Preparation method of optical waveguide element and display equipment

Abstract

The invention discloses a preparation method of an optical waveguide element and display equipment. The method comprises the following steps: providing an optical waveguide substrate; shielding other areas except the coupling-out area on the optical waveguide substrate, and plating a first coating material on the coupling-out area to obtain a first intermediate element; plating a second coating material on the surface of the first intermediate element to obtain a second intermediate element; shielding other areas except the area where the coupling-out area is located on the surface of the second intermediate element, and spraying an etching material to a first unshielded area on the surface of the second intermediate element to remove the second coating material and the first coating material plated on the coupling-out area so as to obtain a third intermediate element; and shielding a grating region on the surface of the third intermediate element, and spraying an etching material to a second unshielded region on the surface of the third intermediate element so as to remove the second coating material in the second unshielded region, thereby obtaining the optical waveguide element, and realizing accurate selective coating of the coupling region of the optical waveguide. And therefore, the optical waveguide element can be accurately prepared.

Description

Technical Field

[0001] This application relates to the field of optical technology, and more specifically, to a method for fabricating an optical waveguide element and a display device. Background Technology

[0002] To further improve the diffraction efficiency of optical waveguides, coatings are typically applied to the coupling-in region, transition region, or coupling-out region of the optical waveguide. However, existing methods for fabricating optical waveguide components make it difficult to achieve precise selective coating on the optical waveguide to fabricate the components. Summary of the Invention

[0003] This application proposes a method for fabricating an optical waveguide element and a display device to improve the above-mentioned defects.

[0004] In a first aspect, embodiments of this application provide a method for fabricating an optical waveguide element. The method includes: providing an optical waveguide substrate, the surface of which is provided with an outgoing region and an incoming region; shielding other regions on the optical waveguide substrate except for the outgoing region, and depositing a first coating material on the outgoing region to obtain a first intermediate element; depositing a second coating material on the surface of the first intermediate element to obtain a second intermediate element; the refractive index of the second coating material is greater than the refractive index of the optical waveguide substrate; shielding other regions on the surface of the second intermediate element except for the region where the outgoing region is located, and spraying an etching material onto a first unshielded region on the surface of the second intermediate element to remove the second coating material and the first coating material deposited on the outgoing region, to obtain a third intermediate element; shielding a grating region on the surface of the third intermediate element, and spraying an etching material onto a second unshielded region on the surface of the third intermediate element to remove the second coating material in the second unshielded region, to obtain an optical waveguide element; the grating region includes at least the region where the outgoing region is located and the region where the incoming region is located.

[0005] Secondly, embodiments of this application provide a display device, including an optical waveguide element prepared according to the aforementioned method for preparing an optical waveguide element.

[0006] This application provides a method for fabricating an optical waveguide element and a display device. In this application, firstly, the surface of an optical waveguide substrate, excluding the coupling region, is shielded. A first coating material is then deposited onto the optical waveguide substrate, specifically onto the coupling region, to obtain a first intermediate element. Next, a second coating material is deposited onto the surface of the first intermediate element to obtain a second intermediate element. The refractive index of the second coating material is higher than that of the first coating material. Subsequently, the surface of the second intermediate element, excluding the coupling region, is shielded. Etching material is then sprayed onto the first unshielded area of ​​the second intermediate element to remove the first and second coating materials deposited on the unshielded coupling region, resulting in a third intermediate element. Finally, the surface is shielded again. The third intermediate element includes a grating region comprising the region where the coupling-out region is located and the region where the coupling-in region is located. Etching material is sprayed onto the second unshielded region on the third intermediate element to remove the second coating material on the unshielded region of the surface of the third intermediate element, thereby obtaining an optical waveguide element. Through the above process, it is ensured that both the first and second coating materials deposited on the coupling-out region are removed, and at least the region where the coupling-in region is located on the optical waveguide element is coated with the second coating material. By coating the coupling-in region with the second coating material, the diffraction efficiency of the optical waveguide substrate can be enhanced, and precise selective coating of the coupling-in region of the optical waveguide can be achieved. This avoids the problem of light leakage in the coupling-in region caused by coating the entire surface of the optical waveguide, thereby achieving precise fabrication of the optical waveguide element.

[0007] Other features and advantages of the embodiments of this application will be set forth in the following description, and will be apparent in part from the description, or may be learned by practicing the embodiments of this application. The objects and other advantages of the embodiments of this application may be realized and obtained by means of the structures particularly pointed out in the written description, claims, and drawings. Attached Figure Description

[0008] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0009] Figure 1 A flowchart of a method for fabricating an optical waveguide element according to an embodiment of this application is shown.

[0010] Figure 2 A flowchart of a method for fabricating an optical waveguide element according to another embodiment of this application is shown.

[0011] Figure 3 The diagram shows a surface, substrate, first solid plate, and first perforated plate of an optical waveguide substrate according to an embodiment of this application.

[0012] Figure 4 A flowchart illustrating step S102 according to an embodiment of this application is shown.

[0013] Figure 5 A flowchart illustrating step S104 according to an embodiment of this application is shown.

[0014] Figure 6 A flowchart illustrating step S105 according to an embodiment of this application is shown.

[0015] Figure 7 A flowchart illustrating a method for fabricating an optical waveguide element according to another embodiment of this application is shown.

[0016] Figure 8 A flowchart of a method for fabricating an optical waveguide element according to another embodiment of this application is shown.

[0017] Figure 9 This diagram illustrates the positional relationship between an optical waveguide substrate, at least one reference grating, and a motion platform according to an embodiment of this application.

[0018] Figure 10 A schematic diagram showing the positional relationship between the adjusted motion platform and the magnetron coating source in an embodiment of this application is shown.

[0019] Figure 11 A flowchart illustrating the steps preceding step S103 according to an embodiment of this application is shown.

[0020] Figure 12 A schematic diagram of the second surface of an optical waveguide substrate and a second perforated plate in an embodiment of this application is shown.

[0021] Figure 13 A flowchart illustrating a method for fabricating an optical waveguide element according to another embodiment of this application is shown.

[0022] Figure 14 A flowchart illustrating step S103 according to an embodiment of this application is shown. Detailed Implementation

[0023] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present application, and not all of them. The components of the embodiments of the present application described and shown in the accompanying drawings can generally be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely represents selected embodiments of the present application. All other embodiments obtained by those skilled in the art based on the embodiments of the present application without inventive effort are within the scope of protection of the present application.

[0024] In the following description, the terms "first," "second," etc., are used merely to distinguish similar objects and do not represent a specific ordering of objects. It is understood that "first" and "second" can be interchanged in a specific order or sequence where permissible, so that the embodiments of this application described herein can be implemented in an order other than that illustrated or described herein. In the following description, references to "some embodiments or some ways of embodiments" describe a subset of all possible embodiments; however, it is understood that "some embodiments" can be the same subset or different subsets of all possible embodiments and can be combined with each other without conflict.

[0025] Please see Figure 1 , Figure 1 This application provides a flowchart of a method for fabricating an optical waveguide element according to an embodiment of the present application. The method includes:

[0026] S101, Provides the optical waveguide substrate.

[0027] The surface of the optical waveguide substrate is provided with an exit region and an entry region. Both the entry and exit regions are provided with gratings. The grating in the entry region is used to couple light into the optical waveguide substrate and allow it to propagate inside the optical waveguide substrate; the grating in the exit region is used to couple light propagating to the exit region out of the optical waveguide substrate.

[0028] In some embodiments, in addition to the coupling-out region and coupling-in region, the surface of the optical waveguide substrate may also have a transition region, and the transition region is also provided with a grating. The grating in the transition region is used to guide the light propagating to the transition region to the coupling-out region.

[0029] S102. Shield the optical waveguide substrate from other areas except the coupling region, and deposit the first coating material in the coupling region to obtain the first intermediate element.

[0030] The first coating material can be a chemically stable material, meaning it will not chemically react with the grating in the coupling region. The first coating material can be a metallic material, such as aluminum, copper, gold, silver, or their alloys, or a non-metallic material, such as silicon dioxide, titanium dioxide, or silicon carbide. The coating thickness of the first coating material is 0.1 nm to 100 nm, further, it can be 1 nm to 100 nm, and preferably, it can be 10 nm to 100 nm.

[0031] By shielding the optical waveguide substrate from other areas except the coupling region, it is ensured that during the deposition of the first coating material, the optical waveguide substrate from other areas except the coupling region will not be coated with the first coating material, but only the coupling region will be coated with the first coating material.

[0032] In some embodiments, a first coating material can be deposited on the coupling region using magnetron sputtering to obtain a first intermediate element. After shielding other areas on the optical waveguide substrate except for the coupling region, the first coating material can be deposited on the optical waveguide substrate facing the coupling region along a direction perpendicular to the surface where the coupling region is located to obtain the first intermediate element.

[0033] S103. A second coating material is deposited on the surface of the first intermediate element to obtain the second intermediate element.

[0034] The refractive index of the second coating material is greater than that of the optical waveguide substrate. The higher the refractive index, the higher the diffraction efficiency of the light beam in the optical waveguide.

[0035] The second coating material is any one of zinc oxide, titanium oxide, and hafnium oxide, preferably titanium oxide. The coating thickness of the second coating material on the second intermediate element is 0.1 nm-100 nm, further, the coating thickness of the second coating material can be 1 nm-100 nm, preferably, the coating thickness of the second coating material can be 10 nm-100 nm.

[0036] In some embodiments, S103 includes: depositing a second coating material on the surface of a first intermediate element using an atomic layer deposition (ALD) apparatus to obtain a second intermediate element. Specifically, after placing the first intermediate element in the vacuum chamber of the ALD apparatus, reactive gases are alternately injected into the vacuum chamber, each time forming a monolayer encapsulating the first intermediate element. By controlling the number of cycles of reactive gas injection, a second coating material of a specified thickness is deposited on the surface of the first intermediate element. Precise thin film deposition using an ALD apparatus can form a high-quality functional layer. Furthermore, by depositing the second coating material layer by layer on the surface of the first intermediate element, the ALD apparatus can achieve sub-nanometer-level control over the film thickness.

[0037] In this process, the area where the coupling region is located on the surface of the second intermediate element is coated with a first coating material and a second coating material, while other areas except the coupling region are coated with only the second coating material.

[0038] S104. Cover the surface of the second intermediate element with the areas other than the area where the coupling region is located, and spray etching material onto the first uncovered area on the surface of the second intermediate element to remove the second coating material and the first coating material deposited on the coupling region, thereby obtaining the third intermediate element.

[0039] The first unmasked area on the surface of the second intermediate element refers to the area on the surface of the second intermediate element that was not masked in step S104, that is, the area on the surface of the second intermediate element where the coupling area is located.

[0040] The selection of the etching material must ensure that it can remove both the second and first coating materials. In some embodiments, the etching source can bombard the first unmasked area on the surface of the second intermediate element with the etching material in the form of a plasma beam. In this way, the second coating material in the first unmasked area can be removed first, and then the first coating material can be removed to obtain the third intermediate element.

[0041] By shielding the surface of the second intermediate element from other areas except the area where the coupling region is located, it is ensured that during the spraying of etching material onto the surface of the second intermediate element, the etching material will not reach other areas on the surface of the second intermediate element except the area where the coupling region is located, and will only reach the first unshielded area on the surface of the second intermediate element.

[0042] In some embodiments, the etching rate of the etching source can be set according to the thickness of the first coating material and the thickness of the second coating material in the first unshielded area on the surface of the second intermediate element, so as to ensure that the etching source is controlled to remove the first coating material and the second coating material deposited on the coupling region substantially completely by ion beam etching according to the set etching rate.

[0043] S105. The grating region on the surface of the third intermediate element is shielded, and etching material is sprayed onto the second unshielded region on the surface of the third intermediate element to remove the second coating material in the second unshielded region, thereby obtaining an optical waveguide element.

[0044] The grating region includes at least the region containing the coupling-out region and the region containing the coupling-in region. The second unmasked region on the surface of the third intermediate element refers to the region on the surface of the third intermediate element other than the masked grating region.

[0045] By using the grating area on the surface of the third intermediate element, it is ensured that during the spraying of etching material onto the surface of the third intermediate element, the etching material will not reach the grating area on the surface of the third intermediate element, but will only reach the second unmasked area on the surface of the third intermediate element.

[0046] After the above steps S102-S105, it can be seen that, compared with the optical waveguide substrate, the optical waveguide element is coated with a second coating material at least in the coupling region.

[0047] In some embodiments, if a transition region is provided on the optical waveguide substrate, the grating region in step S105 includes the region where the transition region is located. Correspondingly, in this case, the optical waveguide element is coated with a second coating material in the coupling region and the transition region, relative to the optical waveguide substrate.

[0048] In some embodiments, after S105, the method further includes: if a first coating material remains on the optical waveguide element, performing wet etching on the remaining first coating material on the optical waveguide element.

[0049] Wet etching can be achieved using an etching solution, which can be an acid, alkali, or salt solution, selected based on the material of the first coating. During wet etching, parameters such as the temperature, concentration, and etching time of the etching solution need to be controlled. In this embodiment, wet etching is performed on the residual first coating material on the optical waveguide element, avoiding over-etching on the surface of the resulting optical waveguide element.

[0050] In this application, firstly, the surface of the optical waveguide substrate, excluding the coupling region, is shielded. A first coating material is then deposited onto the optical waveguide substrate, specifically onto the coupling region, to obtain a first intermediate element. Next, a second coating material is deposited onto the surface of the first intermediate element to obtain a second intermediate element. The refractive index of the second coating material is higher than that of the first coating material. Subsequently, the surface of the second intermediate element, excluding the coupling region, is shielded. Etching material is then sprayed onto the first unshielded area of ​​the second intermediate element to remove both the first and second coating materials deposited on the unshielded coupling region, resulting in a third intermediate element. Finally, the third intermediate element, including the coupling region, is shielded. In the grating region of the coupled region and the grating region, etching material is sprayed onto the second unshielded area of ​​the third intermediate element to remove the second coating material of the unshielded area on the surface of the third intermediate element, thus obtaining the optical waveguide element. Through the above process, it is ensured that both the first and second coating materials deposited on the coupled region are removed, and the optical waveguide element is coated with at least the coupled region. By coating the coupled region with the second coating material, the diffraction efficiency of the optical waveguide substrate can be enhanced, and precise selective coating of the coupled region of the optical waveguide can be achieved. This avoids the problem of light leakage in the coupled region caused by coating the entire surface of the optical waveguide, thereby achieving precise fabrication of the optical waveguide element.

[0051] In some embodiments, such as Figure 2 As shown, before step S102, the method further includes:

[0052] S201, Provide a substrate.

[0053] The substrate can completely cover the surface of the coupling region on the optical waveguide substrate. That is, the outline dimensions of the substrate can be the same as or larger than the outline dimensions of the optical waveguide substrate surface. The substrate material must be cut to ensure it can block coating and etching materials, such as transparent substrates (glass substrates, resin substrates, etc.) and flexible mask materials (polycarbonate (PC), polydimethylsiloxane (PDMS), etc.).

[0054] S202. According to the boundary position information of the coupling region on the surface of the optical waveguide substrate, the first solid plate is separated from the substrate to obtain the first perforated plate.

[0055] The first solid plate can be assembled into the opening area of ​​the first perforated plate; the outline of the first solid plate has the same dimensions as the outline of the coupling area.

[0056] The boundary position information on the surface of the optical waveguide substrate of the coupling region can indicate the outline size of the coupling region and its position on the surface of the optical waveguide substrate. Based on the boundary position information of the optical waveguide substrate of the coupling region, a mask pattern corresponding to the coupling region can be planned on the substrate (which can be achieved, for example, through photolithography, laser direct writing technology, etc.). Then, based on the mask pattern, the first solid plate and the first aperture plate can be separated from the substrate (which can be achieved, for example, through wet etching, laser cutting, etc.). Specifically, a mask pattern is written on the substrate covered by photosensitive material using a high-precision electron beam or laser exposure system. Afterward, the first solid plate and the first aperture plate can be separated from the substrate by methods such as wet etching, laser cutting, etc.

[0057] like Figure 3 As shown, Figure 3 In the diagram, 310 represents the surface of the optical waveguide substrate, 311 represents the coupling-out region on the surface of the optical waveguide substrate, 312 represents the coupling-in region on the surface of the optical waveguide substrate, and 320 represents the substrate. Figure 3 An exemplary embodiment is shown of a substrate that is completely aligned with the surface 310 of the optical waveguide substrate. The boundary location information of the coupling region on the surface of the optical waveguide substrate will be... Figure 3 The substrate shown is divided to obtain a first perforated plate 410 with an opening area, 411 is the opening area of ​​the first perforated plate, and 420 is the first solid plate obtained by dividing the substrate 320.

[0058] After obtaining the first perforated plate, as Figure 4 As shown, S102 includes:

[0059] S1021. Align the perforated area in the first perforated plate with the coupling area on the optical waveguide substrate. That is, use the unperforated area of ​​the first perforated plate to shield the other areas on the optical waveguide substrate except for the coupling area.

[0060] S1022. The first coating material is sputtered onto the coupling region on the optical waveguide substrate through the opening area in the first opening plate, so as to deposit the first coating material in the coupling region to obtain the first intermediate element.

[0061] The coupling area on the surface of the first intermediate element is coated with a first coating material, while other areas are not coated with the first coating material.

[0062] In the above embodiment, the first aperture plate and the optical waveguide substrate can be placed parallel to each other, ensuring that the aperture area in the first aperture plate is aligned with the coupling area on the optical waveguide substrate, and that the first aperture plate is located between the coating source of the first coating material and the coupling area on the optical waveguide substrate. This ensures that the coating source of the first coating material can sputter the first coating material towards the aperture area of ​​the first aperture plate, so that the first coating material passes through the aperture area in the first aperture plate and is sputtered onto the coupling area on the optical waveguide substrate, ensuring that the first coating material is deposited in the coupling area to obtain the first intermediate element.

[0063] The deposition source for the first coating material can be a deposition source in a magnetron sputtering device used for sputtering the first coating material. The deposition source for the first coating material can sputter the first coating material in a direction perpendicular to the first perforated plate.

[0064] In this embodiment, the first perforated plate can be placed close to the surface of the optical waveguide substrate, and the perforation area of ​​the first perforated plate is aligned with the coupling area on the optical waveguide substrate. In other embodiments, while ensuring that the perforation area of ​​the first perforated plate is aligned with the coupling area on the optical waveguide substrate, the first perforated plate can be placed at intervals from the surface where the coupling area of ​​the optical waveguide substrate is located.

[0065] In one embodiment, the first perforated plate can also be used to shield other areas on the surface of the second intermediate element besides the area where the coupling region is located, such as... Figure 5 As shown, S104 includes:

[0066] S1041. Align the opening area in the first perforated plate with the area where the coupling region is located on the surface of the second intermediate element.

[0067] S1042. The etching material is sprayed from the etching source through the opening area in the first opening plate onto the first unmasked area on the surface of the second intermediate element to remove the second coating material and the first coating material plated on the coupling area, thereby obtaining the third intermediate element.

[0068] The etching source is a jet source used to spray etching material, which can be gas, liquid, or solid. In some embodiments, the etching source can spray gaseous etching material in the form of a plasma beam. The gaseous etching material is excited into high-energy particles in a plasma environment. These particles interact with the second coating material and the first coating material deposited on the first unshielded area through physical collisions or chemical reactions.

[0069] In some embodiments, etching material can be sprayed from an etching source in an ion beam etching apparatus through an opening region in a first perforated plate onto a first unmasked region on the surface of a second intermediate element.

[0070] In some embodiments, S1042 includes: spraying etching material from an etching source through an opening region in a first aperture plate onto a first unmasked region on the surface of a second intermediate element at a target etching rate, so as to remove the second coating material and the first coating material deposited on the coupling region to obtain a third intermediate element; wherein the target etching rate is determined according to the thickness of the first coating material and the thickness of the second coating material in the coupling region.

[0071] The higher the etching rate, the less etching time is required; the lower the etching rate, the more etching time is required.

[0072] The etching source can spray an ion beam of etching material, which bombards the first unmasked area on the surface of the second intermediate element to remove the second and first coating materials deposited on the coupling region. By precisely controlling the ion beam bombardment time through a predetermined target etching rate, the removal of both coating materials on the coupling region is ensured, while preserving the morphology of the coupling region grating. Furthermore, ion beam bombardment improves the roughness of the grating on the coupling region, eliminating concerns about over-etching and enhancing the uniformity of the grating at the coupling region after etching. Since the coupling region is shielded by the non-aperture area of ​​the first aperture plate, the second coating material with a higher refractive index deposited on the coupling region is protected from ion beam bombardment by the etching material.

[0073] In some embodiments, the grating region includes the region containing the coupling-out region and the region containing the coupling-in region; such as Figure 6 As shown, S105 includes:

[0074] S1051, Provide a second physical board.

[0075] The outline of the second solid plate is the same as the outline of the coupling region. The material of the second solid plate can be the same as or different from that of the substrate.

[0076] S1052. Align the area where the coupling region is located on the surface of the first solid plate and the third intermediate element so as to cover the area where the coupling region is located on the surface of the third intermediate element through the first solid plate.

[0077] S1053. Align the area where the coupling region is located on the surface of the second solid plate and the third intermediate element so as to cover the area where the coupling region is located on the surface of the third intermediate element through the second solid plate.

[0078] S1054. Etching material is sprayed from the etching source onto the second unshielded area on the surface of the third intermediate element to remove the second coating material in the second unshielded area, thereby obtaining an optical waveguide element.

[0079] Since the area where the coupling region is located on the surface of the third intermediate element is shielded by the first solid plate, and the area where the coupling region is located on the surface of the third intermediate element is shielded by the second solid plate, the etching material sprayed by the etching source is guaranteed not to reach the area where the coupling region is located and the area where the coupling region is located on the surface of the third intermediate element, but only to reach the second unshielded area on the surface of the third intermediate element, thus ensuring effective removal of the second coating material in the second unshielded area.

[0080] Figure 7 This is a flowchart illustrating a method for fabricating an optical waveguide element according to another embodiment of this application, such as... Figure 7 As shown, it includes:

[0081] ① Magnetron sputtering of the first coating material.

[0082] exist Figure 7 In the process, the opening area 411 in the first opening plate 410 is aligned with the coupling area 311 on the surface 310 of the optical waveguide substrate. Then, the first coating material is directionally sputtered from the coating source of the first coating material through the opening area 411 to the coupling area 311 of the optical waveguide substrate to obtain the first intermediate element 700.

[0083] Among them, the grating area on the left side of the surface of the first intermediate element 700 is the coupling-in region, the grating area on the right side is the coupling-out region, and the gray area on the coupling-out region is the first coating material deposited on the coupling-out region.

[0084] ② A second coating material is deposited using an atomic layer deposition (ALD) device.

[0085] exist Figure 7 In the process, a second coating material is deposited onto the surface 710 of the first intermediate element 700 using an atomic layer deposition device to obtain the second intermediate element 800.

[0086] The black area on the surface of the second intermediate element 800 is the second coating material deposited on the surface of the first intermediate element, and the gray area on the coupling area on the surface of the second intermediate element 800 is the first coating material.

[0087] ③Ion beam etching equipment performs directional etching in one step.

[0088] exist Figure 7 In the process, the opening area 411 in the first opening plate 410 is aligned with the coupling area 811 on the surface 810 of the second intermediate element 800. Then, the etching source of the ion beam etching equipment sprays an ion beam through the opening area 411 to the coupling area 811 of the second intermediate element to obtain the third intermediate element 900.

[0089] In this case, the second coating material and the first coating material deposited on the coupling area of ​​the third intermediate element 900 have been removed, and the other areas except the coupling area are also coated with the second coating material (i.e. the black area on the surface of the third intermediate element).

[0090] ④ Secondary directional etching using ion beam etching equipment.

[0091] exist Figure 7 In the process, the first solid plate 411 is aligned with the area where the coupling region 911 is located on the surface 910 of the third intermediate element 900, and the second solid plate 412 is aligned with the area where the coupling region 912 is located on the surface 910 of the third intermediate element 900. An ion beam is sprayed onto the area on the surface 910 of the third intermediate element that is not covered by the first solid plate 411 and the second solid plate 412 by an ion beam etching device to obtain the optical waveguide element 1000.

[0092] In this process, the coating material on the surface of the optical waveguide element 1000, except for the coupling region, has been removed, leaving a second coating material with a higher refractive index (i.e., the black area on the coupling region).

[0093] In some embodiments, a transition region is further provided on the surface of the optical waveguide substrate; the grating region also includes the region where the transition region is located; before S1054, the method further includes: providing a third solid plate, the outline of the second solid plate being the same as the outline size of the transition region; aligning the third solid plate with the region where the transition region is located on the surface of the third intermediate element, so as to shield the region where the transition region is located on the surface of the third intermediate element through the third solid plate.

[0094] Correspondingly, the second unmasked area on the surface of the third intermediate element includes the other areas on the surface of the third intermediate element besides the areas where the coupling-in area, coupling-out area and transition area are located. That is, the grating area that is masked in step S104 includes the areas where the coupling-in area, coupling-out area and transition area are located.

[0095] In this embodiment, when the grating region also includes a transition region, a second coating material can be deposited on the transition region simultaneously to achieve precise selective coating of the transition region and the coupling region.

[0096] In some embodiments, S102 includes: sputtering a first coating material in a magnetron manner from a magnetron coating source along a direction perpendicular to the surface where the coupling region is located, so that the first coating material passes through the opening area in the first opening plate and is sputtered onto the coupling region on the optical waveguide substrate to form a first intermediate element; the first opening plate is located between the magnetron coating source and the optical waveguide substrate.

[0097] The magnetron sputtering source (i.e., the coating source of the first coating material) sputters the first coating material in a direction perpendicular to the surface where the coupling region is located, which ensures that the first coating material sputtered onto the optical waveguide substrate through the first aperture plate can completely cover the unshielded area (i.e., the coupling region) and will not be deposited on the shielded area (i.e., other areas on the surface of the optical waveguide substrate besides the coupling region).

[0098] With the relative position between the first perforated plate and the optical waveguide substrate fixed, when the first coating material is deposited onto the coupling area by the magnetron coating source, the orientation of the optical waveguide substrate needs to be adjusted in advance so that the magnetron coating source can be oriented to deposit the coating along the vertical direction of the surface where the coupling area is located.

[0099] In some embodiments, during the deposition of a first coating material onto the coupling region of the optical waveguide substrate, the optical waveguide substrate is placed on a motion platform, and a reference grating is placed on the optical waveguide substrate; such as Figure 8 As shown, directional coating of the magnetron coating source along the vertical direction of the surface where the coupling region is located can be achieved through steps S301-S303, as detailed below:

[0100] S301. During the process of depositing the first coating material on the coupling region of the optical waveguide substrate, a reference beam is projected onto at least one reference grating, and the phase information of the reference beam after passing through at least one reference grating is collected.

[0101] like Figure 9 As shown, Figure 9 A schematic diagram showing the positional relationship between an optical waveguide substrate, at least one reference grating, and a motion platform is provided. In the diagram, 1600 is the optical waveguide substrate, 1610 is the reference grating, 1620 is the grating on the coupling region of the optical waveguide substrate, and 1630 is the motion platform. The optical waveguide substrate is placed on the XY plane of the motion platform, and at least one reference grating is placed on the XY plane of the optical waveguide substrate.

[0102] A reference beam is projected onto at least one reference grating. After being reflected by at least one reference grating, the reference beam forms an exposure field on the surface of the optical waveguide substrate. The phase information of the reference beam after passing through at least one reference grating can be acquired by the imaging device 1640.

[0103] S302. Based on phase information and reference phase information, determine the pose error of the motion platform.

[0104] The reference phase information refers to the phase information of the reference beam after passing through at least one reference grating, while ensuring the directional coating of the magnetron coating source along the vertical direction of the surface where the coupling region is located.

[0105] The pose error of the motion platform refers to the error between the current pose of the motion platform and the specified pose of the motion platform, that is, the pose error between the current motion platform and the exposure field formed by the reference beam. The specified pose refers to the pose of the motion platform while ensuring directional coating of the magnetron deposition source along the direction perpendicular to the surface where the coupling region is located.

[0106] In some implementations, S302 includes: obtaining the pose error of the motion platform based on phase information, reference phase information, and the transformation relationship between the phase and the coordinate system in which the motion platform is located.

[0107] S303. Adjust the motion platform based on the pose error to ensure that the magnetron sputtering source sputters the first coating material along the vertical direction of the surface where the coupling area is located.

[0108] The position and orientation of the motion platform are adjusted to the specified orientation based on the pose error to ensure that the magnetron sputtering source sputters the first coating material along the vertical direction of the surface where the coupling region is located.

[0109] like Figure 10 As shown, the positional relationship between the optical waveguide substrate, at least one reference grating, and the motion platform is as follows: Figure 9 As shown, after adjusting the motion platform 1630 based on the pose error, the magnetron coating source can sputter the first coating material along the vertical direction of the surface where the coupling region is located.

[0110] In this embodiment, a reference grating is placed on the surface of the optical waveguide substrate. The pose error of the motion platform is determined by the phase information of the reference beam passing through the reference grating and the reference phase information. By correcting the pose error, it is achieved that the magnetron sputtering source sputters the first coating material in the direction perpendicular to the surface where the coupling region is located, thereby ensuring that the first coating material sputtered by the magnetron sputtering source can completely cover the coupling region and not adhere to other areas other than the coupling region.

[0111] In one embodiment, the coupling-out region and the coupling-in region are located on the first surface of the optical waveguide substrate. The optical waveguide substrate further includes an anti-reflection coating located on the second surface of the optical waveguide substrate, with the first surface opposite to the second surface. The area on the second intermediate element corresponding to the anti-reflection coating is coated with a first coating material. Figure 11 As shown, before S103, the method further includes:

[0112] S401, Provide a second perforated plate.

[0113] Specifically, the outline of the opening area of ​​the second opening plate is the same as the outline size of the optical waveguide substrate. In particular, the outline of the opening area of ​​the second opening plate is the same as the outline size of the second surface of the optical waveguide substrate.

[0114] Anti-reflective coating (AR film) on the second surface of an optical waveguide substrate is a multilayer thin film coated on the second surface to reduce or eliminate reflected light from optical surfaces such as lenses, prisms, and plane mirrors.

[0115] S402. Align the opening area in the second perforated plate with the second surface of the optical waveguide substrate.

[0116] like Figure 12 As shown, in Figure 12 In the diagram, 1800 is the second surface of the optical waveguide substrate, 1810 is the second perforated plate, and 1820 is the perforation area of ​​the second perforated plate.

[0117] S403. The first coating material is sputtered onto the second surface of the optical waveguide substrate through the opening area in the second opening plate to deposit the first coating material on the second surface.

[0118] Figure 13 This is a flowchart illustrating a method for fabricating an optical waveguide element according to another embodiment of this application, such as... Figure 13 As shown, the opening region 1820 in the second opening plate 1810 is aligned with the edge of the second surface 1800 of the optical waveguide substrate. A first coating material is then sputtered from the first coating material's deposition source onto the second surface 1800 of the optical waveguide substrate through the opening region 1820, resulting in an optical waveguide substrate coated on the second surface (e.g., ...). Figure 13 (1200 in the middle).

[0119] Among them, 1210 is an anti-reflection coating on the second surface of the optical waveguide substrate 1200, and the gray area on the anti-reflection coating is the first coating material deposited on the second surface.

[0120] In this embodiment, a first coating material is deposited on the antireflection and anti-reflection film on the second surface of the optical waveguide substrate to avoid the second coating material from being deposited onto the antireflection and anti-reflection film during the deposition process, thus preventing the existing antireflection and anti-reflection film from being damaged.

[0121] It is known that the first coating material on the antireflective coating is used to include the antireflective coating on the optical waveguide, and therefore the first coating material needs to be removed in subsequent processes.

[0122] Correspondingly, such as Figure 14 As shown, S103 includes:

[0123] S1031, shielding the areas on the first surface of the second intermediate element other than the area where the coupling region is located.

[0124] S1032, Etching material is sprayed from the etching source onto the first unmasked area on the first surface of the second intermediate element to remove the first coating material and the second coating material in the first unmasked area.

[0125] S1033. Align the opening area in the second perforated plate with the area where the anti-reflection and anti-reflection film is located on the second intermediate element.

[0126] S1034. Etching material is sprayed from the etching source onto the second intermediate element in the area where the antireflection coating is located, to remove the first coating material and the second coating material in the area where the antireflection coating is located, and to obtain the third intermediate element.

[0127] In this embodiment, since the first coating material deposited on the antireflection and anti-reflection film on the second surface of the second intermediate element can be used to protect the antireflection and anti-reflection film from contamination during the deposition of the second coating material, after the deposition of the second coating material is completed, the first coating material and the second coating material deposited on the antireflection and anti-reflection film on the second surface of the second intermediate element are removed to ensure that the antireflection and anti-reflection film of the finally prepared optical waveguide element is not damaged and its performance is not affected.

[0128] This application also provides a display device, comprising: the display device including an optical waveguide element prepared according to any of the foregoing embodiments. The display device may be an augmented reality device, such as AR glasses, an AR head-mounted device, etc., and is not specifically limited herein.

[0129] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application.

Claims

1. A method of producing an optical waveguide element, characterized by, include: An optical waveguide substrate is provided, wherein the surface of the optical waveguide substrate is provided with a coupling-out region and a coupling-in region; The optical waveguide substrate is shielded from all areas except the coupling region, and a first coating material is deposited in the coupling region to obtain a first intermediate element. A second coating material is deposited on the surface of the first intermediate element to obtain a second intermediate element; the refractive index of the second coating material is greater than the refractive index of the optical waveguide substrate. The surface of the second intermediate element is shielded except for the area where the coupling region is located, and etching material is sprayed onto the first unshielded area on the surface of the second intermediate element to remove the second coating material and the first coating material deposited on the coupling region, thereby obtaining the third intermediate element; A grating region on the surface of the third intermediate element is shielded, and etching material is sprayed onto a second unshielded region on the surface of the third intermediate element to remove the second coating material in the second unshielded region, thereby obtaining an optical waveguide element; the grating region includes at least the region where the coupling-out region is located and the region where the coupling-in region is located.

2. The method according to claim 1, characterized in that, The method further includes: A substrate is provided, which can completely cover the surface of the optical waveguide substrate where the coupling region is located; According to the boundary position information of the coupling region on the surface of the optical waveguide substrate, a first solid plate is divided from the substrate to obtain a first perforated plate. The first solid plate can be assembled into the perforated area in the first perforated plate. The outline of the first solid plate is the same as the outline size of the coupling region. The process of shielding the optical waveguide substrate from other areas except the coupling region, and depositing a first coating material on the coupling region of the optical waveguide substrate to obtain a first intermediate element includes: Align the opening area in the first perforated plate with the coupling area on the optical waveguide substrate. The first coating material is sputtered onto the coupling region on the optical waveguide substrate through the opening area in the first perforated plate, so as to deposit the first coating material in the coupling region to obtain the first intermediate element.

3. The method according to claim 2, characterized in that, The surface of the second intermediate element is shielded from areas other than the coupling region, and etching material is sprayed onto the first unshielded area on the surface of the second intermediate element to remove the second and first coating materials deposited on the coupling region, thereby obtaining a third intermediate element, comprising: Align the opening area in the first perforated plate with the area where the coupling region is located on the surface of the second intermediate element. The etching material is sprayed from the etching source through the opening area in the first perforated plate onto the first unmasked area on the surface of the second intermediate element to remove the second coating material and the first coating material deposited on the coupling area, thereby obtaining the third intermediate element.

4. The method according to claim 2, characterized in that, The grating region includes the region where the coupling-out region is located and the region where the coupling-in region is located; The grating region on the surface of the third intermediate element is shielded, and etching material is sprayed onto the second unshielded region on the surface of the third intermediate element to remove the second coating material in the second unshielded region, thereby obtaining an optical waveguide element, comprising: A second solid plate is provided; the outline of the second solid plate has the same dimensions as the outline of the coupling region. Align the first solid plate with the area where the coupling region is located on the surface of the third intermediate element so as to cover the area where the coupling region is located on the surface of the third intermediate element through the first solid plate. The second solid plate is aligned with the area where the coupling region is located on the surface of the third intermediate element so as to cover the area where the coupling region is located on the surface of the third intermediate element by means of the second solid plate. Etching material is sprayed from an etching source onto a second unshielded area on the surface of the third intermediate element to remove the second coating material in the second unshielded area, thereby obtaining an optical waveguide element.

5. The method according to claim 4, characterized in that, The surface of the optical waveguide substrate is further provided with a transition region; the grating region also includes the region where the transition region is located. Before the step of spraying etching material from an etching source onto a second unmasked area on the surface of the third intermediate element to remove the second coating material in the second unmasked area and obtain the optical waveguide element, the method further includes: A third solid plate is provided, wherein the outline of the second solid plate has the same dimensions as the outline of the transition zone; The third solid plate is aligned with the area where the transition zone is located on the surface of the third intermediate element, so as to cover the area where the transition zone is located on the surface of the third intermediate element through the third solid plate.

6. The method according to claim 2, characterized in that, The step of sputtering a first coating material through an opening area in the first perforated plate onto the coupling area of ​​the optical waveguide substrate, to deposit the first coating material in the coupling area to obtain a first intermediate element, includes: A first coating material is sputtered by a magnetron sputtering source along the vertical direction of the surface where the coupling region is located, so that the first coating material passes through the opening area in the first opening plate and is sputtered onto the coupling region on the optical waveguide substrate to form the first intermediate element; the first opening plate is located between the magnetron sputtering source and the optical waveguide substrate.

7. The method according to claim 6, characterized in that, During the process of depositing a first coating material onto the coupling region on the optical waveguide substrate, the optical waveguide substrate is placed on a motion platform, and a reference grating is placed on the optical waveguide substrate. The method further includes: During the process of depositing a first coating material on the coupling region of the optical waveguide substrate, a reference beam is projected onto the at least one reference grating, and the phase information of the reference beam after passing through the at least one reference grating is collected. Based on the phase information and the reference phase information, the pose error of the motion platform is determined; The motion platform is adjusted based on the pose error to ensure that the magnetron sputtering source sputters the first coating material along the direction perpendicular to the surface where the coupling region is located.

8. The method according to any one of claims 1 to 7, characterized in that, The coupling-out region and the coupling-in region are located on the first surface of the optical waveguide substrate. The optical waveguide substrate also includes an anti-reflection coating, which is located on the second surface of the optical waveguide substrate. The first surface and the second surface are opposite to each other. The area on the second intermediate element corresponding to the anti-reflection coating is coated with a first coating material. Before depositing a second coating material onto the surface of the first intermediate element to obtain the second intermediate element, the method further includes: A second perforated plate is provided; the outline of the perforated area of ​​the second perforated plate is the same as the outline dimension of the optical waveguide substrate; Align the opening area in the second perforated plate with the second surface of the optical waveguide substrate. The first coating material is sputtered onto the second surface of the optical waveguide substrate through the opening area in the second opening plate to deposit the first coating material on the second surface; The surface of the second intermediate element is shielded from areas other than the coupling region, and etching material is sprayed onto the first unshielded area on the surface of the second intermediate element to remove the second and first coating materials deposited on the coupling region, thereby obtaining a third intermediate element, comprising: The area on the first surface of the second intermediate element, excluding the area where the coupling region is located, is shielded. Etching material is sprayed from the etching source onto a first unmasked area on the first surface of the second intermediate element to remove the first and second coating materials in the first unmasked area. Align the opening area in the second perforated plate with the area where the anti-reflection and anti-reflection film is located on the second intermediate element. Etching material is sprayed from the etching source onto the second intermediate element in the area where the antireflective coating is located, to remove the first and second coating materials in the area where the antireflective coating is located, thereby obtaining the third intermediate element.

9. The method according to claim 3, characterized in that, The process of spraying etching material from an etching source through the opening area in the first perforated plate onto the first unmasked area on the surface of the second intermediate element to remove the second and first coating materials deposited on the coupling area, thereby obtaining the third intermediate element, includes: The etching source sprays the etching material through the opening area in the first aperture plate onto the first unmasked area on the surface of the second intermediate element at a target etching rate, so as to remove the second coating material and the first coating material deposited on the coupling area, thereby obtaining the third intermediate element; wherein, the target etching rate is determined according to the thickness of the first coating material and the thickness of the second coating material in the coupling area.

10. The method according to any one of claims 1 to 7 and 9, characterized in that, The step of depositing a second coating material onto the surface of the first intermediate element to obtain the second intermediate element includes: A second intermediate element is obtained by depositing a second coating material on the surface of the first intermediate element using an atomic layer deposition device.

11. The method according to any one of claims 1 to 7 and 9, characterized in that, After shielding the grating region on the surface of the third intermediate element and spraying etching material onto the second unshielded region on the surface of the third intermediate element to remove the second coating material in the second unshielded region to obtain the optical waveguide element, the method further includes: If the first coating material remains on the optical waveguide element, wet etching is performed on the remaining first coating material on the optical waveguide element.

12. The method according to claim 1, characterized in that, The second coating material is any one of zinc oxide, titanium oxide, and hafnium oxide.

13. The method according to claim 1, characterized in that, The coating thickness of the second coating material on the second intermediate element is 0.1nm-100nm.

14. A display device, characterized in that, This includes optical waveguide elements prepared according to any one of claims 1-13.

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