Preparation method of polarization body holographic device and polarization body holographic device

Abstract

The invention provides a preparation method of a polarization body holographic device and the polarization body holographic device. The method comprises the following steps: providing a substrate layer; coating a light orientation layer on the substrate layer, and carrying out polarization exposure treatment on the light orientation layer; coating a liquid crystal material on the photo-alignment layer subjected to the polarization exposure treatment, and carrying out photo-alignment and curing treatment on the liquid crystal to form a liquid crystal layer; the surface of the side, away from the substrate layer, of the liquid crystal layer is coated with a bonding layer, and a device layer is attached to the bonding layer; and removing the substrate layer and the light orientation layer to obtain the polarization body holographic device. When the polarization body holographic device is prepared, the light orientation layer and the substrate layer are removed, the problems that the polarization body holographic device becomes yellow and absorbs blue-violet light due to the existence of the light orientation layer and the substrate layer are solved, and the optical performance of the polarization body holographic device is improved.

Description

Technical Field

[0001] The present application relates to the technical field of grating preparation, and in particular to a method for preparing a polarization holographic device and a polarization holographic device. Background Art

[0002] Polarimetric holographic devices have significant advantages such as high diffraction efficiency, wide wavelength bandwidth and wide angle bandwidth. The polarimetric holographic grating in the polarimetric holographic device is particularly suitable as an in-coupled grating or out-coupled grating of a large field angle, color diffraction optical waveguide in an augmented reality near-eye display device. In the existing scheme for preparing polarimetric holographic devices, it is necessary to use a photo-orientation layer to orient the liquid crystal in the polarimetric holographic device so that the liquid crystal molecules have a periodic orientation arrangement. However, the photo-orientation layer is usually composed of azo dyes, which have colors themselves and have a certain absorption effect on blue-violet light, which will have a certain impact on the optical properties of the prepared polarimetric holographic device. Summary of the invention

[0003] The present application provides a method for preparing a polarization volume holographic device and a polarization volume holographic device, aiming to reduce the influence of the method for preparing the polarization volume holographic device on the prepared polarization volume holographic device.

[0004] In a first aspect, the present application provides a method for preparing a polarization volume holographic device, and the method for preparing a polarization volume holographic device comprises the following steps:

[0005] Provides a base layer;

[0006] Coating a photo-alignment layer on the base layer, and performing a polarization exposure treatment on the photo-alignment layer;

[0007] coating a liquid crystal material on the photo-alignment layer that has undergone polarized exposure treatment, and performing photo-alignment and curing treatment on the liquid crystal to form a liquid crystal layer;

[0008] Coating an adhesive layer on the surface of the liquid crystal layer facing away from the substrate layer, and laminating a device layer to the adhesive layer;

[0009] The base layer and the optical alignment layer are removed to obtain the polarizer holographic device.

[0010] In some embodiments, removing the base layer and the photo-alignment layer comprises:

[0011] The base layer and the photo-alignment layer are removed by mechanical grinding and polishing or chemical mechanical polishing.

[0012] In some embodiments, removing the base layer and the photo-alignment layer comprises:

[0013] When the bonding force between the bonding layer and the device layer and between the bonding layer and the liquid crystal layer is greater than the bonding force between the liquid crystal layer and the photo alignment layer, removing the base layer and the photo alignment layer by one of mechanical separation, mechanical grinding and polishing, and chemical mechanical polishing;

[0014] When the bonding force between the bonding layer and the device layer and between the bonding layer and the liquid crystal layer is greater than the bonding force between the photo-alignment layer and the substrate layer, the substrate layer is removed from the photo-alignment layer by mechanical separation, and then the photo-alignment layer is removed by etching or corrosion.

[0015] In some embodiments, the base layer includes a flexible base sublayer, an adhesive sublayer and a rigid base sublayer, the adhesive sublayer is used to bond the flexible base sublayer and the rigid base sublayer, and the photo alignment layer is disposed on the flexible base sublayer; the method further includes:

[0016] After forming the liquid crystal layer, separating the flexible substrate sublayer from the adhesive sublayer to remove the rigid substrate sublayer and the adhesive sublayer;

[0017] After the device layer is bonded, the flexible substrate sublayer and the photo-alignment layer are removed.

[0018] In some embodiments, the base layer includes a flexible base sublayer, an adhesive sublayer and a rigid base sublayer, the adhesive sublayer is used to bond the flexible base sublayer and the rigid base sublayer, and the photo alignment layer is disposed on the flexible base sublayer;

[0019] The removing of the base layer and the photo-alignment layer comprises:

[0020] Separating the flexible base sublayer from the adhesive sublayer to remove the rigid base sublayer and the adhesive sublayer;

[0021] The photo alignment layer is separated from the liquid crystal layer by mechanical separation to remove the photo alignment layer; or after the flexible substrate sublayer is separated from the photo alignment layer, the photo alignment layer is removed by etching or corrosion.

[0022] In some embodiments, the step of separating the photo alignment layer from the liquid crystal layer by mechanical separation includes:

[0023] In a case where the bonding force between the flexible substrate sublayer and the photo alignment layer is greater than the bonding force between the photo alignment layer and the liquid crystal layer, the photo alignment layer and the liquid crystal layer are separated based on the flexible substrate sublayer by mechanical separation.

[0024] In some embodiments, the method further comprises:

[0025] The liquid crystal layer in the polarization holographic device is subjected to photolithography processing so that different regions of the liquid crystal layer have different thicknesses.

[0026] In some embodiments, coating a photo-alignment layer on the base layer comprises:

[0027] The photo alignment layer is coated on the base layer by spin coating or spray coating.

[0028] In some embodiments, the polarization exposure treatment of the photo-alignment layer includes:

[0029] The photo-alignment layer is subjected to polarized exposure treatment through an exposure light field, wherein the exposure light field is a light field obtained by interference of at least two polarized lights, or the exposure light field is a vector polarized light field.

[0030] In some embodiments, the exposure light field is obtained by double-beam interference of the polarized light or interference of polarization mask diffraction light.

[0031] In some embodiments, the exposure light field is obtained by interference of left-handed circularly polarized light and right-handed circularly polarized light.

[0032] In a second aspect, the present application further provides a polarization volume holographic device, which is manufactured by the method for manufacturing a polarization volume holographic device as provided in the first aspect.

[0033] In some embodiments, the device layer in the polarizer holographic device includes a first surface and a second surface relative to each other, the first surface is bonded to the bonding layer in the polarizer holographic device; the first surface and the second surface are both planes; or the first surface is a plane and the second surface is a curved surface.

[0034] The present application provides a method for preparing a polarizer holographic device and a polarizer holographic device. The present application obtains a polarizer holographic device by removing a substrate layer and a photo-orientation layer after completing photo-orientation and curing of liquid crystals and lamination of device layers, so that the polarizer holographic device will not turn yellow due to the presence of the photo-orientation layer, and will not have the problem of absorbing blue-violet light, thereby improving the optical performance of the polarizer holographic device. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0036] Figure 1 A schematic flow chart of a method for preparing a polarization volume holographic device provided in one embodiment of the present application;

[0037] Figure 2 A flow chart for preparing a polarization volume hologram provided in one embodiment of the present application;

[0038] Figure 3 A structural diagram of a substrate layer provided in another embodiment of the present application;

[0039] Figure 4 A schematic structural diagram of a polarization holographic device provided in another embodiment of the present application;

[0040] Figure 5 A schematic block diagram of the structure of a polarization holographic device provided in one embodiment of the present application;

[0041] Figure 6 This is a schematic structural diagram of a polarization holographic device provided in another embodiment of the present application. DETAILED DESCRIPTION

[0042] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0043] The flowcharts shown in the accompanying drawings are only examples and do not necessarily include all the contents and operations / steps, nor must they be executed in the order described. For example, some operations / steps may also be decomposed, combined or partially merged, so the actual execution order may change according to actual conditions.

[0044] The present application provides a method for preparing a polarization holographic device and a polarization holographic device. The polarization holographic device prepared by the method for preparing a polarization holographic device can be applied to an optical waveguide of an augmented reality (AR) near-eye display device as a diffraction microstructure on the optical waveguide for coupling in and / or coupling out light.

[0045] In conjunction with the accompanying drawings, some embodiments of the present application are described in detail below. In the absence of conflict, the following embodiments and features in the embodiments can be combined with each other.

[0046] See also Figure 1 and Figure 2 , Figure 1 FIG. 1 is a flow chart of a method for preparing a polarization volume holographic device 100 provided in one embodiment of the present application. Figure 2 This is a flow chart of the preparation of a polarization holographic device 100 provided in one embodiment of the present application.

[0047] like Figure 1 As shown, the method for preparing the polarization holographic device 100 includes steps S101 to S104.

[0048] Step S101 : providing a base layer 110 .

[0049] Exemplarily, the base layer 110 required for preparing the polarization volume hologram device 100 is provided, so that the preparation of the polarization volume hologram device 100 is completed based on the base layer 110 .

[0050] For example, during the preparation of the polarization hologram device 100 , the base layer 110 can be used as a supporting structure to provide mechanical stability and flatness to the polarization hologram device 100 during the preparation process, thereby improving the preparation convenience of the polarization hologram device 100 .

[0051] Step S102 : coating a photo alignment layer 120 on the base layer 110 , and performing a polarized light exposure process on the photo alignment layer 120 .

[0052] For example, Figure 2 As shown in step (a), a photo-alignment layer 120 is coated on the base layer 110, and the photo-alignment layer 120 after coating is subjected to polarized exposure treatment so that the alignment material molecules in the photo-alignment layer 120 correspond to the polarization direction of the light, thereby forming the orientation of the photo-alignment layer 120.

[0053] In some embodiments, coating the photo alignment layer 120 on the base layer 110 includes coating the photo alignment layer 120 on the base layer 110 by one of spin coating, spray coating, and inkjet printing coating.

[0054] It should be understood that the photo-alignment layer 120 may be coated on the base layer 110 by spin coating, spray coating, inkjet printing, or other coating methods, so that the photo-alignment layer 120 on the base layer 110 can be subjected to polarized exposure treatment using polarized light.

[0055] For example, the optical alignment layer 120 may be subjected to polarized exposure treatment by a preset light source, wherein the preset light source includes but is not limited to an ultraviolet light source, a laser light source, and other light sources.

[0056] In some embodiments, performing polarized exposure processing on the photo alignment layer 120 includes: performing polarized exposure processing on the photo alignment layer 120 through an exposure light field, wherein the light source of the exposure light field is polarized light.

[0057] Exemplarily, the photo-alignment layer 120 is exposed by an exposure light field to induce the arrangement of the alignment material molecules in the photo-alignment layer 120 , thereby forming the orientation of the photo-alignment layer 120 .

[0058] For example, the photo alignment layer 120 is exposed by a point-by-point scanning exposure method, wherein the polarization direction of each point is different, so as to complete the exposure of the photo alignment layer 120 .

[0059] It should be noted that the above exposure light field and exposure method are only examples, and do not limit the specific exposure light field and exposure method used for the photo-alignment layer 120 .

[0060] In some embodiments, the exposure light field is obtained by interference of at least two polarized light beams or by a polarization mask.

[0061] For example, at least two polarized lights are interfered on the surface of the photo-alignment layer 120 to perform polarized exposure on the photo-alignment layer 120, thereby inducing the alignment material molecules in the photo-alignment layer 120 to produce a corresponding arrangement, thereby completing the alignment of the photo-alignment layer 120. Alternatively, an exposure light field is obtained through a polarization mask, for example, a preset light source is irradiated on the polarization mask, and light passing through the polarization mask is used as the exposure light field, thereby achieving polarized exposure of the photo-alignment layer 120.

[0062] In some embodiments, the at least two polarizations include left-handed circularly polarized light and right-handed circularly polarized light.

[0063] In other embodiments, an exposure light field is generated by polarized light having a specific polarization state and a polarization mask; specifically, after the polarized light passes through a polarization mask having the function of non-uniformly converting the polarization state in space, a polarized exposure light field required for exposing the light orientation layer 120 is formed, so that the polarized exposure light field can be used to induce the alignment material molecules in the light orientation layer 120 to produce a corresponding arrangement, thereby completing the orientation of the light orientation layer 120.

[0064] It should be understood that the above-mentioned methods of generating polarized exposure light fields are all examples, and those skilled in the art can select light to generate polarized exposure light fields according to actual needs. This application does not limit the specific method of generating polarized exposure light fields.

[0065] Step S103 : coating a liquid crystal material on the photo-alignment layer 120 that has undergone the polarized exposure treatment, and performing photo-alignment and curing treatment on the liquid crystal material to form a liquid crystal layer 130 .

[0066] For example, after the alignment of the photo-alignment layer 120 is completed, Figure 2As shown in step (c) in the above, a liquid crystal material is coated on the photo-alignment layer 120 so that the liquid crystal material is aligned by the photo-alignment layer 120 ; and then the liquid crystal material is cured to form a liquid crystal layer 130 .

[0067] In the specific implementation process, the coated liquid crystal is a polymerizable cholesteric liquid crystal material, and the polymerizable cholesteric liquid crystal coated on the photo-alignment layer 120 is exposed and cured, so that the orientation of the liquid crystal molecules is changed under the orientation of the photo-alignment layer 120, and then the liquid crystal monomers in the polymerizable cholesteric liquid crystal are polymerized to form a polymer network to fix the orientation of the liquid crystal molecules. It should be understood that after the liquid crystal molecules complete the cross-linking reaction, the orientation of the liquid crystal molecules will be fixed due to the cross-linking, so there is no need to use the photo-alignment layer 120 to align the orientation of the liquid crystal molecules. Therefore, after the liquid crystal layer 130 is cured, removing the photo-alignment layer 120 will not affect the orientation of the liquid crystal molecules in the liquid crystal layer 130.

[0068] Step S104 , disposing a device layer 140 on a side of the liquid crystal layer 130 away from the substrate layer 110 .

[0069] Exemplarily, after the liquid crystal layer 130 is prepared, a device layer 140 is disposed on the side of the liquid crystal layer 130 facing away from the substrate layer 110 , wherein the bonded device layer 140 includes but is not limited to a flat device or a curved device.

[0070] In some embodiments, the device layer 140 is provided on the side of the liquid crystal layer away from the substrate layer 110, including: providing an adhesive layer 150 on the surface of the liquid crystal layer 130 away from the substrate layer 110, so as to bond the liquid crystal layer 130 and the device layer 140 through the adhesive layer 150.

[0071] For example, after forming the liquid crystal layer 130, Figure 2 As shown in step (d) in the above, an adhesive layer 150 is coated on the surface of the liquid crystal layer 130 which is away from the substrate layer 110; after the adhesive layer 150 is formed, Figure 2 As shown in step (e) in the embodiment, the device layer 140 is bonded to the surface of the bonding layer 150 facing away from the liquid crystal layer 130 to complete the arrangement of the device layer 140.

[0072] In other embodiments, the device layer 140 is provided on the side of the liquid crystal layer 130 away from the substrate layer 110 , including: the liquid crystal layer 130 is sticky, and the device layer 140 is attached and bonded to the surface of the liquid crystal layer 130 away from the substrate layer 110 .

[0073] Exemplarily, the liquid crystal layer 130 has viscosity, so that it can be bonded to the device layer 140 to complete the arrangement of the device layer 140. In a specific implementation process, if the device layer 140 is bonded by the liquid crystal layer 130, then in step S103, the coated liquid crystal material is pre-cured to allow the liquid crystal material to retain viscosity, and after the device layer 140 is bonded by the viscosity of the liquid crystal material, the liquid crystal material is cured to completely cure the liquid crystal material, forming a stable liquid crystal layer 130 and firmly bonding to the device layer 140.

[0074] Step S105 , removing the base layer 110 and the optical alignment layer 120 to obtain the polarization volume holographic device 100 .

[0075] Exemplarily, after the bonding of the device layer 140 is completed, as Figure 2 As shown in step (f) of the method, the substrate layer 110 and the photo-alignment layer 120 are removed to obtain the polarization hologram device 100. It can be understood that the polarization hologram device 100 prepared by the above steps includes the device layer 140, the adhesive layer 150 and the liquid crystal layer 130, or includes the device layer 140 and the liquid crystal layer 130; and after the photo-alignment layer 120 and the substrate layer 110 are removed, the polarization hologram device 100 will not turn yellow due to the presence of the photo-alignment layer 120, and the problem of the prepared polarization hologram device 100 absorbing blue-violet light is avoided; and because the photo-alignment layer 120 is removed, the thickness of the photo-alignment layer 120 can be appropriately increased during the preparation process to meet the orientation requirements of the liquid crystal material, and the final polarization hologram device 100 will not turn yellow or absorb blue-violet light due to the presence of an overly thick photo-alignment layer 120, thereby ensuring the optical performance of the polarization hologram device 100.

[0076] In some embodiments, removing the base layer 110 and the photo-alignment layer 120 includes: removing the base layer 110 and the photo-alignment layer 120 by mechanical grinding and polishing or chemical mechanical polishing.

[0077] In a specific embodiment, the mechanical grinding and polishing method includes but is not limited to polishing the ground position after grinding the base layer 110 and the photo-alignment layer 120 with a sanding belt or a grinder to obtain the polarization holographic device 100. Chemical mechanical polishing (CMP) is a surface treatment technology that combines chemical etching and mechanical grinding. Specifically, after chemically etching the base layer 110 and the photo-alignment layer 120 with a chemical liquid, the etched surface is polished by mechanical grinding to complete the removal of the base layer 110 and the photo-alignment layer 120.

[0078] In some specific implementation processes, removing the base layer 110 and the photo alignment layer 120 includes: when the bonding force between the adhesive layer 150 and the device layer 140 and between the adhesive layer 150 and the liquid crystal layer 130 is greater than the bonding force between the liquid crystal layer 130 and the photo alignment layer 120, removing the base layer 110 and the photo alignment layer 120 by one of mechanical separation, mechanical grinding and polishing, and chemical mechanical polishing.

[0079] For example, the bonding force between the adhesive layer 150 and the device layer 140, and the bonding force between the liquid crystal layer 130 and the photo-alignment layer 120 are determined by determining the surface viscosity of the materials used to prepare each layer; or the bonding force between the adhesive layer 150 and the device layer 140, and the bonding force between the liquid crystal layer 130 and the photo-alignment layer 120 in a device are determined by experiment, and then the bonding force between each layer in the device obtained in the same production batch or the same production environment is confirmed. If the bonding force between the adhesive layer 150 and the device layer 140 is greater than the bonding force between the liquid crystal layer 130 and the photo-alignment layer 120, and the bonding force between the adhesive layer 150 and the liquid crystal layer 130 is greater than the bonding force between the liquid crystal layer 130 and the photo-alignment layer 120, the photo-alignment layer 120 can be separated from the liquid crystal layer 130 by a mechanical separation method such as tearing, so as to remove the base layer 110 and the photo-alignment layer 120. It should be understood that under this condition, when mechanical force is applied to the base layer 110 or the photo alignment layer 120 and the base layer 110 is torn off, since the bonding force between the adhesive layer 150 and the device layer 140 and the bonding force between the adhesive layer 150 and the liquid crystal layer 130 are both greater than the bonding force between the liquid crystal layer 130 and the photo alignment layer 120, during the tearing process, the adhesive layer 150 will not be torn off, and the device layer 140, the adhesive layer 150 and the liquid crystal layer 130 can still maintain a bonding state, thereby achieving the effect of tearing off the photo alignment layer 120, realizing the separation of the photo alignment layer 120 and the liquid crystal layer 130, thereby achieving the purpose of removing the base layer 110 and the photo alignment layer 120.

[0080] In a specific implementation process, if the bonding strength of the adhesive layer 150 and the bonding strength of the optical alignment layer 120 meet the aforementioned conditions, the optical alignment layer 120 and the liquid crystal layer 130 can be directly separated by mechanical separation, thereby improving the convenience of removing the base layer 110 and the optical alignment layer 120.

[0081] In other embodiments, when the bonding force between the adhesive layer 150 and the device layer 140 and between the adhesive layer 150 and the liquid crystal layer 130 is greater than the bonding force between the photo orientation layer 120 and the substrate layer 110, and the bonding force between the photo orientation layer 120 and the liquid crystal layer 130 is greater than the bonding force between the photo orientation layer 120 and the substrate layer 110, the substrate layer 110 is removed from the photo orientation layer 120 by mechanical separation, and then the photo orientation layer 120 is removed by etching or corrosion.

[0082] Exemplarily, since the bonding force between the bonding layer 150 and the device layer 140 and the bonding force between the bonding layer 150 and the liquid crystal layer 130 are both greater than the bonding force between the photo alignment layer 120 and the base layer 110, and the bonding force between the photo alignment layer 120 and the liquid crystal layer 130 is greater than the bonding force between the photo alignment layer 120 and the base layer 110, the base layer 110 can be removed from the photo alignment layer 120 by mechanical separation, for example, the base layer 110 is torn off from the photo alignment layer 120; After the base layer 110 is torn off from the photo-alignment layer 120, the photo-alignment layer 120 is still on the liquid crystal layer 130, and then the photo-alignment layer 120 is removed by etching or corrosion. Specifically, the photo-alignment layer 120 on the liquid crystal layer 130 is removed by plasma etching or chemical solution corrosion to complete the removal of the base layer 110 and the photo-alignment layer 120, thereby obtaining a polarization holographic device 100 including a device layer 140, an adhesive layer 150 and a liquid crystal layer 130.

[0083] See also Figure 3 , Figure 3 This is a structural diagram of a base layer 110 provided in another embodiment of the present application.

[0084] In some embodiments, the base layer 110 includes a flexible base sublayer 111, an adhesive sublayer 112 and a rigid base sublayer 113, the adhesive sublayer 112 is used to bond the flexible base sublayer 111 and the rigid base sublayer 113, and a light orientation layer 120 is provided on the flexible base sublayer 111; removing the base layer 110 and the light orientation layer 120 includes: separating the flexible base sublayer 111 from the adhesive sublayer 112 to remove the rigid base sublayer 113 and the adhesive sublayer 112, and then separating the light orientation layer 120 from the liquid crystal layer 130 by mechanical separation to remove the light orientation layer 120.

[0085] Exemplarily, the base layer 110 is composed of a flexible base sublayer 111, an adhesive sublayer 112, and a rigid base sublayer 113, wherein the adhesive sublayer 112 is used to connect the flexible base sublayer 111 and the rigid base sublayer 113, and the photo alignment layer 120 is disposed on the flexible base sublayer 111. In the process of removing the base layer 110 and the photo alignment layer 120, a force may be applied to the rigid base sublayer 113 to first separate the flexible base sublayer 111 from the adhesive sublayer 112 to remove the rigid base sublayer 113 and the adhesive sublayer 112; and then a force may be applied to the flexible base sublayer 111 to separate the photo alignment layer 120 from the liquid crystal layer 130 to remove the photo alignment layer 120, thereby completing the removal of the base layer 110 and the photo alignment layer 120. The photo alignment layer 120 and the base layer 110 are removed by a relatively simple and convenient mechanical separation method, thereby improving the convenience and efficiency of preparation.

[0086] In some embodiments, the photo alignment layer 120 is separated from the liquid crystal layer 130 by a mechanical separation method, including: when the bonding force between the flexible substrate sublayer 111 and the photo alignment layer 120 is greater than the bonding force between the photo alignment layer 120 and the liquid crystal layer 130, the photo alignment layer 120 is separated from the liquid crystal layer 130 based on the flexible substrate sublayer 111 by a mechanical separation method.

[0087] In a specific implementation process, if the bonding force between the flexible substrate sublayer 111 and the photo alignment layer 120 is greater than the bonding force between the photo alignment layer 120 and the liquid crystal layer 130, in the process of tearing off the flexible substrate sublayer 111, the photo alignment layer 120 can be torn off from the liquid crystal layer 130 together, so as to achieve the purpose of removing the photo alignment layer 120 and the substrate layer 110.

[0088] In other embodiments, after the flexible substrate sublayer 111 is separated from the photo alignment layer 120 to remove the rigid substrate sublayer 113 , the adhesive sublayer 112 and the flexible substrate sublayer 111 , the photo alignment layer 120 is removed by etching or corrosion.

[0089] Exemplarily, if the flexible base sublayer 111 and the photo-alignment layer 120 can be separated by mechanical separation, thereby achieving the removal of the rigid base sublayer 113, the adhesive sublayer 112 and the flexible base sublayer 111, the photo-alignment layer 120 is removed by etching or corrosion to complete the removal of the base layer 110 and the photo-alignment layer 120.

[0090] In the specific implementation process, since the bonding force between the flexible substrate sublayer 111 and the photo orientation layer 120 is less than or equal to the bonding force between the photo orientation layer 120 and the liquid crystal layer 130, in the process of tearing off the flexible substrate sublayer 111, only the flexible substrate sublayer 111 will be torn off from the photo orientation layer 120. After tearing off the flexible substrate sublayer 111, the photo orientation layer 120 on the liquid crystal layer 130 is removed by plasma etching or chemical solution corrosion, thereby completing the removal of the substrate layer 110 and the photo orientation layer 120.

[0091] In some embodiments, the base layer 110 includes a flexible base sublayer 111, an adhesive sublayer 112 and a rigid base sublayer 113, the adhesive sublayer 112 is used to bond the flexible base sublayer 111 and the rigid base sublayer 113, and a photo orientation layer 120 is provided on the flexible base sublayer 111; the method also includes: after forming the liquid crystal layer 130, separating the flexible base sublayer 111 from the adhesive sublayer 112 to remove the rigid base sublayer 113 and the adhesive sublayer 112; after bonding the device layer 140, removing the flexible base sublayer 111 and the photo orientation layer 120.

[0092] In a specific implementation process, the photo-orientation layer 120 is disposed on the flexible substrate sub-layer 111. After the liquid crystal layer 130 is formed on the photo-orientation layer 120, the flexible substrate sub-layer 111 is firstly separated from the adhesive sub-layer 112 to remove the rigid substrate sub-layer 113; and after the rigid substrate sub-layer 113 is removed, the coating of the adhesive layer 150 and the bonding of the device layer 140 are completed; and after the bonding of the device layer 140 is completed, the photo-orientation layer 120 is separated from the liquid crystal layer 130 to remove the photo-orientation layer 120 and the substrate layer 110.

[0093] Exemplarily, the flexible substrate sublayer 111 and the photo alignment layer 120 are removed by one of mechanical separation, mechanical grinding and polishing, and chemical mechanical polishing. The specific removal process of the flexible substrate sublayer 111 and the photo alignment layer 120 can refer to the above-mentioned embodiment of removing the substrate layer 110 and the photo alignment layer 120, which will not be repeated here.

[0094] Alternatively, the flexible substrate sublayer 111 is first removed from the photo alignment layer 120 by mechanical separation, and then the photo alignment layer 120 is removed by etching or corrosion. It should be understood that if the bonding force between the flexible substrate sublayer 111 and the photo alignment layer 120 is smaller than the bonding force between the photo alignment layer 120 and the liquid crystal layer 130, the photo alignment layer 120 cannot be torn off together with the flexible substrate sublayer 111. Therefore, after the flexible substrate sublayer 111 is torn off, the photo alignment layer 120 is plasma etched or chemically corroded to complete the removal of the photo alignment layer 120, thereby obtaining the polarization volume holographic device 100 including the device layer 140, the adhesive layer 150 and the liquid crystal layer 130.

[0095] It should be understood that since both the liquid crystal layer 130 and the flexible substrate sublayer 111 have a certain toughness, the flexible substrate sublayer 111 is separated from the adhesive sublayer 112 after the liquid crystal layer 130 is formed, which is more conducive to the separation of the rigid substrate sublayer 113, avoiding the problem of separation difficulty caused by the substrate layer 110 and the device layer 140 being made of rigid materials, thereby improving the convenience of removing the substrate layer 110.

[0096] See also Figure 4 , Figure 4 This is a schematic structural diagram of a polarization volume holographic device 100 provided in another embodiment of the present application.

[0097] In some embodiments, the method further includes: performing photolithography on the liquid crystal layer 130 in the polarization holographic device 100 so that different regions of the liquid crystal layer 130 have different thicknesses.

[0098] Exemplarily, after removing the substrate layer 110 and the photo-alignment layer 120, the liquid crystal layer 130 is subjected to mask lithography and / or plasma etching, so that different regions of the liquid crystal layer 130 have different corresponding thicknesses. When the polarization volume holographic device 100 with uneven thickness of the liquid crystal layer 130 is used as a coupling-in structure and / or coupling-out structure of a diffraction light waveguide, it can improve the brightness uniformity and color uniformity of the display, so that the corresponding AR near-eye display device has a better display effect.

[0099] It should be noted that the polarization hologram device 100 obtained by the above-mentioned method for preparing the polarization hologram device 100 includes but is not limited to a polarization hologram grating and a polarization hologram lens, and the present application does not limit the specific polarization hologram device 100.

[0100] The method for preparing the polarization holographic device 100 provided in the above embodiment comprises the following steps: firstly forming the photo-alignment layer 120 on the substrate layer 110, so as to complete the formation of the liquid crystal layer 130 by using the photo-alignment layer 120, and then bonding the device layer 140 by using the bonding layer 150 provided on the liquid crystal layer 130, and then separating the photo-alignment layer 120 from the liquid crystal layer 130, so as to remove the photo-alignment layer 120 and the substrate layer 110, and obtaining the polarization holographic device 100 including the device layer 140, the bonding layer 150 and the liquid crystal layer 130. 20 is removed from the prepared polarizer hologram device 100, so that in the process of preparing the polarizer hologram device 100, the thickness of the optical orientation layer 120 can be increased to obtain a better orientation effect on the liquid crystal, thereby improving the preparation effect of the polarizer hologram device 100, and removing the optical orientation layer 120 and the substrate layer 110 also avoids the problem of yellowing and absorbing blue-violet light in the prepared polarizer hologram device 100 due to the existence of the optical orientation layer 120, thereby ensuring the optical performance of the prepared polarizer hologram device 100.

[0101] See also Figure 5 , Figure 5 This is a schematic block diagram of the structure of a polarization volume holographic device 100 provided in one embodiment of the present application.

[0102] As shown in the figure, the polarizer hologram device 100 is manufactured by the preparation method of the polarizer hologram device 100 provided in any of the foregoing embodiments, that is, the polarizer hologram device 100 includes a device layer 140, an adhesive layer 150 and a liquid crystal layer 130. After the base layer 110 and the optical orientation layer 120 required for the preparation process are removed from the polarizer hologram device 100, the problem of device luminescence and light absorption can be avoided, thereby ensuring the optical performance of the polarizer hologram device 100.

[0103] In some embodiments, the device layer 140 in the polarization holographic device 100 includes a first surface and a second surface opposite to each other, the first surface is bonded to the bonding layer in the polarization holographic device 100; the first surface and the second surface are both planes; or the first surface is a plane and the second surface is a curved surface.

[0104] In a specific embodiment, Figure 5 As shown, the first surface and the second surface of the device layer 140 are both planar.

[0105] See also Figure 6 , Figure 6 This is a schematic structural diagram of a polarization volume holographic device 100 provided in another embodiment of the present application.

[0106] In other embodiments, Figure 6 As shown, the first surface of the device layer 140 is a plane, and the second surface is a curved surface, so as to adapt to the actual application requirements of the polarization holographic device 100.

[0107] It should be understood that the terms used in this application specification are only for the purpose of describing specific embodiments and are not intended to limit the application. As used in this application specification and the appended claims, unless the context clearly indicates otherwise, the singular forms "a", "an" and "the" are intended to include plural forms.

[0108] It should also be understood that the term "and / or" used in the specification of this application and the appended claims refers to any combination of one or more of the associated listed items and all possible combinations, including these combinations. It should be noted that, in this article, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or system including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or system. In the absence of further restrictions, an element defined by the sentence "including a..." does not exclude the presence of other identical elements in the process, method, article or system including the element.

[0109] The serial numbers of the embodiments of the present application are for description only and do not represent the advantages and disadvantages of the embodiments. The above are only specific implementation methods of the present application, but the protection scope of the present application is not limited thereto. Any technician familiar with the technical field can easily think of various equivalent modifications or replacements within the technical scope disclosed in the present application, and these modifications or replacements should be included in the protection scope of the present application. Therefore, the protection scope of the present application shall be based on the protection scope of the claims.

Claims

1. A method for preparing a polarization holographic device, characterized in that: include: Provides a base layer; Coating a photo-alignment layer on the base layer, and performing a polarization exposure treatment on the photo-alignment layer; coating a liquid crystal material on the photo-alignment layer that has undergone polarized exposure treatment, and performing photo-alignment and curing treatment on the liquid crystal to form a liquid crystal layer; Disposing a device layer on a side of the liquid crystal layer away from the substrate layer; The base layer and the optical alignment layer are removed to obtain the polarizer holographic device.

2. The method according to claim 1, characterized in that The removing of the base layer and the photo-alignment layer comprises: The base layer and the photo-alignment layer are removed by at least one of mechanical separation, mechanical grinding and polishing, and chemical mechanical polishing.

3. The method for preparing a polarization holographic device according to claim 1, characterized in that: The device layer is arranged on a side of the liquid crystal layer away from the substrate layer, comprising: Disposing an adhesive layer on the surface of the liquid crystal layer facing away from the substrate layer, so as to adhere the liquid crystal layer and the device layer via the adhesive layer; or The liquid crystal layer is sticky, and the device layer is attached and bonded to a surface of the liquid crystal layer on a side away from the substrate layer.

4. The method for preparing a polarization holographic device according to claim 1, characterized in that: The base layer includes a flexible base sublayer, an adhesive sublayer and a rigid base sublayer, the adhesive sublayer is used to bond the flexible base sublayer and the rigid base sublayer, and the photo alignment layer is disposed on the flexible base sublayer; the method further includes: After forming the liquid crystal layer, separating the flexible substrate sublayer from the adhesive sublayer to remove the rigid substrate sublayer and the adhesive sublayer; After the device layer is bonded, the flexible substrate sublayer and the photo-alignment layer are removed.

5. The method for preparing a polarization holographic device according to claim 1, characterized in that: The base layer includes a flexible base sublayer, an adhesive sublayer and a rigid base sublayer, the adhesive sublayer is used to bond the flexible base sublayer and the rigid base sublayer, and the photo alignment layer is disposed on the flexible base sublayer; The removing of the base layer and the photo-alignment layer comprises: Separating the flexible base sublayer from the adhesive sublayer to remove the rigid base sublayer and the adhesive sublayer; The photo alignment layer is separated from the liquid crystal layer by mechanical separation to remove the photo alignment layer; or after the flexible substrate sublayer is separated from the photo alignment layer, the photo alignment layer is removed by etching or corrosion.

6. The method for preparing a polarization holographic device according to any one of claims 1 to 5, characterized in that: The method further comprises: The liquid crystal layer in the polarization holographic device is subjected to photolithography processing so that different regions of the liquid crystal layer have different thicknesses.

7. The method for preparing a polarization holographic device according to any one of claims 1 to 5, characterized in that: The method of coating a photo-alignment layer on the base layer comprises: The photo alignment layer is coated on the base layer by one of spin coating, spray coating and inkjet printing coating.

8. The method for preparing a polarization holographic device according to any one of claims 1 to 5, characterized in that: The step of performing polarization exposure treatment on the photo-alignment layer comprises: The photo-alignment layer is subjected to polarized exposure treatment through an exposure light field, wherein the light source of the exposure light field is polarized light.

9. The method for preparing a polarization holographic device according to claim 8, characterized in that: The exposure light field is obtained through interference of the at least two polarized light beams or a polarization mask.

10. A polarization holographic device, characterized in that: The polarization holographic device is prepared by the method for preparing the polarization holographic device according to any one of claims 1 to 9.

11. The polarization holographic device according to claim 10, characterized in that: The device layer in the polarization holographic device comprises a first surface and a second surface opposite to each other, the first surface is bonded to the bonding layer in the polarization holographic device; the first surface and the second surface are both planes; or the first surface is a plane and the second surface is a curved surface.

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