasses 100, which mainly adopts eye tracking technology based on a traditional infrared imaging camera. The smart glasses 100 not only have eye tracking functions, but also have a small overall size and weight, which can meet the requirements of lightweight and long-term wearing of the smart glasses 100.

[0055] As shown in Figures 1 and 2, the smart glasses 100 include a frame 1, an imaging light group 2, an eye tracking light group 3 and an optical waveguide group 4, wherein the frame 1 includes an eye socket 11 and a connecting portion 12, the optical waveguide group 4 is embedded in the eye socket 11, and the connecting portion 12 is arranged on one side of the eye socket 11.

[0056] Exemplarily, as shown in Figure 1, the frame 1 includes two eye sockets 11, one is the left eye socket and the other is the right eye socket, and the middle parts of the left eye socket and the right eye socket are both provided with frame holes 111, wherein the left eye socket 11 is embedded with an optical waveguide group 4 at a position corresponding to the frame hole 111, and a connecting portion 12 is provided on the left side of the left eye socket 11; the right eye socket 11 is also embedded with an optical waveguide group 4 at a position corresponding to the frame hole 111, and a connecting portion 12 is also provided on the right side of the right eye socket 11, so that the two connecting portions 12 are respectively located on the left and right sides of the frame 1 in the pupil distance direction.

[0057] As shown in FIG1 , the smart glasses 100 also include a diopter 61 and a rubber ring 7. For example, the diopter 61 is stacked with the optical waveguide assembly 4 along its thickness to form a composite lens 6 with corresponding functions. The combination of the optical waveguide assembly 4 and different types of diopter 61 creates a composite pair of glasses that can correct corresponding vision problems, such as myopia, hyperopia, astigmatism, and presbyopia, thereby expanding the user base of the smart glasses 100. Furthermore, a rubber ring 7 is provided at the insertion point between the lens 6 and the eye socket 11 to enhance the stability of the lens 6, reduce friction between the lens 6 and the eye socket 11, and prevent impurities from entering the gap between the lens 6 and the eye socket 11, thereby interfering with vision and making it difficult to clean the lens 6.

[0058] In an embodiment of the present application, based on the integrated structure of eye tracking and virtual display hardware, in order to achieve a lightweight design, each connecting portion 12 of the frame 1 is formed with a mounting cavity (not shown in the figure), and the imaging light group 2 and the eye tracking light group 3 are both arranged in the mounting cavity. Obviously, by arranging the eye tracking light group 3 on the imaging light group 2 side of the frame 1, that is, on the left and right sides of the frame 1, instead of at the eye socket 11, it is beneficial to greatly reduce the thickness and weight of the eye socket 11, thereby improving the wearing comfort of the user, and at the same time greatly reducing the difficulty of arranging devices at the eye socket 11.

[0059] Of course, in actual applications, various electronic components such as flexible circuit boards, speakers, microphones, batteries, antennas, etc. can also be placed in the mounting cavity to realize the corresponding functions of the smart reality glasses. In the embodiments of this application, the specific electronic components built into the mounting cavity and the installation details of the electronic components are not particularly limited.

[0060] In the embodiment of the present application, imaging light assembly 2 is primarily used to emit imaging light 200 carrying virtual image information, which is projected into the user's field of view through optical components such as lens 6, thereby superimposing the virtual image and the real-world image, thereby achieving an augmented reality effect. Eye tracking light assembly 3 is primarily used to emit infrared light 300 and receive infrared light 300 carrying pupil information.

[0061] It can be understood that, specifically in the embodiments of the present application, as shown in Figures 1 and 2, each eye 400 corresponds to an eye socket 11, a connecting portion 12, a waveguide matrix 41, an imaging light group 2 and an eye tracking light group 3. Since the structures corresponding to the two eyes 400 are basically the same, for the convenience of explanation, this article mainly takes one of the eyes 400 as an example for explanation.

[0062] In an embodiment of the present application, in order to achieve the propagation of the imaging light 200 and the infrared light 300 carrying virtual image information and the infrared light 300 carrying pupil information by sharing at least part of the optical path, so as to reduce the volume and weight of the smart glasses 100, the optical waveguide group 4 includes a waveguide matrix 41 and a first coupling-in-coupling-out coupling grating group and a second coupling-in-coupling-out coupling grating group arranged on the waveguide matrix 41, wherein the first coupling-in-coupling-out coupling grating group is configured to couple the imaging light 200 carrying virtual image information emitted by the imaging light group 2 into and out of the waveguide matrix 41, so as to project the imaging light 200 from the position of the waveguide matrix 41 directly facing the eye 400 to the eye 400, so as to be superimposed and displayed with the image of the real world received along the eye 400, thereby improving the user's augmented reality experience.

[0063] Similarly, the second coupling-in and coupling-out grating group is configured to couple the infrared light 300 and the infrared light 300 with pupil information into and out of the waveguide matrix 41, so as to couple the infrared light 300 directly emitted by the eye tracking light group 3, or the infrared light 300 with pupil information reflected by the eye 400 into and out of the waveguide matrix 41, so that the eye tracking light group 3 and the imaging light group 2 share at least part of the waveguide matrix 41 for signal transmission, and finally deliver the infrared light 300 with pupil information to the imaging light group side.

[0064] For example, when the infrared light 300 is projected directly from the imaging light group 2 side of the frame 1 toward the corresponding eye 400, the second coupling-in / out coupling grating group is primarily used to couple the infrared light 300 carrying pupil information reflected from the eye 400 into and out of the waveguide matrix 41, so as to be projected onto the optical device corresponding to the eye tracking light group 3 located on the imaging light group 2 side of the frame 1. When the infrared light 300 is projected from the imaging light group 2 side of the frame 1 toward the eye 400 through the waveguide matrix 41, the second coupling-in / out coupling grating group is not only primarily used to couple the infrared light 300 into and out of the waveguide matrix 41, so as to be projected onto the eye 400, but is also used to couple the infrared light 300 carrying pupil information reflected from the eye 400 to the waveguide matrix 41 into and out of the waveguide matrix 41, so as to be projected onto the optical device corresponding to the eye tracking light group 3 located on the imaging light group 2 side of the frame 1.

[0065] It can be understood that the smart glasses 100 arrange the first coupling-in coupling-out coupling grating group and the second coupling-in coupling-out coupling grating group on the waveguide matrix 41 located directly in front of the eye 400, making full use of the diffraction grating design principle of the waveguide matrix 41, so that at least part of the optical path of the imaging light group 2 and the eye tracking light group 3 is propagated through the waveguide matrix 41, so that each light coupled out from the waveguide matrix 41 is projected from directly in front of the eye 400 to the eye 400, and the infrared light 300 with pupil information reflected from the eye 400 can be projected to the waveguide matrix 41. The infrared light 300 carrying pupil information is transmitted to be projected onto the eye-tracking light group 3, thereby improving the quality of the eye-tracking light group 3 in capturing the infrared light 300 so as to have a better viewing angle range, illumination range and illumination angle, solving the problem that the pupil imaging device 32 of the eye-tracking light group 3 cannot be arranged in the center of the eye. It is also beneficial for the eye-tracking light group 3 to use fewer light sources 31 and / or pupil imaging devices 32 to achieve the same or better eye tracking effect as the traditional solution, and is also beneficial to further reduce the weight, volume and manufacturing cost of the smart glasses 100.

[0066] In an embodiment of the present application, to further reduce the size and weight of the smart glasses 100, at least some of the gratings in the first in-coupling / out-coupling grating group and the second in-coupling / out-coupling grating group are located on the same side of the waveguide substrate 41, and the gratings located on the same side of the waveguide substrate 41 at least partially overlap. Specifically, on the same side of the waveguide substrate 41, the gratings in the first in-coupling / out-coupling grating group that overlap are referred to as first-period gratings 421, and the gratings in the second in-coupling / out-coupling grating group that overlap with the first-period gratings 421 are referred to as second-period gratings 422. The combination of the first-period grating 421 and the corresponding second-period grating 422 is referred to as a composite grating 42.

[0067] In an embodiment of the present application, as shown in Figures 3 and 6, the first periodic grating 421 and the second periodic grating 422 both include a substrate 423 and a plurality of microstructure units, wherein the microstructure units are periodically arranged along a one-dimensional direction or a two-dimensional direction, and the microstructure units of the first periodic grating 421 and the microstructure units of the second periodic grating 422 are alternately arranged on the projection surface of the substrate 423, so that the imaging light 200 and the infrared light 300 are independently coupled in or out through the first periodic grating 421 and the second periodic grating 422 on the same side and in the same area of ​​the waveguide matrix 41.

[0068] Understandably, at least one composite grating 42 is provided on the waveguide substrate 41. By combining the substrates 423 of multiple gratings into one and alternately arranging the microstructure units of the multiple gratings, different wavelength bands can be modulated separately in the same area of ​​the same surface by designing the size, periodic interval, profile, height, and inclination of the microstructure units of each grating in the composite grating 42, as well as the different incident angles for different wavelength bands. This allows for independent coupling in or out of different wavelength bands in the same area on the same side. This allows for separate control of different wavelength bands while effectively reducing the absolute area of ​​the grating, thereby facilitating a miniaturized design of the optical waveguide assembly 4.

[0069] For example, in an embodiment of the present application, at least one composite grating 42 is provided on the waveguide substrate 41, wherein, by adjusting the size, period interval, profile, height, inclination angle of the microstructure units of the first period grating 421 and the second period grating 422 of the composite grating 42, and the different incident angles of the imaging light 200 and the infrared light 300, the imaging light 200 and the infrared light 300 can be modulated respectively, so as to achieve independent coupling-in or coupling-out of the imaging light 200 and the infrared light 300 in the same area on the same side.

[0070] It should be noted that the first periodic grating 421 and the second periodic grating 422 can both be one-dimensional gratings or two-dimensional gratings. Furthermore, the first periodic grating 421 can modulate the imaging light 200 independently, for example, visible light 200 in the wavelength range of 492 nm to 577 nm, but not limited to this wavelength range; the second periodic grating 422 can modulate the infrared light 300, for example, infrared light 300 in the wavelength range of 750 nm to 1000 nm, but not limited to this wavelength range.

[0071] For example, in the embodiment of the present application, the imaging light 200 is generally visible light 200. In addition, to ensure a lightweight design of the smart glasses 100, the thickness of the waveguide matrix 41 is 0.2 mm to 10 mm.

[0072] It should be noted that the waveguide substrate 41 is generally made of a transparent material, specifically, including but not limited to glass, plastic, etc. Of course, the waveguide substrate 41 can also be made of a material with a specific color, and the material of the waveguide substrate 41 is not particularly limited.

[0073] In summary, compared with the existing technology, the smart glasses 100 have at least the following beneficial effects: the smart glasses 100 arrange the imaging light group 2 and the eye tracking light group 3 in the mounting cavity of the connecting portion 12 of the frame 1, so as to gather the eye tracking light group 3 to the imaging light group 2 side of the frame 1, so that it is located on the periphery of the near-eye portion of the frame 1, thereby reducing the volume and weight of the near-eye portion of the frame 1, which is conducive to realizing the lightweight design of the smart glasses 100 and improving the user experience.

[0074] Furthermore, the smart glasses 100 not only make the imaging light group 2 and the eye tracking light group 3 at least partially share the waveguide matrix 41 for propagation, but also make the first coupling-in-coupling grating group and the second coupling-in-coupling grating group at least partially located on the same side of the waveguide matrix 41, and the gratings located on the same side at least partially overlap, so that the gratings on the same side and overlapping are combined to form a composite grating 42. In this way, the substrate 423 of the first period grating 421 and the second period grating 422 in the composite grating 42 are combined into one, and the microstructure units of the two are connected on the substrate 423. 23, so that by adjusting the size, periodic interval, profile, height, inclination of the microstructure units of each grating in the composite grating 42, and the different incident angles of different wavelengths, each grating of the composite grating 42 can independently couple in or out light of the corresponding wavelength band in the same area on the same side of the waveguide substrate 41, thereby effectively reducing the absolute area of ​​the gratings and realizing a miniaturized design of the optical waveguide group 4, thereby further ensuring the lightweight design of the smart glasses 100 and greatly improving the wearing comfort of the user.

[0075] Embodiment 1 of the smart glasses 100 of this application

[0076] In order to enable people skilled in the art to better understand the solution of this application, the technical solution in Example 1 of this application will be clearly and completely described below in conjunction with Figures 1 to 11.

[0077] In a specific implementation of the first embodiment of the present application, as shown in Figures 3 to 6 , in a composite grating 42, for ease of description, the microstructure units of the first periodic grating 421 are referred to as first microstructure units 424, and the microstructure units of the second periodic grating 422 are referred to as second microstructure units 425. To achieve an interlaced arrangement of the microstructure units of the first periodic grating 421 and the second periodic grating 422 when they are composited, the first periodic grating 421 includes N first microstructure units 424, which are arranged in a horizontal and / or vertical array. Correspondingly, the second periodic grating 422 includes M second microstructure units 425, which are arranged in a horizontal and / or vertical array.

[0078] As shown in Figure 5, in a first periodic grating 421, the length of a line connecting the centers of two laterally adjacent first microstructure units 424 is a first lateral periodic length A1, and the length of a line connecting the centers of two longitudinally adjacent first microstructure units 424 is a first longitudinal periodic length A2. Furthermore, the angle between the line connecting the centers of two laterally adjacent first microstructure units 424 and the line connecting the centers of two longitudinally adjacent first microstructure units 424 is a first periodic unit internal angle a, which is in the range of 90° to 150°.

[0079] Correspondingly, as shown in Figure 5, in a second period grating 422, the length of the line connecting the centers of two laterally adjacent second microstructure units 425 is the second lateral period length B1, and the length of the line connecting the centers of two longitudinally adjacent second microstructure units 425 is the second longitudinal period length B2; the angle between the line connecting the centers of two laterally adjacent second microstructure units 425 and the line connecting the centers of two longitudinally adjacent second microstructure units 425 is the second period unit internal angle b, and the second period unit internal angle b is 90° to 150°.

[0080] It can be understood that when designing the composite grating 42, light of different wavelength bands can be modulated directly by adjusting the first transverse period length A1, the first longitudinal period length A2, the first period unit inner angle a of the first period grating 421, and the second transverse period length B1, the second longitudinal period length B2, the second period unit inner angle b of the second period grating 422. Light of each wavelength band can be independently coupled in or out in the same area on the same side of the waveguide matrix 41.

[0081] Preferably, to simplify the composite structure of the first periodic grating 421 and the second periodic grating 422, the second transverse period length B1, second longitudinal period length B2, and second period unit internal angle b of the second periodic grating 422 are respectively the same as the first transverse period length A1, first longitudinal period length A2, and first period unit internal angle a of the first periodic grating 421. Specifically, the first transverse period length A1 of the first periodic grating 421 is preferably 150 nm to 2 μm, and the first longitudinal period length A2 is preferably 150 nm to 2 μm. Therefore, the second transverse period length B1 of the second periodic grating 422 is preferably 150 nm to 2 μm, and the second longitudinal period length B2 is preferably 150 nm to 2 μm.

[0082] It should be noted that the circles shown in FIG5 represent the corresponding positions of the microstructure units on the substrate 423 and do not represent the shape, size, height, etc. of the microstructures. Furthermore, in the composite grating 42, the shapes of the first periodic grating 421 and the second periodic grating 422 include, but are not limited to, circular, elliptical, quadrilateral, hexagonal, or other irregular shapes.

[0083] For example, in the first embodiment of the present application, as shown in Figures 3 and 6 , the first microstructure units 424 of the first periodic grating 421 and the second microstructure units 425 of the second periodic grating 422 are both cylindrical with quadrilateral cross-sections. Specifically, the side length of the first microstructure units 424 is preferably 150 nm to 2 μm, and the height is preferably 10 nm to 2 μm. Correspondingly, for the structure of the simple composite grating 42, the side length of the second microstructure units 425 of the second periodic grating 422 is also preferably 150 nm to 2 μm, and the height is also preferably 10 nm to 2 μm. That is, the first microstructure units 424 of the first periodic grating 421 and the second microstructure units 425 of the second periodic grating 422 can have the same or similar shapes and the same or different sizes, but all are within the same limited range. The size of each parameter can be adjusted according to actual needs.

[0084] In the first embodiment of the present application, in order to facilitate the combination of the first periodic grating 421 and the second periodic grating 422, simplify the structure of the composite grating 42, and reduce the absolute area and volume of the composite grating 42, in the composite grating 42, the substrate 423 of the overlapping portion of the first periodic grating 421 and the second periodic grating 422 is shared.

[0085] Exemplarily, when the first periodic grating 421 and the second periodic grating 422 completely overlap, the substrate 423 of the formed composite grating 42 is the substrate 423 of the first periodic grating 421 or the second periodic grating 422 .

[0086] Alternatively, the projection of the second periodic grating 422 on the waveguide matrix 41 is completely located within the position range of the first periodic grating 421, but the sizes of the two are different. In this case, the substrate 423 of the formed composite grating 42 is the substrate 423 of the first periodic grating 421.

[0087] Alternatively, when the first period grating 421 and the second period grating 422 partially overlap, the substrate 423 of the overlapping portion is the substrate 423 of the first period grating 421 or the second period grating 422 , and the substrate 423 of the non-overlapping portion is still the respective substrates 423 .

[0088] Preferably, in order to reduce the volume of the composite grating 42 and facilitate the lightweight design of the smart glasses 100, the thickness of the first periodic grating 421 and the second periodic grating 422 is 10 nm to 2 um.

[0089] In the composite grating 42, to achieve alternating arrangement and recombination of the microstructure units of the first periodic grating 421 and the second periodic grating 422, as shown in Figures 3 and 4, in a first specific implementation of the first embodiment of the present application, the first microstructure units 424 of the first periodic grating 421 and the second microstructure units 425 of the second periodic grating 422 are alternately arranged with gaps on the projection surface of the substrate 423. In this way, the first microstructure units 424 and the second microstructure units 425 are only periodically recombinated in the same area of ​​the substrate 423, but are not overlapped in height, that is, the first microstructure units 424 and the second microstructure units 425 still maintain their original shapes and sizes.

[0090] Alternatively, in a second specific implementation of the first embodiment of the present application, as shown in FIG6 , the first microstructure units 424 and the second microstructure units 425 are alternately arranged on the projection surface of the substrate 423, and in the height direction of the substrate 423, at least some of the first microstructure units 424 are highly overlapped with the corresponding second microstructure units 425. It is understandable that the first microstructure units 424 and the second microstructure units 425 will overlap on the projection surface of the substrate 423, and in this case, the heights of the overlapping portions will be superimposed.

[0091] For example, when the first periodic grating 421 and the second periodic grating 422 are both one-dimensional gratings, in the composite grating 42, the total height H(x) of the microstructure unit at x satisfies the shape condition constraint of the following formula 1, wherein the formula 1 is specifically as follows: H(x)=G1(x)+G2(x)………………………………Formula 1

[0092] In Formula 1, G1(x) represents the height of the first microstructure unit 424 of the first periodic grating 421 at position x; G2(x) represents the height of the second microstructure unit 425 of the second periodic grating 422 at position x. G1(x) and G2(x) satisfy the following Formulas 2 and 3, respectively:

[0093] In Formula 2, h1 represents the height of the first microstructure unit 424 of the first periodic grating 421, x1 represents the lateral offset distance of the first microstructure unit 424, and P1 represents the period of the first periodic grating 421. Formula 2 indicates that if the remainder obtained by subtracting the lateral offset distance x1 from the abscissa x of the location of the first microstructure unit 424, divided by the period P1 of the first periodic grating 421, is less than or equal to half the period of the first periodic grating 421, then the height of the first microstructure unit 424 at position x is h1; otherwise, the height is 0.

[0094] Similarly, in Formula 3, h2 represents the height of the second microstructure unit 425, x2 represents the lateral offset distance of the second microstructure unit 425, and P2 represents the period of the second periodic grating 422. Formula 3 indicates that if the remainder obtained by subtracting the lateral offset distance x2 from the abscissa x of the location of the second microstructure unit 425, divided by the period P2 of the second periodic grating 422, is less than or equal to half the period of the second periodic grating 422, then the height of the second microstructure unit 425 at position x is h2; otherwise, it is 0.

[0095] In the composite grating 42, the first periodic grating 421 and the second periodic grating 422 also satisfy the following formula 4: P(sini±sinθ)=mλ………………………………Formula 4

[0096] Specifically, in Formula 4, P represents the grating period, i represents the incident angle of the corresponding light; ± represents different diffraction spectrum types, and when the incident light and the diffracted light are on the same side of the corresponding grating normal, a positive sign is taken; otherwise, when they are on opposite sides, a negative sign is taken; θ represents the diffraction angle of the corresponding light; m represents the diffraction order, which is generally +1 or -1; λ represents the wavelength of the incident light of the corresponding light.

[0097] More specifically, the diffraction angle θ of the corresponding light must satisfy the following: the diffraction angle of the imaging light 200 is greater than the critical angle of total reflection of the light wave matrix, and the incident angle of the infrared light 300 is greater than the critical angle of total reflection of the light wave matrix.

[0098] In addition, taking the first periodic grating 421 and the second periodic grating 422 as one-dimensional gratings as an example, the total reflection law satisfies the following formula 5: sinθ0=1 / n……………………………………Formula 5

[0099] In Formula 5, θ0 represents the critical angle of total internal reflection of the light wave matrix, and n represents the refractive index of the medium. For example, if the refractive index of the medium is n = 1.5, then the critical angle of total internal reflection of the light wave matrix is ​​θ0 = 41.8°.

[0100] For example, if the incident angle of the imaging light 200 is a and the diffraction angle is b, and the incident angle of the infrared light 300 with pupil information is c and the diffraction angle is d, then: b>θ0, c>θ0.

[0101] It should be noted that, through the above formulas 1 to 5, the diffraction efficiency of the first period grating 421 and the second period grating 422 can be optimized and designed to ultimately obtain a suitable grating shape and output effect, and a total distribution pattern of the height of the composite grating 42 can also be ultimately obtained, that is, the morphology of the microstructure unit in the composite grating 42.

[0102] For example, if the period of the first period grating 421 is selected to be 490 nm, the imaging light 200 enters the waveguide matrix 41 at an incident angle of 0° to 20° that satisfies the total reflection condition, the lateral offset distance x1 of the first microstructure unit 424 of the first period grating 421 is 310 nm, and the height h1 of the first period grating 421 is 400 nm; correspondingly, the period of the second period grating 422 is selected to be 735 nm, the infrared light 300 enters the waveguide matrix 41 at an incident angle of 42° to 80°, and is diffracted and coupled out of the waveguide matrix 41 at 20° to 35°, the lateral offset distance x2 of the second microstructure unit 425 of the second period grating 422 is 410 nm, and the height h2 of the second period grating 422 is 510 nm. The height distribution regularity diagram of the final composite grating 42 can be seen in Figure 7.

[0103] It should be noted that if the first periodic grating 421 and the second periodic grating 422 are both two-dimensional gratings, their recombination principles along the x and y directions are the same as those of one-dimensional gratings, and will not be described in detail here.

[0104] In the first embodiment of the present application, as shown in Figures 2, 8 and 9, the waveguide matrix 41 can generally be a single-layer wave plate. Of course, in other embodiments, the waveguide matrix 41 can also be a multi-layer wave plate. The structure of the waveguide matrix 41 is not particularly limited here.

[0105] As shown in Figures 2, 8, and 9, to implement eye tracking, the eye tracking optical system 3 includes a light source 31 and a pupil imaging device 32. The light source 31 is primarily configured to emit infrared light 300 toward the eye 400. Specifically, in this first embodiment, the light source 31 directly emits infrared light 300 toward the eye 400. The pupil imaging device 32 is primarily configured to receive infrared light 300 emitted from the waveguide substrate 41 and carrying pupil information, thereby combining sensors and corresponding algorithms to perform gaze tracking, eye movement analysis, and eye parameter measurement on the user.

[0106] It should be noted that in the embodiments of the present application, the imaging light 200 may be visible light 200, specifically light with a wavelength of 400 nm to 650 nm. The infrared light 300 may be infrared light 300, specifically light with a wavelength of 700 nm to 1200 nm. Of course, in other embodiments, the imaging light 200 and the infrared light 300 may also be other types of light, which are not particularly limited here.

[0107] Exemplarily, when the infrared light 300 is infrared light, the light source 31 of the eye tracking light group 3 is typically an infrared light 300 source, and the pupil imaging device 32 is typically an infrared camera or an infrared video camera.

[0108] In order to project the imaging light 200 emitted by the imaging light group 2 to the eye 400 through the waveguide matrix 41, the first coupling-in coupling-out coupling grating group includes a first coupling-in grating 43 and a first coupling-out grating 44 located on the same side of the waveguide matrix 41. Specifically, the first coupling-in grating 43 and the first coupling-out grating 44 are both located on the side of the waveguide matrix 41 away from the eye 400.

[0109] In addition, in order to project the infrared light 300 carrying pupil information reflected by the eye 400 to the pupil imaging device 32 through the waveguide matrix 41, the second coupling-in coupling-out grating group includes a second coupling-in grating 45 and a second coupling-out grating 46, wherein the second coupling-in grating 45 is mainly used to couple the infrared light 300 reflected by the eye 400 to the waveguide matrix 41 for transmission, and the second coupling-out grating 46 is mainly used to couple the infrared light 300 transmitted by the waveguide matrix 41 out of the light wave matrix for reception by the pupil imaging device 32.

[0110] In embodiment 1 of the present application, as shown in Figures 2, 8 and 9, the first outcoupling grating 44 is located directly in front of the eye 400, which is conducive to the imaging light 200 with virtual image information emitted by the imaging light group 2 being coupled out of the waveguide matrix 41 through the first outcoupling grating 44, so as to be projected to the eye 400 directly in front of the eye 400, thereby facilitating the acquisition of a better virtual reality effect.

[0111] Similarly, the second coupling grating 45 is also located directly in front of the eye 400, so that the infrared light 300 with pupil information reflected by the eye 400 is directed toward the second coupling grating 45. This, on the one hand, helps the pupil imaging device 32 of the eye tracking optical group 3 obtain the infrared light 300 with pupil information from directly in front of the eye 400, solving the problem that the pupil imaging device 32 cannot be arranged in the center of the eye, thereby facilitating the use of a smaller number of pupil imaging devices 32 to obtain the same or better eye tracking effect, thereby reducing the weight and cost of the smart glasses 100; on the other hand, it also helps to reduce the illumination range and illumination angle requirements of the light source 31 of the eye tracking optical group 3.

[0112] It should be noted that, in the embodiment of the present application, the first coupling-in grating 43 and the first coupling-out grating 44 may be reflective diffraction gratings. And when the second coupling-out grating 46 is coplanar with the first coupling-in grating 43, the second coupling-out grating 46 is a reflective diffraction grating. Alternatively, when the second coupling-out grating 46 is not coplanar with the first coupling-in grating 43, the second coupling-out grating 46 is a transmissive diffraction grating. Alternatively, when the second coupling-in grating 45 is coplanar with the first coupling-out grating 44, the second coupling-in grating 45 is a reflective diffraction grating. Alternatively, when the second coupling-in grating 45 is not coplanar with the first coupling-out grating 44, the second coupling-in grating 45 is a transmissive diffraction grating.

[0113] In addition, in the first embodiment of the present application, the first coupling-in grating 43 and the first coupling-out grating 44 of the first coupling-in grating and the second coupling-out grating 45 and the second coupling-out grating 46 of the second coupling-in grating and the second coupling-out grating 46 of the second coupling-in grating and the second coupling-out grating 46 can be arranged in various configurations on the waveguide substrate 41, and the specific structures of each grating can also be varied, which are not listed here. However, regardless of the arrangement of the gratings, at least one composite grating 42 must be formed on the waveguide substrate 41, and there are various ways to form the composite grating 42, including at least the following:

[0114] In a first specific implementation of the first embodiment, the second in-coupling grating 45 is coplanar with the first out-coupling grating 44 and at least partially overlaps with it, and the second out-coupling grating 46 is coplanar with the first in-coupling grating 43. The second in-coupling grating 45 and the first out-coupling grating 44 may partially overlap or completely overlap with each other; similarly, the second out-coupling grating 46 and the first in-coupling grating 43 may partially overlap, completely overlap, or be completely offset, depending on actual needs.

[0115] It can be understood that if the second coupling-in grating 45 and the first coupling-out grating 44 are coplanar and at least partially overlap, then the second coupling-in grating 45 and the first coupling-out grating 44 together form a composite grating 42, and the first coupling-out grating 44 and the second coupling-in grating 45 are respectively the first period grating 421 and the second period grating 422 of the composite grating 42. Similarly, if the second coupling-out grating 46 and the first coupling-in grating 43 are coplanar and at least partially overlap, then the second coupling-out grating 46 and the first coupling-in grating 43 together form another composite grating 42, and the first coupling-in grating 43 and the second coupling-out grating 46 are respectively the first period grating 421 and the second period grating 422 of the composite grating 42. That is, in this case, two composite gratings 42 can be provided on the waveguide substrate 41.

[0116] It should be noted that, as shown in Figures 1 and 10, for ease of explanation and proper arrangement of the gratings of the composite grating 42 in the waveguide matrix 41, the area of ​​the waveguide matrix 41 corresponding to the eye 400 is referred to as the viewing zone 413; the area of ​​the waveguide matrix 41 corresponding to the connection portion 12 of the frame 1, which is invisible to the eye 400, is referred to as the blind zone 414. As shown in Figure 10, the area within the viewing zone 413 directly in front of the eye 400 and where the gratings are located is referred to as the first grating area 4131; the area within the blind zone 414 where the gratings are located is referred to as the second grating area 4141.

[0117] Specifically, the area corresponding to the first coupling-in grating 43 is called the first visible light grating area 431, located in the second grating area 4141; the area corresponding to the first coupling-out grating 44 is called the second visible light grating area 441, located in the first grating area 4131; the area corresponding to the second coupling-in grating 45 is called the first infrared light grating area 451, located in the first grating area 4131; and the area corresponding to the second coupling-out grating 46 is called the second infrared light grating area 461, located in the second grating area 4141. That is, the first grating area 4131 corresponds to the second visible light grating area 441 and the first infrared light grating area 451, and the second grating area 4141 corresponds to the first visible light grating area 431 and the second infrared light grating area 461.

[0118] Exemplarily, as shown in FIG2 and FIG10 , the second coupling-in grating 45 is coplanar with the first coupling-out grating 44 and completely overlaps with it, and the second coupling-out grating 46 is coplanar with the first coupling-in grating 43 and at least partially overlaps with it.

[0119] Specifically, in this example, as shown in Figures 2 and 10, the first outcoupling grating 44, the second visible grating area 441 corresponding to the first outcoupling grating 44, the second incoupling grating 45 and the first infrared grating area 451 corresponding to the second incoupling grating 45 are all located in the first grating area 4131 of the visual area 413 of the waveguide matrix 41 and are located directly in front of the eye 400; the second incoupling grating 45 and the first outcoupling grating 44 are located on the same side of the waveguide matrix 41, and the first infrared grating area 451 corresponding to the second incoupling grating 45 completely overlaps with the second visible grating area 441 corresponding to the first outcoupling grating 44.

[0120] The first coupling-in grating 43, the first visible grating area 431 corresponding to the first coupling-in grating 43, the second coupling-out grating 46 and the second infrared grating area 461 corresponding to the second coupling-out grating 46 are all located in the second grating area 4141 of the blind area 414 of the waveguide matrix 41. The second coupling-out grating 46 and the first coupling-in grating 43 are located on the same side of the waveguide matrix 41, and the projection of the second infrared grating area 461 corresponding to the second coupling-out grating 46 is located in the first visible grating area 431 corresponding to the first coupling-in grating 43 (see Figure 10), that is, the second coupling-out grating 46 partially overlaps with the first coupling-in grating 43.

[0121] Also exemplarily, in the first specific implementation of the first embodiment, the first coupling-in grating 43 and the first coupling-out grating 44 are both reflective diffraction gratings, and the second coupling-in grating 45 and the second coupling-out grating 46 are both reflective diffraction gratings, wherein the reflective diffraction gratings here include but are not limited to surface relief gratings or volume holographic gratings, etc.

[0122] In the second specific implementation of the first embodiment, as shown in Figures 8 and 11, the difference from the first specific implementation is that the second coupling-in grating 45 and the first coupling-out grating 44 are on the same plane and at least partially overlap, and the second coupling-out grating 46 and the first coupling-in grating 43 are on different planes.

[0123] In the second specific embodiment, the second coupling-in grating 45 and the first coupling-out grating 44 may partially overlap or completely overlap; similarly, the second coupling-out grating 46 and the first coupling-in grating 43 may partially overlap, completely overlap, or completely staggered when they are in different planes, depending on actual needs.

[0124] Understandably, in the second embodiment, since only the second in-coupling grating 45 is coplanar with the first out-coupling grating 44, only when the second in-coupling grating 45 and the first out-coupling grating 44 are coplanar and partially overlap, or coplanar and completely overlap, do the second in-coupling grating 45 and the first out-coupling grating 44 together form a composite grating 42. In short, this embodiment can have a composite grating 42, and the second in-coupling grating 45 and the first out-coupling grating 44 together form the composite grating 42, and the first out-coupling grating 44 and the second in-coupling grating 45 are the first period grating 421 and the second period grating 422 of the composite grating 42, respectively.

[0125] Exemplarily, as shown in FIG8 and FIG11 , the second coupling-in grating 45 is coplanar with the first coupling-out grating 44 and completely overlaps with it, and the second coupling-out grating 46 is skewed with the first coupling-in grating 43 and partially overlaps with it.

[0126] Specifically, in this example, as shown in Figures 8 and 11, the first outcoupling grating 44, the second visible grating area 441 corresponding to the first outcoupling grating 44, the second incoupling grating 45 and the first infrared grating area 451 corresponding to the second incoupling grating 45 are all located in the first grating area 4131 of the visual area 413 of the waveguide matrix 41 and are located directly in front of the eye 400; the second incoupling grating 45 and the first outcoupling grating 44 are located on the same side of the waveguide matrix 41, and the first infrared grating area 451 corresponding to the second incoupling grating 45 completely overlaps with the second visible grating area 441 corresponding to the first outcoupling grating 44.

[0127] The first coupling-in grating 43, the first visible grating area 431 corresponding to the first coupling-in grating 43, the second coupling-out grating 46 and the second infrared grating area 461 corresponding to the second coupling-out grating 46 are all located in the second grating area 4141 of the blind area 414 of the waveguide matrix 41. The second coupling-out grating 46 and the first coupling-in grating 43 are located on opposite sides of the waveguide matrix 41, and the projection part of the second infrared grating area 461 corresponding to the second coupling-out grating 46 is located in the first visible grating area 431 corresponding to the first coupling-in grating 43 (see Figure 11).

[0128] Also illustratively, the first coupling-in grating 43 and the first coupling-out grating 44 are both reflective diffraction gratings, and the second coupling-in grating 45 is a reflective diffraction grating, and the second coupling-out grating 46 is a transmissive diffraction grating, wherein the reflective diffraction gratings here include but are not limited to surface relief gratings or volume holographic gratings, and the transmissive diffraction gratings include but are not limited to surface relief gratings or volume holographic gratings.

[0129] In the third specific implementation of the first embodiment, as shown in FIG9 and FIG11 , the difference from the first specific implementation is that the second coupling-in grating 45 is not in the same plane as the first coupling-out grating 44 , and the second coupling-out grating 46 is in the same plane as the first coupling-in grating 43 and at least partially overlaps with it.

[0130] Among them, in the third specific embodiment, the second coupling-in grating 45 and the first coupling-out grating 44 can be completely staggered, partially overlapped, or completely overlapped; to form the composite grating 42, the second coupling-out grating 46 and the first coupling-in grating 43 can be partially overlapped or completely overlapped when they are on the same plane, which can be determined according to actual needs.

[0131] Understandably, in the third embodiment, since only the second outcoupling grating 46 is coplanar with the first incoupling grating 43, only when the second outcoupling grating 46 and the first incoupling grating 43 are coplanar and partially overlap, or coplanar and completely overlap, do the second outcoupling grating 46 and the first incoupling grating 43 together form a composite grating 42. In short, this embodiment can have a composite grating 42, and the second outcoupling grating 46 and the first incoupling grating 43 together form the composite grating 42, and the first incoupling grating 43 and the second outcoupling grating 46 are the first period grating 421 and the second period grating 422 of the composite grating 42, respectively.

[0132] Exemplarily, as shown in FIG9 and FIG11 , the second coupling-in grating 45 is not in the same plane as the first coupling-out grating 44 and completely overlaps with it, and the second coupling-out grating 46 is in the same plane as the first coupling-in grating 43 and partially overlaps with it.

[0133] Specifically, in this example, as shown in Figures 9 and 11, the first outcoupling grating 44, the second visible grating area 441 corresponding to the first outcoupling grating 44, the second incoupling grating 45 and the first infrared grating area 451 corresponding to the second incoupling grating 45 are all located in the first grating area 4131 of the visual area 413 of the waveguide matrix 41 and are located directly in front of the eye 400; the second incoupling grating 45 and the first outcoupling grating 44 are located on opposite sides of the waveguide matrix 41, and the first infrared grating area 451 corresponding to the second incoupling grating 45 completely overlaps with the second visible grating area 441 corresponding to the first outcoupling grating 44.

[0134] The first coupling-in grating 43, the first visible grating region 431 corresponding to the first coupling-in grating 43, the second coupling-out grating 46 and the second infrared grating region 461 corresponding to the second coupling-out grating 46 are all located in the second grating region 4141 of the blind area 414 of the waveguide matrix 41. The second coupling-out grating 46 and the first coupling-in grating 43 are located on the same side of the waveguide matrix 41, and a portion of the projection of the second infrared grating region 461 corresponding to the second coupling-out grating 46 is located within the first visible grating region 431 corresponding to the first coupling-in grating 43 (see FIG. 11 ).

[0135] Also illustratively, the first coupling-in grating 43 and the first coupling-out grating 44 are both reflective diffraction gratings, the second coupling-in grating 45 is a transmissive diffraction grating, and the second coupling-out grating 46 is a reflective diffraction grating. The reflective diffraction gratings include, but are not limited to, surface relief gratings or volume holographic gratings, and the transmissive diffraction gratings include, but are not limited to, surface relief gratings or volume holographic gratings.

[0136] In embodiment 1 of the present application, as shown in Figures 2, 8 and 9, the imaging light group 2 includes an image source 21 and an image imaging unit 22. The image imaging unit 22 is mainly used to image the imaging light 200 emitted by the image source 21, and project the imaged imaging light 200 onto a first coupling grating 43 arranged on a waveguide substrate 41.

[0137] In addition, the image forming unit 22 includes an image lens 221. Within the mounting cavity of the connecting portion 12 of the lens frame 1, the image lens 221 is disposed on the light-emitting side of the image source 21, corresponding to the blind area 414 of the waveguide matrix 41. That is, the image lens 221 is located between the image source 21 and the waveguide matrix 41. Preferably, to achieve better imaging effects, the image lens 221 is perpendicular to the image source 21 and the waveguide matrix 41.

[0138] It should be noted that the image source 21 can be a chip such as a micro LED chip, an OLED chip, an LCOS chip, an SLM chip, etc. Specifically in this embodiment, the image source 21 is preferably a self-luminous chip, such as a micro LED chip.

[0139] In the first embodiment of the present application, as shown in Figures 2, 8, and 9, the pupil imaging device 32 of the eye-tracking optical assembly 3 includes a pupil camera 321. To achieve better eye movement effects, the pupil camera 321 is disposed side by side with the imaging optical assembly 2 on the side of the frame 1, within the mounting cavity of the same connecting portion 12 of the frame 1. Preferably, the pupil camera 321 is disposed perpendicular to the corresponding waveguide substrate 41, corresponding to the blind area 414 of the waveguide substrate 41.

[0140] It should be noted that the pupil camera 321 can be one or more of various environmental detection cameras such as TOF (Time-Of-Flight) camera, RGB camera, etc. for achieving posture tracking and positioning, and is not particularly limited here.

[0141] In the first embodiment of the present application, as shown in FIG1 and FIG21 , the smart glasses 100 further include temples 5, wherein, in a specific embodiment, the temples 5 are connected to the eye sockets 11 via connecting portions 12. For example, the temples 5 and connecting portions 12 may be integrally formed, or the temples 5 and connecting portions 12 may be pivotally connected via a pivot structure, so that the temples 5 can be folded to facilitate storage of the smart glasses 100.

[0142] Alternatively, in another embodiment, the smart glasses 100 further include a strap (not shown) that can be tied to the head, wherein one end of the strap is connected to one connecting portion 12 of the frame 1, and the other end is connected to another connecting portion 12 of the frame 1. Specifically, the strap can preferably be an elastic or bendable strip-shaped strap.

[0143] For example, the left end of the strap is connected to the connection portion 12 at the left end of the frame 1, and the right end of the strap is connected to the connection portion 12 at the right end of the frame 1. In addition, for easy wearing, the middle section of the strap is detachable, that is, the strap includes two small strips of straps, wherein the two strips of straps can be detachably connected by Velcro, or connected by a pin and buttonhole buckle, etc. Of course, the middle section of the strap can also be non-detachable, that is, the strap is a whole strip of strap.

[0144] It should be noted that the temples 5 and the frame 1 may be made of materials including but not limited to pure metal, alloy, plastic or resin, and the structure of the temples 5 is not limited to the structure shown in FIG. 21 .

[0145] Embodiment 2 of the smart glasses 100 of this application

[0146] As shown in Figures 12 and 13, the main technical features of the second embodiment are substantially the same as those of the above-mentioned first embodiment. The main difference from the first embodiment is that the second coupling-in coupling-out coupling grating group further includes a third coupling-in grating 47 and a third coupling-out grating 48 arranged on the waveguide substrate 41, and the third coupling-in grating 47 is located on the same side or the opposite side of the first coupling-in grating 43; the third coupling-out grating 48 is located on the same side or the opposite side of the first coupling-out grating 44.

[0147] Among them, the third coupling-in grating 47 is mainly used to couple the infrared light 300 emitted by the light source 31 of the eye tracking light group 3 into the waveguide matrix 41; the third coupling-out grating 48 is mainly used to couple the infrared light 300 transmitted by the waveguide matrix 41 out of the waveguide matrix 41 to be incident on the eye 400.

[0148] Understandably, in this second embodiment, the infrared light 300 emitted by the light source 31 of the eye-tracking optical system 3 propagates through the waveguide matrix 41 before being projected onto the eye 400, rather than being emitted directly into the eye 400. In other words, the illumination optical path of the light source 31 is also integrated into the optical path of the waveguide matrix 41 and projected onto the eye 400 from in front of the eye 400 via the third outcoupling grating 48. Clearly, compared to a solution in which the light source 31 projects the infrared light 300 obliquely toward the eye 400, the infrared light 300 emitted by the light source 31 in this second embodiment has a better illumination angle, illumination range, and uniformity. This facilitates the use of fewer light sources 31 and / or pupil imaging devices 32 in the eye-tracking optical system 3, achieving the same or better eye tracking effect as conventional solutions. This further reduces the weight and volume of the smart glasses 100, simplifies the arrangement of components on the frame 1 near the eye, and reduces manufacturing costs.

[0149] In the second embodiment, the area corresponding to the third coupling-in grating 47 is called the third infrared grating area 471, which is located in the second grating area 4141 within the blind area 414 of the waveguide matrix 41; the area corresponding to the third coupling-out grating 48 is called the fourth infrared grating area 481, which is located in the first grating area 4131 within the viewing area 413 of the waveguide matrix 41.

[0150] When the third coupling-in grating 47 and the first coupling-in grating 43 are located on the same side of the same waveguide substrate 41, within the second grating region 4141 of the blind zone 414, the third infrared grating region 471 corresponding to the third coupling-in grating 47 and the first visible grating region 431 corresponding to the first coupling-in grating 43 may completely overlap, partially overlap, or completely staggered. Similarly, when the third coupling-out grating 48 and the first coupling-out grating 44 are located on the same side of the waveguide substrate 41, within the first grating region 4131 of the viewing zone 413, the fourth infrared grating region 481 corresponding to the third coupling-out grating 48 and the second visible grating region 441 corresponding to the first coupling-out grating 44 may completely overlap, partially overlap, or completely staggered. In short, it is sufficient to ensure that the distribution area of ​​each grating and the corresponding coupling-in and coupling-out angles of the light can prevent optical path interference or obstruction between the infrared light 300 and the imaging light 200.

[0151] It should be noted that if the third coupling grating 47 and the first coupling grating 43 are located on the same side of the same waveguide substrate 41, and the third infrared grating region 471 corresponding to the third coupling grating 47 partially overlaps or completely overlaps with the first visible grating region 431 corresponding to the first coupling grating 43, then the third coupling grating 47 and the first coupling grating 43 can also be combined to form a composite grating 42. If the third outcoupling grating 48 and the first outcoupling grating 44 are located on the same side of the same waveguide matrix 41, and the fourth infrared grating region 481 corresponding to the third outcoupling grating 48 partially overlaps or completely overlaps with the second visible grating region 441 corresponding to the first outcoupling grating 44, then the third outcoupling grating 48 and the first outcoupling grating 44 can also be combined to form a composite grating 42, so as to facilitate the infrared light 300 directly emitted by the light source 31 and the first grating carrying image information to be independently coupled into and / or coupled out of the waveguide matrix 41 in the same area of ​​the composite grating 42.

[0152] For example, as shown in FIG12 , the main difference between the working principle of the smart glasses 100 of the second embodiment and the working principle of the smart glasses 100 of the first embodiment is that the light source 31 of the eye-tracking optical group 3 projects the infrared light 300 toward the eye 400 in a different manner, as follows:

[0153] In the second embodiment, as shown in FIG12 , the light source 31 of the eye-tracking optical group 3 projects infrared light 300 (specifically, infrared light) within the mounting cavity toward a third coupling-in grating 47 disposed within a blind zone 414 of the waveguide substrate 41. The third coupling-in grating 47 couples the infrared light 300 into the functional layer of the waveguide substrate 41, and the infrared light 300 is totally reflected within the functional layer of the waveguide substrate 41 at a specific incident angle and propagates to the first grating area 4131 within the viewing zone 413 of the waveguide substrate 41. The infrared light 300 is then coupled out of the waveguide substrate 41 in front of the eye 400 through the third coupling-out grating 48 within the first grating area 4131, so that the infrared light 300 is ultimately projected directly from in front of the eye 400 to the eye 400.

[0154] Also exemplarily, as shown in FIG12 , taking the first specific implementation based on Example 1 as an example, the third coupling-in grating 47 is on the opposite side of the first coupling-in grating 43 , and the third coupling-out grating 48 is on the opposite side of the first coupling-out grating 44 .

[0155] Specifically, as shown in Figures 12 and 13, the third coupling-in grating 47, the third infrared grating area 471 corresponding to the third coupling-in grating 47, the second coupling-out grating 46, the second infrared grating area 461 corresponding to the second coupling-out grating 46, the first coupling-in grating 43, and the first visible grating area 431 corresponding to the first coupling-in grating 43 are all located in the second grating area 4141 of the blind area 414 of the waveguide matrix 41, wherein the light source 31 of the eye tracking light group 3 and the imaging light group 2 are located on the same side of the waveguide matrix 41, the third coupling-in grating 47 is located on the opposite side of the first coupling-in grating 43 and the second coupling-out grating 46, and the third infrared grating area 471 corresponding to the third coupling-in grating 47 is completely staggered with the second infrared grating area 461 corresponding to the second coupling-out grating 46 (see Figure 13).

[0156] The third out-coupling grating 48, the fourth infrared grating area 481 corresponding to the third out-coupling grating 48, the second in-coupling grating 45, the first infrared grating area 451 corresponding to the second in-coupling grating 45, the first out-coupling grating 44, and the second visible grating area 441 corresponding to the first out-coupling grating 44 are all located in the first grating area 4131 of the viewing area 413 of the waveguide matrix 41, wherein the third out-coupling grating 48 is located on the opposite side of the first out-coupling grating 44 and the second in-coupling grating 45, and the fourth infrared grating area 481 corresponding to the third out-coupling grating 48 is completely staggered with the first infrared grating area 451 corresponding to the second in-coupling grating 45 (see Figure 13).

[0157] In the second embodiment, the first coupling-in grating 43 and the first coupling-out grating 44 are reflective diffraction gratings. Furthermore, when the second coupling-in grating 45 is on the same side as the first coupling-out grating 44, the second coupling-in grating 45 is a reflective diffraction grating; alternatively, when the second coupling-in grating 45 is on the opposite side of the first coupling-out grating 44, the second coupling-in grating 45 is a transmissive diffraction grating.

[0158] When the second outcoupling grating 46 is on the same side as the first incoupling grating 43, the second outcoupling grating 46 is a reflective diffraction grating; or, when the second outcoupling grating 46 is on the opposite side of the first incoupling grating 43, the second outcoupling grating 46 is a transmissive diffraction grating.

[0159] When the third coupling grating 47 is on the same side as the first coupling grating 43 , the third coupling grating 47 is a reflective diffraction grating; or when the third coupling grating 47 is on the opposite side to the first coupling grating 43 , the third coupling grating 47 is a transmissive diffraction grating.

[0160] When the third outcoupling grating 48 is on the same side as the first outcoupling grating 44, the third outcoupling grating 48 is a reflective diffraction grating; or, when the third outcoupling grating 48 is on the opposite side of the first outcoupling grating 44, the third outcoupling grating 48 is a transmissive diffraction grating.

[0161] For example, in a first specific implementation of the second embodiment, the first coupling-in grating 43 and the first coupling-out grating 44 are both reflective diffraction gratings, wherein the reflective diffraction gratings include, but are not limited to, surface relief gratings or volume holographic gratings. The second coupling-in grating 45, the second coupling-out grating 46, the third coupling-in grating 47, and the third coupling-out grating 48 are all transmissive diffraction gratings, wherein the transmissive diffraction gratings include, but are not limited to, surface relief gratings or volume holographic gratings.

[0162] It should be noted that in the second specific implementation of this embodiment 2, the light source 31 of the eye-tracking optical group 3 and the imaging optical group 2 can also be located on opposite sides of the waveguide substrate 41. The operating principle of this second specific implementation is the same as that of the first specific implementation and will not be repeated here.

[0163] Embodiment 3 of the smart glasses 100 of this application

[0164] The main technical features of the third embodiment are substantially the same as those of the first and second embodiments. The main difference lies in the specific structure of the imaging light group 2, as follows:

[0165] As shown in Figure 14, in order to further simplify the structure of the smart glasses 100 to reduce its volume and weight, as shown in Figure 11, the image imaging unit 22 of the imaging light group 2 includes at least one metasurface lens 222, wherein the metasurface lens 222 is arranged on the light output side of the image source 21.

[0166] It can be understood that in this fourth embodiment, one or more metasurface lenses 222, or a combination of an ordinary lens and at least one metasurface lens 222, are mainly used to replace the image lens 221 of the image imaging unit 22 in the above-mentioned first and second embodiments, so as to further reduce the volume and weight of the smart glasses 100, which is conducive to further improving the wearing comfort of the user.

[0167] Embodiment 4 of the smart glasses 100 of this application

[0168] The main technical features of the fourth embodiment are substantially the same as those of the first, second, and third embodiments described above. The main difference lies in the structure and arrangement of the pupil imaging device 32 of the eye tracking optical group 3, as follows:

[0169] As shown in Figures 15 to 18, in this fourth embodiment, in order to further simplify the arrangement of devices near the eye of the frame 1 of the smart glasses 100, that is, on the eye socket 11, the pupil imaging device 32 of the eye tracking optical group 3 includes a dichroic mirror 322 and a pupil photosensitive element 323. Specifically, at a position corresponding to the blind spot 414 of the waveguide matrix 41, the imaging light 200 emitted by the image source 21 of the imaging light group 2 is transmitted through the dichroic mirror 322 into the image imaging unit 22 of the imaging light group 2; the infrared light 300 is coupled out of the waveguide matrix 41 through the second outcoupling grating 46, and then sequentially enters the image imaging unit 22 and the dichroic mirror 322, and is reflected by the dichroic mirror 322 to reach the pupil photosensitive element 323.

[0170] It can be understood that in this fourth embodiment, the pupil imaging device 32 of the eye tracking optical group 3 is incorporated into the imaging optical group 2. Specifically, the image lens 221 of the pupil imaging device 32 is replaced by a dichroic mirror 322 and a pupil photosensitive element 323, and the dichroic mirror 322 and the pupil photosensitive element 323 are arranged between the image source 21 and the image imaging unit 22 of the imaging optical group 2 to integrate the pupil imaging functional parts of the pupil imaging device 32 into the imaging optical group 2, thereby reducing the number of pupil cameras 321 of the eye tracking optical group 3 and simplifying the arrangement of devices on the eye socket 11.

[0171] For example, as shown in FIG15 and FIG16 , the main difference in the working principle of the smart glasses 100 of the fourth embodiment compared with the working principles of the smart glasses 100 in the first, second, and third embodiments is that the manner and path of the imaging light 200 emitted by the image source 21 projecting to the first coupling grating 43, and the manner and path of the pupil imaging device 32 of the eye tracking optical group 3 receiving the infrared light 300 carrying pupil information are different, as follows:

[0172] The imaging light 200 (specifically, visible light 200) emitted by the image source 21 and carrying virtual image information must first penetrate the dichroic mirror 322, and then pass through the image imaging unit 22 of the imaging light group 2 to enter the second grating area 4141 in the blind area 414 of the waveguide matrix 41, and then be coupled in by the first coupling grating 43, propagated by total reflection from the functional layer of the waveguide matrix 41, and coupled out of the waveguide matrix 41 by the first coupling grating 44, finally achieving imaging of the eye 400.

[0173] In addition, the infrared light 300 carrying pupil information reflected by the eye 400 is sequentially coupled in by the second coupling grating 45, propagated by total reflection from the functional layer of the waveguide matrix 41, coupled out of the waveguide matrix 41 by the second coupling grating 46, and then incident on the dichroic mirror 322 through the image imaging unit 22 of the imaging light group 2, and is reflected by the dichroic mirror 322 to the pupil photosensitive element 323 for imaging.

[0174] It should be noted that in the imaging light group 2, since the outgoing light path of the imaging light 200 is partially identical to the incoming light path of the infrared light 300, in order to ensure the compactness of the structure of the smart glasses 100 and reduce the overall weight and volume, in the blind area 414 of the waveguide substrate 41, the first visible light grating area 431 corresponding to the first coupling grating 43 and the second infrared grating area 461 corresponding to the second coupling grating 46 at least partially overlap.

[0175] Specifically, in the first specific embodiment, as shown in Figures 15 and 17, the projection of the second out-coupling grating 46 is completely located within the first visible light grating area 431 corresponding to the first in-coupling grating 43, and the area of ​​the second infrared grating area 461 corresponding to the second out-coupling grating 46 is smaller than the area of ​​the first visible light grating area 431 corresponding to the first in-coupling grating 43.

[0176] Alternatively, in a second specific embodiment, as shown in FIG. 16 and FIG. 18 , the first visible light grating region 431 corresponding to the first coupling-in grating 43 completely overlaps with the second infrared light grating region 461 corresponding to the second coupling-out grating 46 .

[0177] It should also be noted that pupil photosensitive element 323 can effectively image light in the 400nm-1200nm wavelength range. Preferably, pupil photosensitive element 323 can be a CMOS or CCD. Furthermore, dichroic mirror 322 undergoes a special coating process. As shown in Figures 15 and 16 , in this fourth embodiment, dichroic mirror 322 is positioned at a 45° angle between the light-emitting surface of image source 21 of imaging light assembly 2 and image forming unit 22.

[0178] Embodiment 5 of the smart glasses 100 of this application

[0179] The main technical features of the fifth embodiment are substantially the same as those of the first, second, third, and fourth embodiments described above. The main difference lies in the different structure of the waveguide matrix 41. Accordingly, the propagation path of the infrared light 300 carrying pupil information in the waveguide matrix 41 is different, as follows:

[0180] As shown in Figures 19 and 20 , in this fifth embodiment, the waveguide substrate 41 is a multilayer wave plate, wherein the first in-coupling and out-coupling grating group is located between two adjacent wave plates. It should be noted that this fifth embodiment achieves the same effects as the first embodiment, with only a slight increase in the overall volume of the smart glasses 100, but with reduced technical difficulty.

[0181] In addition, in order to form a composite grating 42 on the waveguide substrate 41 and further reduce the volume and weight of the smart glasses 100, illustratively, as shown in FIG19 , the second coupling-incoupling-outcoupling grating group is also located between two adjacent layers of wave plates, so that at least one grating corresponding to the first coupling-incoupling-outcoupling grating group is arranged to be coplanar and partially overlapped.

[0182] Preferably, as shown in FIG19 , when the waveguide matrix 41 is a multi-layer wave plate, the waveguide matrix 41 includes a first waveguide layer 411 and a second waveguide layer 412, wherein the second waveguide layer 412 is stacked on the first waveguide layer 411 along the thickness direction. The first incoupling grating 43 and the first outcoupling grating 44 are disposed on the side of the first waveguide layer 411 facing the second waveguide layer 412, that is, between the first waveguide layer 411 and the second waveguide layer 412. The second incoupling grating 45 is coplanar with the first outcoupling grating 44 and at least partially overlaps with it, and / or the second outcoupling grating 46 is coplanar with the first incoupling grating 43 and at least partially overlaps with it.

[0183] It can be understood that the second coupling-in grating 45 and the second coupling-out grating 46 are both arranged between the first waveguide layer 411 and the second waveguide layer 412 , that is, coplanar with the first coupling-out grating 44 and the first coupling-in grating 43 , respectively.

[0184] Exemplarily, as shown in FIG19 , between the first waveguide layer 411 and the second waveguide layer 412 , the first coupling-in grating 43 and the second coupling-out grating 46 are coplanar but completely offset, and the first coupling-out grating 44 and the second coupling-in grating 45 are coplanar and completely overlap to form another composite grating 42 .

[0185] It can be understood that, as shown in Figures 19 and 20, the first coupling-in grating 43, the first visible grating area 431 corresponding to the first coupling-in grating 43, the second coupling-out grating 46, and the second infrared grating area 461 corresponding to the second coupling-out grating 46 are all located in the second grating area 4141 of the blind area 414, and the first visible grating area 431 and the second infrared grating area 461 are completely staggered; the first coupling-out grating 44, the second visible grating area 441 corresponding to the first coupling-out grating 44, the second coupling-in grating 45, and the first infrared grating area 451 corresponding to the second coupling-in grating 45 are all located in the first grating area 4131 of the viewing area 413.

[0186] Of course, in other cases, the first coupling-in grating 43 and the second coupling-out grating 46 may also be coplanar and at least partially overlap to form a composite grating 42, and the first coupling-out grating 44 and the second coupling-in grating 45 may be coplanar and completely or partially overlap to form another composite grating 42.

[0187] In summary, it can be understood that in order to achieve lightweight smart glasses 100 on the basis of having eye tracking function, smart glasses 100 can replace and use at least two combinations of the above-mentioned embodiments one, two, three, four, five and the prior art, for example, different distribution area settings of gratings, different illumination modes of the light source 31 of the eye tracking light group 3, a two-in-one design of the pupil imaging device 32 of the eye tracking light group 3 and the imaging light group 2, a metasurface lens 222 replacing the image lens 221, a multi-layer wave plate replacing a single-layer wave plate, etc.

[0188] The foregoing is merely a preferred embodiment of the present application and is not intended to limit the present application. Various modifications and variations are possible for those skilled in the art. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present application should be included within the scope of the claims of the present application.

Claims

1. An intelligent glasses, characterized in that, The smart glasses include: a frame, including an eye socket and a connecting part, the connecting part being arranged on one side of the eye socket and forming an installation cavity; an imaging optical group, arranged in the installation cavity and configured to emit imaging light rays carrying image information; an eye movement tracking optical group, arranged in the installation cavity and configured to emit infrared light rays and receive infrared light rays carrying pupil information; a waveguide group, embedded in the eye socket; the waveguide group includes a waveguide substrate and a first coupling-in / coupling-out grating group and a second coupling-in / coupling-out grating group arranged on the waveguide substrate, the first coupling-in / coupling-out grating group being configured to couple the imaging light rays into and out of the waveguide substrate; the second coupling-in / coupling-out grating group being configured to couple the infrared light rays into and out of the waveguide substrate; wherein, at least some of the gratings in the first coupling-in / coupling-out grating group and the second coupling-in / coupling-out grating group are located on the same side of the waveguide substrate, and at least some of the gratings located on the same side of the waveguide substrate overlap; on the same side of the waveguide substrate, the gratings with overlapping positions in the first coupling-in / coupling-out grating group are called first periodic gratings, and the gratings in the second coupling-in / coupling-out grating group that overlap with the first periodic gratings are called second periodic gratings; the combination of the first periodic grating and the corresponding second periodic grating is called a composite grating; both the first periodic grating and the second periodic grating include a substrate and a plurality of microstructural units arranged periodically in one-dimensional or two-dimensional directions, and the microstructural units of the first periodic grating and the microstructural units of the second periodic grating are alternately arranged on the projection plane of the substrate, so that the imaging light rays and the infrared light rays pass through the first periodic grating and the second periodic grating independently for coupling in or out on the same side and in the same area of the waveguide substrate.

2. The smart glasses according to claim 1, characterized in that, The microstructural units of the first periodic grating are called first microstructural units, the first periodic grating includes N first microstructural units, and the N first microstructural units are arranged in a transverse and / or longitudinal array; in the first periodic grating, the length of the center line connecting two adjacent first microstructural units in the transverse direction is the first transverse period length, and the length of the center line connecting two adjacent first microstructural units in the longitudinal direction is the first longitudinal period length; the included angle between the center line connecting two adjacent first microstructural units in the transverse direction and the center line connecting two adjacent first microstructural units in the longitudinal direction is the first periodic unit interior angle, and the first periodic unit interior angle is 90° to 150°; the microstructural units of the second periodic grating are called second microstructural units; the second periodic grating includes M second microstructural units; the M second microstructural units are arranged in a transverse and / or longitudinal array; in the second periodic grating, the length of the center line connecting two adjacent second microstructural units in the transverse direction is the second transverse period length, and the length of the center line connecting two adjacent second microstructural units in the longitudinal direction is the second longitudinal period length; the included angle between the center line connecting two adjacent second microstructural units in the transverse direction and the center line connecting two adjacent second microstructural units in the longitudinal direction is the second periodic unit interior angle, and the second periodic unit interior angle is 90° to 150°; In the composite grating, the substrates of the overlapping portions of the first periodic grating and the second periodic grating share a common substrate.

3. The smart glasses according to claim 2, characterized in that, In the composite grating, the first microstructure units of the first periodic grating and the second microstructure units of the second periodic grating are arranged alternately with gaps on the projection plane of the substrate. Alternatively, the first microstructure units and the second microstructure units are arranged alternately on the projection plane of the substrate, and in the height direction of the substrate, at least some of the first microstructure units are height-overlapped with the corresponding second microstructure units.

4. The smart glasses according to claim 3, characterized in that, The total height H(x) of the microstructure units at position x in the composite grating satisfies the shape condition constraint of Formula 1 as follows: H(x) = G1(x) + G2(x) Wherein, G1(x) represents the height of the first microstructure unit at x; G2(x) represents the height of the second microstructure unit at x; and G1(x) and G2(x) respectively satisfy the following Formula 2 and Formula 3: Wherein, in Formula 2, h1 represents the height of the first microstructure unit, x1 represents the lateral offset distance of the first microstructure unit, and P1 represents the period of the first periodic grating; in Formula 3, h2 represents the height of the second microstructure unit, x2 represents the lateral offset distance of the second microstructure unit, and P2 represents the period of the second periodic grating. And in the composite grating, the diffraction angle of the imaging light is greater than the total reflection critical angle of the optical wave matrix, and the incident angle of the infrared light is greater than the total reflection critical angle of the optical wave matrix; both the first periodic grating and the second periodic grating satisfy the following Formula 4: P(sini ± sin0) = mλ Wherein, in Formula 4, P represents the grating period, i represents the incident angle of the corresponding light; ± represents different diffraction spectrum types, taking the positive sign when the incident light and the diffracted light are on the same side of the normal of the corresponding grating, and taking the negative sign when they are on the opposite side; θ represents the diffraction angle of the corresponding light, m represents the diffraction order, and λ represents the incident light wavelength of the corresponding light.

5. The smart glasses according to claim 2, characterized in that, The first lateral period length is 150 nm to 2 μm, and the first longitudinal period length is 150 nm to 2 μm.

6. The smart glasses according to claim 2, characterized in that, The side length of the first microstructure unit is 150 nm to 2 μm, and the height is 10 nm to 2 μm.

7. The smart glasses according to claim 2, characterized in that, The second lateral period length, the second longitudinal period length, and the inner angle of the second periodic unit of the second periodic grating are the same as the first lateral period length, the first longitudinal period length, and the inner angle of the first periodic unit, respectively.

8. The smart glasses according to claim 1, characterized in that, The thickness of the first periodic grating and the second periodic grating is 10 nm to 2 μm.

9. The smart glasses according to any one of claims 1 to 8, characterized in that, The first coupling-in and coupling-out grating group includes a first coupling-in grating and a first coupling-out grating located on the same side of the waveguide matrix; the second coupling-in and coupling-out grating group includes a second coupling-in grating and a second coupling-out grating, and the eye movement tracking optical group includes a light source and a pupil imaging device, and the light source is used to emit infrared light to the eye. The second coupling-in grating is used to couple the infrared light reflected from the eye into the waveguide matrix for transmission, and the second coupling-out grating is used to couple out the infrared light transmitted by the waveguide matrix from the optical wave matrix; the pupil imaging device is used to receive the infrared light with pupil information emitted from the optical wave matrix.

10. The smart glasses according to claim 9, characterized in that, The second input grating and the first output grating are located directly in front of the eye; the second input grating and the first output grating are non-coplanar, and the second output grating and the first input grating are coplanar and at least partially overlap; Alternatively, the second input grating and the first output grating are coplanar and at least partially overlap, and the second output grating and the first input grating are coplanar or non-coplanar.

11. The smart glasses according to claim 10, characterized in that, The second input grating and the first output grating are coplanar and completely overlap, and the second output grating and the first input grating are coplanar and at least partially overlap.

12. The smart glasses according to claim 10, characterized in that, The light source directly emits the infrared light towards the eye; or, the second input / output grating group further includes a third input grating and a third output grating disposed on the waveguide substrate, and the third input grating is located on the same side or the opposite side of the first input grating; the third output grating is located on the same side or the opposite side of the first output grating; The third input grating is configured to couple the infrared light emitted by the light source into the waveguide substrate; the third output grating is configured to couple out the infrared light transmitted by the waveguide substrate to enter the eye.

13. The smart glasses according to claim 12, characterized in that, The imaging optical group includes an image source and an image imaging unit, and the image imaging unit is configured to image the imaging light emitted by the image source and cause the imaged imaging light to reach the first input grating; The image imaging unit includes an image lens, and the image lens is disposed on the light-emitting side of the image source; Alternatively, the image imaging unit includes at least one metasurface lens, and the metasurface lens is disposed on the light-emitting side of the image source.

14. The smart glasses according to claim 13, characterized in that, The pupil imaging device includes a pupil camera, and the pupil camera is arranged side by side with the imaging optical group; Alternatively, the pupil imaging device includes a dichroic mirror and a pupil photosensitive element, and the imaging light emitted by the image source is linearly transmitted through the dichroic mirror and enters the image imaging unit; The infrared light is coupled out of the waveguide substrate by the second output grating and then sequentially enters the image imaging unit and the dichroic mirror, and reaches the pupil photosensitive element after being reflected by the dichroic mirror.

15. The smart glasses according to any one of claims 9 to 14, characterized in that, The waveguide substrate is a single-layer wave plate; or, the waveguide substrate is a multi-layer wave plate, and the first input / output grating group is located between two adjacent waveguide substrates.

16. The smart glasses according to claim 15, characterized in that, When the waveguide substrate is a multi-layer wave plate, the waveguide substrate includes a first-layer waveguide and a second-layer waveguide stacked on the first-layer waveguide, and the first input grating and the first output grating are disposed on the surface of the first-layer waveguide facing the second-layer waveguide; the second input grating and the first output grating are coplanar and at least partially overlap, and / or, the second output grating and the first input grating are coplanar and at least partially overlap.

17. The smart glasses according to claim 1, characterized in that The thickness of the waveguide substrate is 0.2 mm to 10 mm.

18. The smart glasses according to claim 1, characterized in that, The smart glasses further include temple arms, and the temple arms are connected to the eye socket through the connecting portion; Alternatively, the smart glasses further include a strap that can be tied to the head, and one end of the strap is connected to one connecting portion of the frame, and the other end is connected to the other connecting portion of the frame.

19. The smart glasses according to claim 18, wherein The temple and the connecting part are integrally formed; or, the temple and the connecting part are pivotally connected.

Images