Method for manufacturing an optical element, optical element and device for manufacturing an optical element
By controlling the characteristic local thickness of high-refractive-index solid materials and utilizing the perforated structure of the plate and non-zero distance deposition technology, the problem of scattering intensity modulation in the arrangement of diffraction gratings for AR glasses was solved, simplifying the manufacturing process and improving image quality and power efficiency.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- DISPELIX OY
- Filing Date
- 2021-06-09
- Publication Date
- 2026-07-14
AI Technical Summary
In existing technologies, it is difficult to achieve a scattering intensity modulation of 10 times or more when arranging diffraction gratings in AR glasses, which leads to complex manufacturing and increased costs, requiring additional process steps such as additional layer deposition and multiple etching.
By controlling the characteristic local thickness of high-refractive-index solid materials, and utilizing the perforated structure of the plate and non-zero distance deposition technology, a high degree of modulation of the diffraction grating can be achieved, avoiding additional deposition and etching steps.
It improves the scattering intensity modulation capability of diffraction gratings, simplifies the manufacturing process, reduces manufacturing costs, and improves image quality and power efficiency.
Smart Images
Figure CN115698779B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to a method for manufacturing optical elements, optical elements, and apparatus for manufacturing optical elements. Background Technology
[0002] The optical combiner of augmented reality (AR) glasses based on diffraction gratings is typically fabricated using a high-refractive-index film deposited on top of a transparent substrate that serves as a light guide and patterned to form a diffractive optical element (DOE).
[0003] The operation of the glasses means that light in the visible range is coupled into the waveguide through a diffraction grating, and after the light is distributed within the waveguide, it is coupled out through another diffraction grating, allowing the user to see a digital image in addition to the surrounding environment that can be seen through the waveguide. To achieve better image quality, the scattering intensity of the diffraction grating arrangement should typically be modulated in a controllable manner between low and high values, with large differences in scattering intensity across the diffraction grating arrangement, for example, 2 to 10 times or more.
[0004] Standard methods exist for modulating the scattering intensity on a diffraction grating arrangement, including variations in the grating pattern itself or variations in the height of the grating features (i.e., grating ridge height or grating groove depth). Variations in the grating pattern are inherently limited by the fabrication process employed, and typically cannot provide sufficiently strong modulation of scattering intensity on a diffraction grating arrangement (e.g., 10 times or more). Therefore, in many cases, controllable variations in the height of the grating features are required. However, this type of modulation complicates the fabrication of the diffraction grating arrangement and requires additional process steps, such as the deposition of additional layers, the introduction of multiple etching steps, and the use of grayscale lithography. Moreover, this complex fabrication sequence results in reduced process yield and increased manufacturing costs. Therefore, there is a fundamental need for improvement. Summary of the Invention
[0005] The present invention aims to provide improvements in the manufacturability of AR glasses.
[0006] This invention is defined by the independent claims. Embodiments are defined in the dependent claims. Attached Figure Description
[0007] Exemplary embodiments of the present invention are described below by way of example only, with reference to the accompanying drawings, wherein...
[0008] Figure 1A and 1B An example of AR glasses is shown;
[0009] Figure 2 An example of a deposition process is shown;
[0010] Figure 3AAn example of a perforated plate is shown;
[0011] Figure 3B An example is shown of a solid material layer deposited onto a waveguide through a perforated plate;
[0012] Figure 3C Examples of patterned resist or etch mask on a layer are shown;
[0013] Figure 4 An example showing the height distribution of the ridges of a diffraction grating, the ridges being made of solid material on a waveguide;
[0014] Figure 5A Examples are shown of the height distribution of ridges made of solid material and the cross-sectional area of perforations in a plate;
[0015] Figure 5B Another example showing the height distribution of the ridge and the cross-sectional area of the perforations in the plate;
[0016] Figure 6 An example of a bent plate is shown;
[0017] Figure 7 Examples of DOEs including waveguides with diffraction gratings are shown; and
[0018] Figure 8 An example of a flowchart illustrating a manufacturing method. Detailed Implementation
[0019] The following embodiments are merely examples. While the specification may refer to "one" embodiment in several places, this does not necessarily mean that every such reference refers to the same embodiment, or that the feature applies only to a single embodiment. Individual features of different embodiments may also be combined to provide other embodiments. Furthermore, the words "comprising" and "including" should be understood not to limit the described embodiments to consisting only of those features already mentioned, and such embodiments may also include features / structures not specifically mentioned. All combinations of embodiments are considered possible if they do not result in structural or logical contradictions.
[0020] It should be noted that although the accompanying drawings illustrate various embodiments, they are simplified diagrams showing only some structural and / or functional entities. Connections shown in the drawings may refer to logical or physical connections. It will be apparent to those skilled in the art that the described apparatus may also include other functions and structures besides those described in the drawings and text. It should be understood that details of some functions, structures, and signaling for operation are not relevant to the actual invention. Therefore, they do not need to be discussed in more detail here.
[0021] Below, a technique is proposed for controlling the local thickness of features of a diffraction grating made of a solid material with a high refractive index. Periodic features can include ridges and grooves of the diffraction grating, such as grooves located between any two directly adjacent ridges, and vice versa. The thickness can be controlled in one or two dimensions. A fundamental benefit of this method is that the thickness profile of the features of the solid material with the high refractive index can be custom-shaped. The formed profile is then used to fabricate a DOE with scattering efficiency modulation that follows the thickness profile of the deposited film. For example, unlike methods with multiple etching steps, a DOE can be formed with only a single etching step.
[0022] Figure 1A and 1B An example of AR (Augmented Reality) glasses is shown. For example, the glasses can look like glasses, spectacles, or goggles. In one implementation, the glasses can be attached to a headgear such as a cap, hat, or helmet. Figure 1A In this design, the glasses include an optical element 10 and an image generation unit 12. The image generation unit 12 may further include an image source 14 and an optical component arrangement 16. The image generation unit 12 generates visible light for an image (static or video), which is coupled to a visible light waveguide 106 via the optical component arrangement 16 and a diffraction grating 102 located on the surface of the waveguide 106. Figure 1B In this design, the eye comprises two parts, A and B, each for one eye 150, 152. The image generation unit 12 can guide the visible light of the image to the optical component device 16, which can separate the light from the two parts A and B. Alternatively, the glasses can have two image generation units 12, each for one part A and one part B.
[0023] Waveguide 106 allows visible light to propagate from the coupled region to one or more desired regions via total internal reflection, wherein the visible light is coupled into waveguide 106 through diffraction grating 102, and the one or more desired regions have a first coupled-out diffraction element 100 and a second coupled-out diffraction grating 104. For example, waveguide 106 may be made of a transparent material such as glass, sapphire, and / or polymers. For example, glass may include a family of high-refractive-index flint glasses. Waveguide 106 may also be referred to as a light guide. The refractive index of waveguide 106 may be from about 1.7 to 2 or higher.
[0024] Visible light is thus laterally guided within the waveguide 106, and one or both of the first and second coupled-out diffraction gratings 100 and 104 couple the visible light to the waveguide 106 to direct the visible light to one or both of the user's eyes 150, 152 for image display. The coupled-out diffraction gratings 100 and 104 serve as optical combiners in the AR glasses. That is, the user can see the environment through the optical components 10 and the image scattered from the first and second diffraction gratings 100 and 104.
[0025] In one embodiment, the distance DD between the first outgoing diffraction grating 100 and the second outgoing diffraction grating 104 can be at least approximately equal to the distance DE between human eyes 150 and 152, which is referred to as the interpupillary distance (IPD). The distance DD can be, for example, about 63 mm. However, in another embodiment, the first outgoing diffraction grating 100, the incoming diffraction grating 102, and the second outgoing diffraction grating 104 can be formed as a continuous diffraction element structure on the waveguide 106.
[0026] As a further detail, for example, the distance DD can be the same as the average or estimated value of IPD. For example, IPD, i.e., distance DE, can be approximately 64 mm for males and approximately 62 mm for females. Therefore, the distance DD can be determined as the interval between the center of the first coupling diffraction grating 100 and the center of the second coupling diffraction grating 104.
[0027] exist Figure 1A In the embodiment shown in the figure, the glasses have an optical component 10 for the eyes 150, 152 and an image generation unit 12.
[0028] In one embodiment, the glasses may have an optical component 10 and an image generation unit 12 for each eye 150, 152.
[0029] In one embodiment, diffraction gratings 100 to 104 may be on either side of waveguide 106. In another embodiment, at least one of diffraction gratings 100 to 104 may be on the side of waveguide 106 opposite to at least one of them.
[0030] Figure 2An example of a deposition process is shown. Material 200 for forming at least one diffraction grating 100, 102, 104 is deposited through perforations 204 of plate 202 onto waveguide 106 or a preform of waveguide 106. During manufacturing, the term "waveguide" is also considered to include the preform of waveguide 106. Plate 202 is located at a non-zero distance D from waveguide 106. For example, spacer structure 206 can be used to set the distance D. Plate 202 can be supported by spacer structure 206. If the waveguide 106 is circular, spacer structure 206 can be a ring surrounding the outer contour of waveguide 106. The total thickness of the structure including spacer structure 206 can be greater than the thickness at distance D. Spacer structure 206 can be a shape with a circular outer circumference and an inner side having circular openings, rectangular openings, and / or other custom-shaped openings that support positioning the plate above waveguide 106 and mask other areas to prevent material 200 deposition thereon. Therefore, the spacer structure 206 can have a thickness equal to the distance D. The material of the spacer structure 206 may include, for example, metal, glass, ceramic, etc. In one embodiment, the spacer structure 206 may include, for example, anodized aluminum.
[0031] In one embodiment, the spacer structure 206 may include at least one adjusting device 210. For example, the adjusting device 210 may be mechanical, electromechanical, hydraulic, and / or pneumatic. A mechanical adjusting device may, for example, include a screw. An electromechanical adjusting device may, for example, include an electric motor and a screw rotated by the electric motor.
[0032] Distance D is an important parameter that can be considered based on factors such as: a) the type of deposition reactor, the nature and parameters of the deposition process; b) the thickness of plate 202; c) the characteristic dimensions of the structure including the height and / or width of the perforations 204 and the perforations 204 in plate 202; d) the specific DOE layout; and e) the arrangement of the DOEs on the wafer. Here, DOE layout means that different grating shapes are possible and depend on specific shapes (e.g., rectangular, bow-shaped, triangular, etc.). The perforations 204 in plate 202 will have different arrangements. The arrangement of the DOEs means that different options exist, depending on how several DOEs with varying heights are positioned relative to each other to adjust or control the height profile of layer 300.
[0033] The distance D between plate 202 and waveguide 106 can be set to a specific optimal value. In one embodiment, distance D may be, for example, about 5 mm. If distance D is too small, the features of perforation 204 may not be sufficiently defined, and the structure of layer 300 may not be sufficiently conformable. If distance D is too long, the accuracy of local film thickness control may be reduced. In one embodiment, plate 202 may be tilted relative to waveguide 106.
[0034] In one embodiment, the spacer structure 206 may also include additional elements, which are not shown in the figures, for specific purposes. These elements may be: a) additional features supporting the shadow mask, b) additional features for screening areas (or around) the manufactured DOE, where high-refractive-index materials should not be deposited, i.e., areas that should remain clean away from the deposited high-refractive-index layer.
[0035] The material of plate 202 may include, for example, metal, glass, ceramic, etc. In one embodiment, the metal may be, for example, high-purity stainless steel. In one embodiment, the thickness of plate 202 may be, for example, between about 0.001 mm and about 1 mm. In one embodiment, a typical thickness may be, for example, between about 0.01 mm and about 0.1 mm. In one example, the thickness may be about 0.05 mm.
[0036] In one embodiment, the diameters of the waveguide 106 and plate 202 can vary from tens of millimeters to 450 mm, for example. The large waveguide 106 can be cut into a piece suitable for eyeglasses. In one embodiment, the diameters of the waveguide 106 and plate 202 can be, for example, about 100 mm. The deposition system 208 can be scaled / modified or scalable for waveguides 106 with smaller / larger diameters.
[0037] like Figure 3A As shown in the example, it illustrates Figure 2 The cross-sectional area of the perforation 204, E, varies in a determined manner depending on its position in the plate 202. Figure 3A Only a few perforations have reference numbers (because it's impossible to number all perforations). Figure 3A In the example, the cross-sectional area of the perforation 204 varies in the X-axis direction but remains constant in the Y-axis direction.
[0038] In one embodiment, the variation of the cross-sectional area of the perforation 204 on the surface of the plate 202 can be one-dimensional, while the cross-sectional area of the perforation 204 can remain constant in another dimension (the perforations can be distributed only in two-dimensional space). Each dimension can be considered as a spatial extent orthogonal to and / or independent of the other dimension, and can be a dimension of a Cartesian coordinate system or a polar coordinate system. In one embodiment, the cross-sectional area of the perforation 204 can vary as a function of the values of the two dimensions.
[0039] Figure 3A A hexagonal perforation is shown as an example, with the mask opening area modulated in the X direction. For example, the shape of the perforation 204 can be: hexagonal, circular, rectangular, linear, star-shaped, or any combination thereof. The shape of the perforation 204 can also be customized.
[0040] A plate 202 with perforations 204 can be manufactured to satisfy the desired ratio of opening to solid area or grating fill factor in the x direction, in the x and y directions, or in a custom pattern on the plate 202.
[0041] In one embodiment, the solid material 200 can be rendered into a flowable state, which may be gaseous or vaporous, to allow it to pass through the perforations 204 of the plate 202. The flowable material 200 is then cured on the waveguide 106.
[0042] In one embodiment, material transfer for deposition onto the waveguide can be performed, for example, in an evaporating state. Then, for example, in a vapor deposition process, the solid material 200 can be converted into a vapor state and the vapor condenses on the waveguide 106 as a layered or film structure. Vapor deposition can be achieved, for example, using sputtering, chemical vapor deposition, or physical vapor deposition, but is not limited to these.
[0043] Those skilled in the art are familiar with various deposition systems and processes that can be used as deposition system 208. Solid material 200 may, for example, have a refractive index equal to or higher than that of waveguide 106 in the visible light range. In some cases, the refractive index of material 200 may also be lower than that of waveguide 106. For example, the refractive index of solid material 200 may be in the range of about 1.8 to about 2.7 or even up to 3.5. However, it may also be lower than about 1.8. A high refractive index results in efficient light scattering and generally better DOE performance over a wide range of insertion and exit angles, which in turn leads to better image quality for the user.
[0044] Figure 3B This illustrates an example of how the perforated pattern of plate 202 can be transformed into a specific height profile of layer 300 of material 200 on waveguide 106. In this example, the distribution of material 200 can be linear, or it can follow any shape, such as the shape of a nonlinear function.
[0045] The unit cells of the features in board 202 should be small enough to provide high control over the local thickness of layer 300 and good uniformity. Since the minimum feature size is limited by other factors, such as the thickness of board 202 and the perforation technique, thin masks such as 0.1 mm and below are generally advantageous. The required resolution of the features in board 202 and the thickness of board 202 depend on the specific layout of the DOE being manufactured.
[0046] In one embodiment, the distance D between plate 202 and waveguide 106 may depend on the cross-sectional area of the perforation 204 in plate 202. In another embodiment, the distance D between plate 202 and waveguide 106 may depend on the minimum cross-sectional area of the perforation 204 in plate 202.
[0047] In one embodiment, the smaller the cross-sectional area of the perforation 204 of plate 202, the shorter the distance D. Correspondingly, the larger the cross-sectional area of the perforation 204 of plate 202, the longer the distance D. In this way, material 200 can also extend to areas of waveguide 106 that do not directly overlap with or face the perforation 204. Such extension, in turn, results in a flat or at least reasonably flat layer 300 of material 200 on waveguide 106.
[0048] Figure 3C An example of a patterned resist or etch mask layer 302 on layer 300 of material 200 is shown. Layer 300 of material 200 can then be etched to form features including ridges 304 and grooves 306 of a grating (see [link]). Figure 4 In one embodiment, etching may include dry etching. Instead of etching, the features of the diffraction grating (100 to 104) may be formed by, for example, any other suitable prior art patterning method.
[0049] like Figure 4 As shown in the example, at least one diffraction grating 100 to 104 is thus made of a layer 300 of solid material 200, which is transferred to the waveguide 106 in the deposition system 208. A material removal device, which may include an etching apparatus or any other suitable prior art material removal device as explained above, can remove the solid material 200 of the layer 300 from the location of the groove 306 of at least one diffraction grating 100 to 104 and retain the solid material 200 of the layer 300 at the location of the ridge 304 of at least one diffraction grating 100 to 104. The horizontal axis X represents position in one direction, while the vertical axis represents height H. Both axes are arbitrary scales.
[0050] The amount of solid material 200 in each ridge 304 of the gratings 100 to 104 on the waveguide 106 varies in response to the cross-sectional area of the perforation 204. Therefore, the height of each ridge 304 made of solid material 200 on the waveguide 106 varies in response to the cross-sectional area of the perforation 204. Since the cross-sectional area of the perforation 204 varies with position, the height of the ridge 304 also varies with position on the plate 202. The larger the cross-sectional area of the perforation, the greater the thickness of the solid material 200 ridge 304 at the corresponding position on the waveguide 106. Different solid materials 200 can be deposited to different heights with the same perforation cross-sectional area, but those skilled in the art can readily find suitable cross-sectional areas for the desired solid material.
[0051] The grating period of the diffraction gratings 100 to 104, i.e., the distance between the ridges 304 and / or the grooves 306, can be, for example, from about 200 nm to about 500 nm. The height of the ridges 304 of the diffraction gratings 100 to 104 can vary, for example, from about 10 nm to about 300 nm, and in some cases, from about 10 nm to about 1000 nm.
[0052] The non-zero distance D between plate 202 and waveguide 106 causes the flowable state of solid material 200 to be distributed over a region with a cross-sectional area larger than that of the perforation 204 in waveguide 106 (see [link]). Figure 3B That is, solid material 200 is also deposited next to the perforation 204 below plate 202. This leakage is generally considered undesirable, but for DOE, leakage is advantageous because it allows for the formation of the desired thickness profiles of layer 300 of solid material 200 and diffraction gratings 100, 102, 104. Due to the leakage, the height of layer 300 facing the perforation 204 and the height of the solid surface of layer 300 facing plate 202 have negligible or no difference. That is, layer 300 can be made very smooth so that it does not expose the location of the perforation 204 in plate 202. For example, the profile of layer 300 can be customized to have multiple higher and lower thickness regions.
[0053] The shape of the thickness profile can also be altered by changing the distance D between the waveguide 106 and the plate 202. In one embodiment, the distance D can vary at opposite ends of the plate 202 / waveguide 106. The height profile will then follow more perforation features on the side with the smaller distance, and the height profile will be more uniform on the side with the larger distance.
[0054] Figure 5A Showing based on Figures 3A to 4 Examples include the distribution 400 of the height of layer 300 and the corresponding ridge 304 of the diffraction grating on waveguide 106, and the distribution 402 of the cross-sectional area of the perforation 204 in plate 202 along the X-axis. In these examples, distributions 400 and 402 are linear. The Z-axis on the left represents the height H, the right side represents the region A, and the X-axis represents the position (= distance from the origin). All axes are arbitrary scales.
[0055] Figure 5B Examples of the height of layer 300 and the distribution 400 of ridges 304, such as on waveguide 106, are shown, as well as an example of the distribution 402 of the cross-sectional area of perforations 204 in plate 202 in the X-axis direction. In this example, the distributions are dissimilar, although they could be similar. Figure 5BThe results can be based on the characteristic that perforations 204 are larger in the middle but have lower density. In this example, distributions 400 and 402 resemble bell curves. The left Z-axis represents height H, the right side represents region A, and the X-axis represents location (= distance from the origin). All axes are arbitrary scales.
[0056] exist Figure 6 In the embodiments and examples shown, plate 202 may be curved, i.e., the longitudinal profile of plate 202 may be curved, for example, wavy. In one embodiment, plate 202 may be curved in only one dimension. In one embodiment, plate 202 may be curved in two dimensions. In one embodiment, the curvature of plate 202 may be similar in both dimensions. In one embodiment, the curvature of plate 202 may be different in both dimensions. In these ways, leakage can be generated in a controlled and desired manner below plate 202 adjacent to perforation 204 at different locations on plate 202 / waveguide 106. The curvature can be combined with variations in the cross-sectional area of perforation 204 of plate 202, allowing for controlled variations in the height of layer 300.
[0057] In one embodiment, an anti-reflective coating may be applied to the diffraction gratings 100 to 104.
[0058] like Figure 4 As shown in Figure 5, in one embodiment, diffraction gratings 100, 102, and 104 can be fabricated, which simultaneously satisfy the following three definitions:
[0059] 1) There exist multiple pairs of directly continuous ridges 304 that satisfy the following characteristics;
[0060] 2) There is no solid material 200 between any pair of said pairs, and there is no solid material 200 between the ridges 304 of any pair of said pairs; and
[0061] 3) Any pair of ridges 304 have different heights in the direction in which the height of ridge 304 increases or decreases.
[0062] For example, in Figure 5B At the top of the bell-shaped curve of the distribution 400, there may be a pair of ridges 304 that are directly adjacent to each other and have the same height. However, in one embodiment, the distribution may be made such that there is no pair of ridges 304 that are directly adjacent to each other and have the same height on the rising portion of the distribution 400. In one embodiment, this can also be done for the falling portion of the distribution 400.
[0063] The lateral dimension of a DOE can be, for example, from about 10 mm to about 20 mm, and the period of the diffraction grating can be, for example, about 400 nm, wherein the grating height of the diffraction grating increases / decreases linearly, for example, from about 0 nm to about 50 nm.
[0064] Solid material 200 may be a compound of at least two elements. In one embodiment, the solid material may be, for example, titanium oxide (TiO2). Titanium oxide may be amorphous. The refractive index of titanium oxide may be about 2.4 at wavelengths in the visible light range. Depending on the specific type and application of the DOE, material 200 should be sufficiently optically transparent to visible light passing through the thickness of layer 300.
[0065] Figure 7 It is shown that the coupled-in diffraction grating 102 can have a ridge 304 with a constant height, while the coupled-out diffraction grating 100 can have a ridge 304 with a varying height.
[0066] In an alternative embodiment, it is also possible that the output diffraction grating 100 may have a ridge 304 with varying height, and the input diffraction grating 102 may have a ridge 304 with constant height. Furthermore, in one embodiment, both the output diffraction grating 100 and the input diffraction grating 102 may have ridges 304 with varying height.
[0067] In one embodiment, the output diffraction grating 100 and the input diffraction grating 102 may have different variations in the height of the ridge 304.
[0068] In one embodiment, the height variation of the ridge 304 of the coupled-out diffraction grating 100 and the height variation of the ridge 304 of the coupled-in diffraction grating 102 can have mirror symmetry.
[0069] In one embodiment, the output diffraction grating 100 and the input diffraction grating 102 may have similar variations in the height of the ridge 304.
[0070] Appropriate combinations of similar or different height distributions among different diffraction gratings 100, 102, and 104 (where such combination may depend on the application) can improve the quality of the images transmitted from the image generation unit 12 to the user's eyes 150 and 152, thereby allowing for better image uniformity, better color distribution, and / or deeper contrast. In these ways, the overall user experience can be improved. The possibility of increased brightness allows the glasses to be used in different environments, such as under bright outdoor lighting conditions. Additionally, when the glasses device has high optical efficiency, it consumes less power, thus saving battery power and / or allowing for longer operating time.
[0071] As described above, the deposition method includes a plate 202 having perforations 204, and a non-zero distance between the plate 202 and the waveguide 106. This non-zero distance can be achieved using a spacer structure 206. Material 200 penetrates the perforations 204 in a gaseous state at a rate that depends on the measurable size of the cross-sectional area of the perforations 204 at each location. The plate 202 is held at a specific distance from the waveguide 106 to achieve desired thickness modulation on the waveguide 106, and similarly maintains the conformality of the layers 300 and the ridges 304.
[0072] The above-described method directly addresses the problem of scattering efficiency modulation in DOEs, offering at least two significant advantages over commonly used methods. First, it improves the performance of DOEs with highly variable grating features. This is because the controllable variation of the grating height leads to enhanced modulation of the DOE's scattering intensity, which cannot be achieved solely through in-plane variations of the grating pattern. Second, the manufacturability of this DOE component is significantly superior to one of the widely used alternative methods. In particular, the proposed solution allows for the avoidance of additional deposition steps, additional etching steps, additional photolithography steps, and the use of grayscale lithography when fabricating DOEs with highly variable periodic features.
[0073] Figure 8 This is a flowchart of a method for manufacturing an optical element 10 for augmented reality glasses. The optical element 10 includes a waveguide 106 for visible light and a combination of at least one diffraction grating 100, 102, 104 configured to couple visible light between the waveguide 106 and the environment. In step 800, at least one layer 300 of solid material 200 at a non-zero distance D from the waveguide 106 is deposited on the waveguide 106 through a perforation 204 in plate 202. In step 802, the height of the at least one layer 300 is varied in response to the cross-sectional area of the perforation 204, which varies based on the position of the perforation 204 in plate 202, to form at least one diffraction grating 100, 102, 104 on the waveguide 106 from the at least one layer 300. The at least one diffraction grating 100, 102, 104 is configured to perform visible light coupling into and / or out of the waveguide 106 and the environment.
[0074] In step 804, which is performed optionally, the ridges 304 of at least one diffraction grating 100, 102, 104 are formed by removing solid material 200 from the waveguide 106 at the location of the periodic grooves 306 between the ridges 304.
[0075] It will be apparent to those skilled in the art that the inventive concept can be implemented in various ways with advancements in technology. The present invention and its embodiments are not limited to the exemplary embodiments described above, but can be varied within the scope of the claims.
Claims
1. A method for manufacturing an optical element (10) for augmented reality glasses, characterized in that, On the waveguide (106), at least one layer (300) of material (200) is deposited (800) at a non-zero distance (D) from the waveguide (106) through a perforation (204) of a bent plate (202). as well as The height of the at least one layer (300) is manufactured (802) to vary in response to the cross-sectional area of the perforation (204), the cross-sectional area of the perforation (204) being configured to vary based on the position of the perforation (204) in the plate (202), such that at least one diffraction grating (100, 102, 104) is formed on the waveguide (106) from the at least one layer (300), the at least one diffraction grating (100, 102, 104) being configured to perform visible light coupling in and / or coupling out between the waveguide (106) and the environment; The curvature of the curved plate (202) is combined with the change in the cross-sectional area of each perforation (204) on the curved plate (202) to control the height change of the layer (300) in a desired manner.
2. The manufacturing method according to claim 1, characterized in that, Change the non-zero distance (D) between the plate (202) and the waveguide (106).
3. The manufacturing method according to claim 1, characterized in that, The material (200) has a refractive index in the visible light range that is equal to or higher than that of the waveguide (106).
4. The manufacturing method according to claim 1, characterized in that, Deposition is performed by at least one of sputtering, chemical vapor deposition, and physical vapor deposition.
5. The manufacturing method according to claim 1, characterized in that, The ridges (304) of the at least one diffraction grating (100, 102, 104) are formed (804) by removing the material (200) from the at least one layer (300) at the location of the groove (306) between the ridges (304).
6. The manufacturing method according to claim 1, characterized in that, The plate (202) is tilted relative to the waveguide (106).
7. The manufacturing method according to claim 1, characterized in that, The refractive index of the material is higher than 1.
8.
8. The manufacturing method according to claim 1, characterized in that, The cross-sectional area of the perforation (204) is configured to vary in two dimensions, so that the height of the deposition (300) varies in the two dimensions.
9. An optical component (10), characterized in that, The optical component (10) includes at least one diffraction grating (100 to 104) manufactured by the manufacturing method of claim 1.
10. An apparatus for manufacturing an optical component (10), characterized in that, The device includes a plate (202) with perforations (204), each perforation (204) having a cross-sectional area depending on its position on the plate (202), the plate (202) and the waveguide (106) of the optical component (10) being configured to have a non-zero distance therebetween; and The device is configured to deposit at least one layer (300) of material (200) on the waveguide (106) through the perforation (204) of the plate (202) such that the height of the layer (300) on the waveguide (106) varies in response to the cross-sectional area of the perforation (204); The plate (202) is bent relative to the waveguide (106); The curvature of the plate (202) is combined with the change in the cross-sectional area of each perforation (204) on the plate (202) to control the height change of the layer (300) in a desired manner.
11. The apparatus according to claim 10, characterized in that, The device is configured to allow the distance (D) between the plate (202) and the waveguide (106) to vary.
12. The apparatus according to claim 10, characterized in that, The device has an adjustment device (210) configured to adjust the distance (D) between the plate (202) and the waveguide (106) based on the cross-sectional area of the perforation (204).
13. The apparatus according to claim 10, characterized in that, The device is configured to remove the material (200) from the position of the gap (306) between the ridges (304) of the at least one diffraction grating (100, 102, 104) and hold the material (200) at the position of the ridge (304) of the at least one diffraction grating (100, 102, 104).