Waveguide element manufacturing method based on injection molding process, and waveguide element

Abstract

Disclosed are a waveguide element manufacturing method based on an injection molding process, and a waveguide element obtained by the manufacturing method. The waveguide element comprises: an obliquely toothed beam splitting element, a primary lens, and a compensating lens. The obliquely toothed beam splitting element is an obliquely toothed thin film composed of multiple transmissive films and multiple beam-splitting films which are alternately arranged. The size of the primary lens is equivalent to that of a viewing lens. A recess is provided in the primary lens, and a bottom surface of the recess has a tooth tip structure. The dimensions of the compensating lens are the same as the dimensions of the recess, and the side of the compensating lens facing the recess has a tooth tip structure. The compensating lens sandwiches the obliquely toothed beam splitting element between the tooth tip structure of the recess and the tooth tip structure of the compensating lens. According to the disclosed waveguide element manufacturing method, the integrated obliquely toothed beam splitting element is provided, an in-mold injection molding process is used to integrally form the obliquely toothed beam splitting element and the primary lens or the compensating lens, and then the primary lens is adhered to the compensating lens to manufacture the waveguide element, thereby simplifying the manufacturing process of the waveguide element.

Description

Waveguide component manufacturing method based on injection molding process and waveguide component Technical Field

[0001] The present invention relates to a method for manufacturing a waveguide component based on an injection molding process, and also relates to a waveguide component manufactured by the method. Background Art

[0002] Arrayed waveguides, also known as geometric waveguides, utilize multiple parallel partially reflective surfaces within a substrate to form an outcoupling element, effectively coupling light along the visual axis. Within a two-dimensional arrayed waveguide, a steering element is also incorporated, consisting of parallel partially reflective surfaces. The orientation of the steering element differs from that of the outcoupling element.

[0003] The manufacturing method for arrayed waveguides, as disclosed in Chinese patent document CN107111135B, includes the following steps: providing a plurality of transparent plates, each with two opposite surfaces polished so that the surfaces are parallel to one another; applying a partially reflective coating to one surface of the transparent plates, joining the plurality of transparent plates together to form a stack, and cutting the stack along parallel planes at an oblique angle to the surfaces of the transparent plates to form an optical element. Manufacturing arrayed waveguides using this method is complex, difficult, and costly, making it difficult to scale. To ensure process accuracy, most arrayed waveguides are made of glass, resulting in heavy lenses and poor drop resistance.

[0004] Summary of the Invention

[0005] The primary technical problem to be solved by the present invention is to provide a method for manufacturing a waveguide element based on an injection molding process.

[0006] Another technical problem to be solved by the present invention is to provide a waveguide element obtained by the above manufacturing method.

[0007] In order to achieve the above technical objectives, the present invention adopts the following technical solutions:

[0008] According to a first aspect of an embodiment of the present invention, a method for manufacturing a waveguide element based on an injection molding process is provided, comprising the following steps:

[0009] Providing a mold for a primary mirror including a planar waveguide element having a predetermined oblique tooth-shaped groove formed therein, wherein a bottom surface of the groove is provided with a tooth tip structure;

[0010] Provide an oblique tooth-shaped spectroscopic element; the oblique tooth-shaped spectroscopic element is an oblique tooth-shaped film formed by arranging multiple spectroscopic films and multiple transmissive films alternately and connecting them in sequence, and the oblique tooth-shaped spectroscopic element is a layer of contoured spectroscopic film;

[0011] Placing the oblique tooth-shaped beam splitting element in an injection mold of a primary mirror of a waveguide element, and manufacturing a primary mirror with oblique tooth-shaped beam splitting characteristics by an in-mold injection molding process;

[0012] A compensating mirror having a tooth tip structure manufactured by an in-mold injection molding process is provided, wherein the compensating mirror is configured to directly form a matching structure that can be embedded in the oblique tooth-shaped groove of the main mirror;

[0013] The compensating mirror is embedded in the groove of the primary mirror and bonded, so that the oblique tooth-shaped light splitting element is sandwiched between the bottom surface of the groove and the tooth tip structure of the compensating mirror.

[0014] According to a second aspect of an embodiment of the present invention, a method for manufacturing a waveguide element based on an injection molding process is provided, characterized by comprising the following steps:

[0015] A primary mirror of a waveguide element having a predetermined groove is provided by an in-mold injection molding process, wherein the bottom surface of the groove has a tooth tip structure of an oblique tooth shape;

[0016] Provide an oblique tooth-shaped beam splitter element; the oblique tooth-shaped beam splitter element is an oblique tooth-shaped film formed by arranging multiple beam splitter films and multiple transmission films alternately and connecting them in sequence, and the oblique tooth-shaped beam splitter element is a layer of contoured beam splitter film;

[0017] Providing an injection mold for a compensation mirror having a predetermined oblique tooth tip structure, placing the oblique tooth-shaped beam splitting element in the injection mold for the compensation mirror, and processing the compensation mirror having the oblique tooth-shaped beam splitting feature through an in-mold injection molding process;

[0018] The compensating mirror is embedded in the groove of the primary mirror and bonded, so that the oblique tooth-shaped light splitting element is sandwiched between the bottom surface of the groove and the tooth tip structure of the compensating mirror.

[0019] Preferably, when manufacturing an oblique tooth-shaped spectroscopic element, a roughly planar translucent film material is first provided, and spectroscopic film areas are formed by coating spectroscopic films on multiple areas on the surface of the translucent film material. When coating the spectroscopic film, a flat mask is used to block the adjacent spectroscopic film areas to form transmissive film areas, and the spectroscopic film areas and the transmissive film areas are arranged alternately; then, by means of hot bending or contour pressing, the multiple spectroscopic film areas and the multiple transmissive film areas are respectively formed into a spectroscopic film array and a transmissive film array, so that the shape of the film material is consistent with the shape of the tooth tip structure in the waveguide groove.

[0020] Preferably, in the prismatic film array, the reflectivity of the prismatic films is between 5% and 80%, and the transmission-reflection ratio of the plurality of prismatic films gradually decreases along the propagation direction of the light.

[0021] Preferably, the light transmittance of the transmissive film is not less than 98%.

[0022] Preferably, the oblique tooth-shaped groove has an asymmetric structure, and the characteristic angle between adjacent beam splitting films and transmission films is between 45° and 90°.

[0023] According to a third aspect of an embodiment of the present invention, there is provided a waveguide element manufactured by the above-mentioned waveguide element manufacturing method, comprising:

[0024] At least one oblique tooth-shaped beam splitter element, the oblique tooth-shaped beam splitter element is an oblique tooth-shaped film composed of a plurality of transmissive films and a plurality of beam splitter films arranged alternately, wherein the plurality of transmissive films and the plurality of beam splitter films are arranged in different directions, and the plurality of transmissive films and the plurality of beam splitter films are arranged alternately and sequentially connected to form the oblique tooth-shaped film;

[0025] A main mirror, the main mirror being of a size comparable to that of the diopter lens, and having a groove therein, the bottom surface of the groove having a tooth tip structure having the same shape as that of the oblique toothed film;

[0026] at least one compensation mirror, wherein the size of the compensation mirror is the same as the size of the groove, and the compensation mirror has a tooth tip structure having the same shape as the oblique toothed film on a side facing the groove;

[0027] The compensation mirror is embedded in the groove of the primary mirror, and the oblique tooth-shaped light splitting element is clamped between the tooth tip structure of the groove and the tooth tip structure of the compensation mirror.

[0028] Preferably, the number of the oblique tooth-shaped light splitting elements is two, namely: a steering element and a coupling element;

[0029] The primary mirror is provided with two grooves for accommodating a steering element and an outcoupling element respectively;

[0030] There are two compensation mirrors, which are used to fix the deflection element and the outcoupling element in corresponding grooves respectively.

[0031] Preferably, the outcoupling element is arranged at a position of the primary mirror corresponding to the visual axis of the human eye;

[0032] The deflection element is arranged at the end of the primary mirror away from the visual axis of the human eye.

[0033] Preferably, a diopter compensation plate is provided at a position corresponding to the outcoupling area on the surface of the waveguide element close to the human eye, and an air gap exists between the diopter compensation plate and the waveguide element.

[0034] Preferably, both side surfaces of the waveguide element are flat or curved, and there is a difference in surface shape between the two side surfaces to provide visual compensation.

[0035] Preferably, a transmittance compensation film is provided on the surface of the primary mirror provided with the groove, and the transmittance compensation film forms an opening at a position corresponding to the oblique-toothed beam splitting element.

[0036] Preferably, a protective film is provided on the surface of the primary mirror away from the compensation mirror.

[0037] Preferably, the primary mirror, the protective film, and the transmittance compensation film are injection molded into an assembly at one time.

[0038] The waveguide element provided by the present invention includes: at least one oblique tooth-shaped spectrometer element, a primary mirror, and at least one compensation mirror, wherein the oblique tooth-shaped spectrometer element is an oblique tooth-shaped thin film composed of a transmission film array and a spectrometer film array; a groove is provided in the primary mirror, the bottom surface of the groove is provided with a tooth tip structure, and the compensation mirror is constructed to directly form a matching structure that can be embedded in the oblique tooth-shaped groove of the primary mirror, and the bottom surface of the compensation mirror is provided with a tooth tip structure. The compensation mirror and the oblique tooth-shaped spectrometer element are embedded in the groove of the primary mirror, and the oblique tooth-shaped spectrometer element is sandwiched between the tooth tip structure of the primary mirror and the tooth tip structure of the compensation mirror. The above-mentioned waveguide element is manufactured by providing an integrated oblique tooth-shaped spectrometer element, embedding it into the injection mold of the primary mirror or the compensation mirror, and using an in-mold injection molding process to manufacture the primary mirror and the compensation mirror separately. The main mirror and the compensation mirror are then glued together to manufacture a waveguide element with oblique tooth-shaped spectrometer characteristics, thereby simplifying the structure and manufacturing process of the waveguide element. The above-mentioned oblique tooth-shaped spectrometer element can be a steering element located in the steering area or a coupling element located in the coupling area. Through the in-mold injection molding process, the manufacture of one-dimensional array waveguide elements and two-dimensional array waveguide elements can be achieved. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] FIG1 is a schematic structural diagram of a one-dimensional waveguide element provided by the present invention;

[0040] FIG2 is a schematic diagram of an exploded structure of a one-dimensional waveguide element provided by the present invention;

[0041] FIG3 is another schematic diagram of the decomposed structure of the one-dimensional waveguide element provided by the present invention;

[0042] FIG4 is a schematic diagram of the optical path of the one-dimensional waveguide element shown in FIG1 ;

[0043] FIG5 is a schematic structural diagram of an oblique tooth-shaped spectrometer element in a one-dimensional waveguide element;

[0044] FIG6 is a schematic structural diagram of a primary mirror in a one-dimensional waveguide element;

[0045] FIG7 is a schematic structural diagram of a compensation mirror in a one-dimensional waveguide element;

[0046] FIG8 , FIG9 and FIG10 are respectively deformation examples of the one-dimensional waveguide element provided by the present invention;

[0047] FIG11 is a schematic structural diagram of a two-dimensional waveguide element provided by the present invention;

[0048] FIG12 is another schematic structural diagram of the two-dimensional waveguide element provided by the present invention. DETAILED DESCRIPTION

[0049] The technical solution of the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0050] As shown in FIG1 , the one-dimensional waveguide element 10 provided by the present invention is used to realize near-eye display of augmented reality, and includes a substrate 11, a coupling end 12, and a coupling out element 13, wherein the substrate 11 is made of a light-transmitting material, the coupling end 12 is arranged on one side of the substrate 11, and the coupling out element 13 is embedded in the substrate 11 at a position away from the coupling end 12. The coupling out element 13 includes an array formed by a plurality of splitting surfaces, which correspond to the coupling out region of the waveguide element 10. The center of the coupling out element 13 corresponds to the visual axis of the human eye when in use. The collimated light emitted by the projection optical machine enters the substrate 11 through the coupling end 12, undergoes multiple total reflections in the substrate 11, and is coupled out of the waveguide through the coupling out element 13 and enters the human eye for imaging; at the same time, the ambient light passes through the substrate and enters the human eye for imaging, thereby superimposing a virtual image on the basis of the real environment imaging to achieve an augmented reality display effect.

[0051] The specific structure of the one-dimensional waveguide element provided by the present invention is shown in Figures 2 and 3, and includes: an oblique-toothed beam splitter element 20, a primary mirror 30, and a compensation mirror 40; wherein the oblique-toothed beam splitter element 20 is an oblique-toothed film composed of a plurality of transmissive films and a plurality of beam splitter films arranged alternately; the primary mirror 30 is of the same size as the diopter lens; a groove 31 is provided at a position of the primary mirror 30 corresponding to the outcoupling region; the bottom surface of the groove 31 has a tooth tip structure having the same shape as that of the oblique-toothed film; the size of the compensation mirror 40 is the same as that of the groove 31; the surface of the compensation mirror 40 facing the groove 31 is provided with a tooth tip structure having the same shape as that of the oblique-toothed film; the compensation mirror 40 and the oblique-toothed beam splitter element 20 are embedded in the groove 31 of the primary mirror 30, and the oblique-toothed beam splitter element 20 is sandwiched between the tooth tip structure on the bottom surface of the groove 31 and the tooth tip structure of the compensation mirror 40.

[0052] As shown in Figure 4, the primary mirror 30 and the compensation mirror 40 together form the translucent substrate of the optical waveguide element. The oblique-toothed beam splitter element 20 is positioned in the outcoupling region of the substrate. The multiple beam splitter films within the oblique-toothed beam splitter element 20 form a beam splitter film array 22, which functions as an outcoupling beam splitter array. This array is used to expand light transmitted by total internal reflection within the substrate and couple the light out of the substrate toward the human eye. The reflectivity of the beam splitter films ranges from 5% to 80%, with the beam splitter films at different locations exhibiting varying reflectivity. The transmittance-reflectivity ratio of the multiple beam splitter films decreases gradually along the direction of light propagation. The multiple transmissive films within the oblique-toothed beam splitter element 20 form a transmissive film array 21, which transmits light. The transmissive film array 21 and the beam splitter film array 22 are integrally connected to form an oblique-toothed thin film. Therefore, the light transmittance of the transmissive films within the array should be no less than 98%, preferably greater than 99.5%, to ensure that as much light as possible passes through the transmissive films, thereby reducing stray light generated by reflection from the transmissive films.

[0053] Figure 5 shows a schematic structural diagram of a skewed beam splitter element 20. The skewed beam splitter element 20 is a skewed film composed of a transmissive film array 21 and a spectroscopic film array 22. The transmissive film array 21 includes multiple parallel transmissive films, and the spectroscopic film array 22 includes multiple parallel spectroscopic films. The multiple transmissive films and the spectroscopic films are arranged in different directions. Furthermore, the multiple transmissive films and the spectroscopic films are alternately arranged and sequentially connected to form the skewed film. Adjacent transmissive films and spectroscopic films form a spectroscopic unit. The width of a spectroscopic unit varies inversely with the number of spectroscopic elements included in the outcoupling region. The greater the width of a spectroscopic unit, the fewer spectroscopic units are included in the outcoupling region. Preferably, the spectroscopic unit width is 0.2 mm to 3 mm. The skewed beam splitter element includes 5 to 50 spectroscopic units, and the characteristic angle (the angle formed by the two films) between adjacent transmissive films and spectroscopic films forming the skewed state is between 45° and 90°. Each time light passes through the beam splitter film, part of it will be coupled out, and the remaining part will continue to be transmitted downward. The light will continue to be transmitted downward after being refracted by the transmission surface. This coupling feature can effectively eliminate stray light at the coupling end.

[0054] To achieve uniform energy distribution of the outcoupled light, the transmittance-reflectance ratios of the multiple bezels in the bezel array 22 gradually decrease along the light propagation direction. Preferably, the entire bezel array 22 is divided into multiple regions along the light propagation direction, with each region employing a bezel with the same transmittance-reflectance ratio. The transmittance-reflectance ratios of the bezels in different regions gradually decrease along the light propagation direction.

[0055] The manufacturing method of the waveguide element based on the injection molding process provided in the application first provides a mold of the primary mirror, a mold of the compensation mirror and an oblique tooth-shaped spectrometer element, then places the oblique tooth-shaped spectrometer element into the mold of the primary mirror or the compensation mirror, and forms the primary mirror or the compensation mirror with the oblique tooth-shaped spectrometer feature by integral injection molding through an in-mold injection molding process, and then glues the injection-molded component to the compensation mirror or the primary mirror so that the oblique tooth-shaped spectrometer element is fixed between the tooth tip structure of the primary mirror and the tooth tip structure of the compensation mirror, thereby obtaining a waveguide element with the oblique tooth-shaped spectrometer feature.

[0056] The oblique toothed spectroscopic element 20 is located between the outcoupling end of the primary mirror 30 and the compensation mirror 40 and is a contoured spectroscopic film. First, a substantially planar translucent film material is provided. Beam-splitting film regions are formed by coating multiple regions of the translucent film material with spectroscopic film. During the coating process, a flat mask is used to block the adjacent spectroscopic film regions to form transmissive film regions. The spectroscopic film regions and the transmissive film regions are alternately arranged in the film. Through methods such as heat bending or contoured pressing, the film shape is made consistent with the waveguide outcoupling end. Multiple spectroscopic film regions are arranged in an array along a first direction, and multiple transmissive film regions are arranged in an array along a second direction. The first and second directions intersect, and a characteristic angle between adjacent spectroscopic and transmissive films is between 45° and 90°. Preferably, the characteristic angle causes the spectroscopic and transmissive films to be asymmetrically distributed on either side of the intersection. Next, the oblique-tooth beam splitter element is built into the injection mold of the primary mirror or the compensating mirror. Through in-mold injection molding, the primary mirror or the compensating mirror is integrated with the composite film (preferably the primary mirror), resulting in a primary mirror or a compensating mirror with oblique-tooth beam splitting characteristics. The primary mirror and the compensating mirror are then glued together to form a waveguide element. After forming the waveguide element, the position of the transmissive film tends to be perpendicular to the surface of the waveguide element substrate. The characteristic angle between adjacent beam splitter and transmissive films varies according to the angle between the oblique teeth and the substrate surface.

[0057] Compared to films with dispersed arrangements, oblique toothed films have the following advantages: they can be formed in a single step, significantly reducing costs and enabling mass production. The waveguide element provided by the present invention comprises an oblique toothed film composed of a spectroscopic film array and a transmissive film array. The oblique toothed film and a primary mirror or compensating mirror are then integrally formed through an in-mold injection molding process, and the primary mirror and compensating mirror are then glued together to achieve the waveguide element's processing, resulting in a simple structure and low cost. Furthermore, by integrating the oblique toothed film into the mold of the primary mirror or compensating mirror to achieve in-mold injection molding of the primary mirror or compensating mirror with oblique toothed spectroscopic features, compared to coating the tooth tip structure of an already injection-molded primary mirror or compensating mirror, this method avoids the occurrence of incomplete coating, such as black edges and black lines, caused by the oblique teeth occluding each other during the coating process.

[0058] Figures 2 and 3 illustrate two structures of a one-dimensional waveguide element, wherein protective films are provided on the front and back surfaces of the substrate. The following description is based on the front-to-back direction of the visual axis of the human eye, with the side of the waveguide element closest to the eye as the back and the side farther from the eye as the front. In the embodiments shown in Figures 2 and 3, the compensating mirror 40 is positioned in a groove on the front side of the primary mirror 30, away from the eye. In other embodiments not shown, the compensating mirror 40 can also be positioned in a groove on the rear side of the primary mirror 30, facing the eye. The placement of the compensating mirror 40 is not limited here.

[0059] In Figure 2, the waveguide component includes an oblique-tooth beam splitter 20, a primary mirror 30, a compensating mirror 40, a protective film 50, and a transmittance compensation film 60. The primary mirror 30 is of comparable size to the diopter lens. A groove 31 is provided on the front surface of the primary mirror 30, facing away from the eye. The oblique-tooth beam splitter 20 and the compensating mirror 40 are embedded in the groove 31 of the primary mirror 30. The oblique-tooth beam splitter 20 and primary mirror 30 or the compensating mirror 40 are integrally injection-molded, and the primary mirror 30 and the compensating mirror 40 are glued together.

[0060] The front surface of the main mirror 30 (excluding the portion of the groove) can be a flat surface or a curved surface, and the rear surface of the main mirror 30 can be a flat surface or a curved surface, so as to adapt to the user's vision through the difference in surface shape between the front and rear surfaces.

[0061] The surface of the compensating lens 40 facing the primary mirror is structured to mate with the groove 31. The front surface of the compensating lens 40, facing away from the eye, has the same profile as the front surface of the primary mirror 30, either flat or curved. After the primary mirror 30 and compensating lens 40 are bonded together, their front surfaces form a uniform, smooth surface. The compensating lens 40, in conjunction with the primary mirror 30, provides perspective-directed visual compensation.

[0062] In Figure 2 , a protective film 50 is installed on the rear side of the primary mirror 30, away from the compensating mirror 40. The size of the protective film 50 is the same as the overall size of the primary mirror 30. The protective film 50 is a hardened coating or layer that protects the primary mirror 30 from damage to its rear surface. Of course, not using the protective film 50 does not affect the normal function of the waveguide component.

[0063] A transmittance compensation film 60 is disposed on the front surface of the primary mirror 30 (i.e., the side facing away from the human eye). The transmittance compensation film 60 has an opening corresponding to the groove 31. The shape of the opening is identical to that of the groove 31 and the compensation mirror 40. The transmittance compensation film 60 is shaped identically to the front surface of the primary mirror 30, excluding the groove 31. The transmittance compensation film 60 is a special protective film that provides transmittance compensation in the see-through direction, ensuring that the color and transmittance of the entire waveguide element (including the outcoupling region and surrounding areas) are substantially consistent in the see-through direction. Furthermore, the transmittance compensation film 60 protects the primary mirror 30 from damage to its front surface.

[0064] As shown in Figure 3, the waveguide element comprises an oblique-toothed beam splitter 20, a primary mirror 30, a compensating mirror 40, a protective film 50, a transmittance compensation film 60, and a diopter compensation sheet 70. The protective film 50 is located on the rear side of the primary mirror 30, away from the compensating mirror 40. The transmittance compensation film 60 is located on the front surface of the primary mirror 30. A diopter compensation sheet 70 is also located on the side of the waveguide element closest to the eye. An air gap exists between the diopter compensation sheet 70 and the primary mirror 30. The diopter compensation sheet 70 and the protective film 50 work together to ensure that the overall image is free of perspective distortion. The diopter compensation sheet ensures both light transmission and diopter compensation in the perspective direction, providing optical power compensation for myopic individuals.

[0065] In this embodiment, the structures of the primary mirror 30 and the compensating mirror 40 are shown in Figures 6 and 7. The primary mirror 30 may be provided with a groove 31 only in the outcoupling region, and the size of the compensating mirror 40 is the same as the outcoupling region. The bottom surface of the groove 31 and the surface of the compensating mirror 40 facing the primary mirror 30 are the same size as the oblique-toothed beam splitter element 20 and have a sharp tooth structure that mates with the oblique-toothed film. The sharp teeth of the primary mirror 30 and the compensating mirror 40 should be as sharp as possible to avoid rounded corners at the tips of the oblique-toothed film, which could cause stray light in the displayed image, and to prevent a grating effect in the perspective direction.

[0066] Figures 8 to 10 illustrate three variations of the primary mirror and compensating mirror. In one embodiment, a groove 31 formed on the front surface of the primary mirror 30 extends beyond the outcoupling region and extends from the outcoupling region to the edge of the primary mirror 30. The compensating mirror 40 has a structure corresponding to the groove 31 and comprises a region corresponding to the outcoupling region and an auxiliary region corresponding to the normal perspective region. Compared to a compensating mirror positioned solely in the outcoupling region, this type of compensating mirror with the auxiliary region is much easier to assemble with the primary mirror.

[0067] Specifically, in the structure shown in FIG8 , the groove 31 extends from the out-coupling region along the arrangement direction of the beam splitting surface to the edge of the primary mirror 30 away from the in-coupling end. The bottom surface of the groove 31 includes a beveled tooth tip structure and a flat portion. Correspondingly, the compensation mirror 40 includes a beveled tooth tip structure and a flat portion. The compensation mirror 40 and the beveled tooth-shaped beam splitting element 20 are embedded in the groove 31 so that the beveled tooth-shaped beam splitting element 20 is sandwiched between the groove 31 and the tooth tip structure of the compensation mirror 40, thereby realizing the processing of the waveguide element.

[0068] In the structure shown in Figure 9, the groove 31 extends bidirectionally from the outcoupling region along the length of the beam splitter surface to the opposite edges of the primary mirror 30. In this embodiment, the tooth tip structure on the bottom surface of the groove 31 extends along the groove 31 to the opposite edges of the primary mirror 30. Correspondingly, the compensating mirror 40 includes a tooth tip structure that extends across the width of the primary mirror. In this embodiment, the length of the oblique-toothed beam splitter element 20 can be the same as that of the outcoupling region or the same as that of the tooth tip structure of the compensating mirror 40. By embedding the compensating mirror 40 and the oblique-toothed beam splitter element 20 into the groove 31, the oblique-toothed beam splitter element 20 is sandwiched between the groove 31 and the tooth tip structure corresponding to the outcoupling region of the compensating mirror 40, thereby achieving substrate processing of the waveguide element. In this embodiment, the length of the beam splitter film in the oblique-toothed beam splitter element 20 is preferably the same as that of the compensating mirror 40, facilitating fabrication of the waveguide element.

[0069] In the structure shown in Figure 10, the groove 31 extends bidirectionally from the outcoupling region to opposite edges of the primary mirror 30 along the length of the beam splitter surface, and also extends along the arrangement direction of the beam splitter surface array to the edge of the primary mirror 30 away from the outcoupling end. In this embodiment, the tooth tip structure on the bottom surface of the groove 31 extends along with the groove 31 to opposite edges of the primary mirror 30; the bottom surface of the groove 31 also includes a flat portion corresponding to the see-through region. Correspondingly, the compensating mirror 40 includes a tooth tip structure extending across the width of the primary mirror and a flat portion corresponding to the see-through region. Similarly, in this embodiment, the length of the oblique tooth-shaped beam splitter element 20 can be the same as that of the outcoupling region or the same as that of the tooth tip structure of the compensating mirror 40. By embedding the compensating mirror 40 and the oblique tooth-shaped beam splitter element 20 in the groove 31, the oblique tooth-shaped beam splitter element 20 is sandwiched between the groove 31 and the tooth tip structure of the compensating mirror 40 corresponding to the outcoupling region, thereby achieving substrate processing of the waveguide element. In this embodiment, the length of the beam splitter film in the oblique-tooth beam splitter element 20 is preferably the same as the length of the tooth tip structure of the compensation mirror 40 , which facilitates the manufacture of the waveguide element.

[0070] The waveguide element provided by the present invention is manufactured by providing an oblique toothed film composed of a beam splitting film array and a transmission film array, and then integrating the oblique toothed film and a primary mirror or a compensation mirror through an in-mold injection molding process, and then gluing the primary mirror and the compensation mirror together to realize the processing of the waveguide element. The structure is simple and the cost is low.

[0071] Table 1 shows a design example of a waveguide element provided by the present invention, wherein the dimensions of the waveguide element in a plane perpendicular to the visual axis are between 20 mm × 15 mm and 55 mm × 40 mm, and the thickness in the visual axis direction is between 0.8 mm and 5 mm; the dimensions of the outcoupling region of the waveguide element are between 12 mm × 15 mm and 30 mm × 30 mm; and the tooth tip structure of the compensation mirror has parameters corresponding to the outcoupling region.

[0072] Table 1 Design parameters of one-dimensional array waveguide elements

[0073] The waveguide element can be manufactured using an in-mold injection process. This process allows the primary mirror or compensating mirror to be integrally molded with the beveled beam splitter element to form a component. This injection-molded component is then bonded to the compensating mirror or primary mirror to complete the entire waveguide element, allowing for simple manufacturing steps.

[0074] The following is a detailed description of the method for manufacturing the waveguide element shown in FIG2 and FIG3 .

[0075] A first method for manufacturing a waveguide component comprises the following steps:

[0076] S101, providing an oblique toothed beam splitter element;

[0077] The oblique toothed beam splitter element is a thin film formed by alternating and connecting multiple beam splitting films and multiple transmission films. The oblique toothed beam splitter element is a layer of contoured beam splitting film.

[0078] During manufacturing, a roughly planar translucent film material is first provided, and translucent film areas are formed by coating translucent film on multiple areas on the surface of the translucent film material. When coating the translucent film, a flat mask is used to block the adjacent translucent film areas to form translucent film areas, and the translucent film areas and the translucent film areas are arranged alternately in the film. Then, by means of hot bending or contour pressing, the multiple translucent film areas and the multiple translucent film areas are respectively formed into an alternately arranged translucent film array and a translucent film array, so that the shape of the film material is consistent with the tooth tip structure in the primary mirror groove, and the angle between the adjacent translucent film and the translucent film meets the characteristic angle requirement.

[0079] S102, providing a mold of a primary mirror including a planar waveguide element having a predetermined oblique tooth-shaped groove formed therein, wherein the bottom surface of the groove has a tooth tip structure.

[0080] S103, placing the oblique-toothed beam splitting element in an injection mold of a primary mirror, and processing the primary mirror with oblique-toothed beam splitting characteristics through an in-mold injection molding process; the oblique-toothed beam splitting element and the primary mirror are integrally injection-molded to form an assembly;

[0081] During injection molding, the oblique tooth-shaped spectrometer is first placed in the injection mold of the primary mirror at a position corresponding to the tooth tip structure of the groove, and molten resin material is injected into the injection mold. After cooling, the component is obtained.

[0082] S104, providing a mold of a compensation mirror having an oblique tooth-shaped protrusion, and manufacturing the compensation mirror through an injection molding process, wherein the compensation mirror is constructed to directly form a matching structure that can be embedded in the oblique tooth-shaped groove of the main mirror; by injecting molten resin material into the injection mold of the compensation mirror, the compensation mirror is obtained after cooling, and a tooth tip structure is formed on the side surface of the compensation mirror facing the main mirror.

[0083] S105, placing the compensation mirror into the groove of the primary mirror, and gluing the two together to form a waveguide element with oblique tooth-shaped light splitting characteristics.

[0084] A second method for manufacturing a waveguide component comprises the following steps:

[0085] S201, providing an oblique-toothed beam splitter element; the manufacturing method of the oblique-toothed beam splitter element is the same as above, which will not be described again.

[0086] S202, providing a primary mirror having a waveguide element with a predetermined groove, and manufacturing the primary mirror through an injection molding process; injecting molten resin material into an injection mold of the primary mirror, and obtaining the primary mirror after cooling, wherein a groove is formed on the surface of the primary mirror, and the bottom surface of the groove has a tooth tip structure.

[0087] S203, providing an injection mold for a compensation mirror having a predetermined oblique tooth-shaped protrusion, wherein the shape of the oblique tooth-shaped protrusion corresponds to the shape of the tooth tip structure of the compensation mirror;

[0088] S204, placing the oblique-toothed beam splitter element in an injection mold of a compensation mirror, and processing the compensation mirror having oblique-toothed beam splitting characteristics through an in-mold injection molding process; the oblique-toothed beam splitter element and the compensation mirror are integrally formed to form an assembly;

[0089] During injection molding, the oblique tooth-shaped spectrometer is first placed in the position corresponding to the tooth tip structure in the injection mold of the compensation mirror, and molten resin material is injected into the injection mold. After cooling, the component is obtained.

[0090] S205, placing the compensation mirror into the groove of the primary mirror, and gluing the two together to form a waveguide element with oblique tooth-shaped light splitting characteristics.

[0091] The above two manufacturing methods respectively realize the combination of the oblique tooth-shaped spectrometer element and the primary mirror or the compensation mirror through the in-mold injection molding process. Both processes can realize the processing of waveguide elements. Among them, it is preferred to place the oblique tooth-shaped spectrometer element into the mold of the primary mirror to realize injection molding with the primary mirror.

[0092] Furthermore, during the injection molding process of steps S102, S103, and S202, the protective film, transmittance compensation film, and the primary mirror may be simultaneously injection molded using an in-mold molding process. The protective film and transmittance compensation film are placed in corresponding positions in a primary mirror mold, and molten resin is injected into the mold. After cooling, the primary mirror having the protective films on its front and back surfaces is obtained.

[0093] By manufacturing waveguide components through the above-mentioned in-mold injection molding process, the complex coating, gluing, and cutting processes can be simplified into a few simple in-mold injection molding steps. The waveguide components can be obtained by gluing. The structure is simple, the steps are simplified, and the process stability and product qualification rate can be greatly improved.

[0094] Figures 11 and 12 illustrate another waveguide element provided by the present invention, a two-dimensional array waveguide comprising a primary mirror 101, an incoupling port 106, two oblique-toothed beam splitting elements, and two compensating mirrors. The two oblique-toothed beam splitting elements are a steering element 102 and an outcoupling element 103. Both steering element 102 and outcoupling element 103 are oblique-toothed thin films composed of a plurality of beam splitting films and a plurality of transmissive films arranged alternately. The steering element 102 and the outcoupling element 103 have different sizes and are positioned at different locations on the substrate. The primary mirror 101 is provided with two recesses, one for accommodating the steering element 102 and the compensating mirror 104, and the other for accommodating the outcoupling element 103 and the compensating mirror 105. The compensating mirrors 104 and 105 are used to secure the steering element 102 and the outcoupling element 103 in their corresponding recesses, respectively. Together with the primary mirror 101, the compensating mirrors 104 and 105 form the substrate of the complete waveguide element.

[0095] The deflection element 102 and the decoupling element 103 are disposed at both ends of the primary mirror 101. The deflection element 102 is disposed in the base plate near the temples, i.e., at the end of the base plate away from the visual axis of the human eye. The decoupling element 103 is disposed in the base plate near the nose pads, with the center of the decoupling element 103 corresponding to the visual axis of the human eye. Preferably, grooves for accommodating the deflection element 102 and the decoupling element 103 are disposed on both sides of the primary mirror 100, wherein the groove corresponding to the decoupling element 103 is disposed toward the eye, while the groove corresponding to the deflection element 102 is disposed away from the eye and extends to the edge of the base plate near the temples. The deflection element 102, which forms an oblique tooth shape, is relatively small in overall size, illustratively having a length of 10 to 30 mm, a width of 2 to 8 mm, and a thickness (height) of 0.8 to 5 mm. This allows the deflection element 102 and the corresponding compensating mirror 104 to be easily enclosed in a frame. The dimension of the deflection element 102 facing the decoupling element 103 is also smaller than the dimension of the decoupling element 103 facing the deflection element.

[0096] The coupling-in port 106 can be located on the side of the primary mirror 101 near the human eye. The coupling-in port 106 is used to direct collimated light into the primary mirror 101. The light entering the primary mirror 101 undergoes total internal reflection within the substrate and is reflected by the deflection element 102 to achieve pupil expansion and deflection in a first direction. The light is then reflected by the decoupling element 103 to achieve pupil expansion and decoupling in a second direction.

[0097] As shown in FIG12 , similar to the one-dimensional waveguide, in the structure of the two-dimensional array waveguide, a protective film 108 and a transmittance compensation film 109 may be further provided on both surfaces of the primary mirror 101 to protect the two surfaces of the primary mirror 101 .

[0098] In this embodiment, the structures of the two oblique-toothed beam splitting elements are identical to those in the one-dimensional waveguide: they are both oblique-toothed thin films composed of a transmission film array and a beam splitting film array. The bottom surfaces of the two grooves provided in the primary mirror have sharp tooth structures corresponding to the structures of the steering element and the outcoupling element, respectively. The compensation mirror has the same shape as the grooves and features sharp teeth on the surface facing the primary mirror. The two oblique-toothed beam splitting elements are secured within the two grooves of the primary mirror via the two compensation mirrors. The structures and manufacturing methods of the primary mirror, oblique-toothed beam splitting elements, and compensation mirrors are identical to those of the one-dimensional waveguide described above and are not further elaborated here.

[0099] In summary, the waveguide element provided by the present invention includes: at least one oblique tooth-shaped spectrometer element, a primary mirror, and a compensation mirror, wherein the oblique tooth-shaped spectrometer element is an oblique tooth-shaped film composed of a transmission film array and a spectrometer film array; there is a groove in the primary mirror, and the compensation mirror and the oblique tooth-shaped spectrometer element are embedded in the groove of the primary mirror, and the oblique tooth-shaped spectrometer element is sandwiched between the groove and the tooth tip structure of the compensation mirror. The above-mentioned waveguide element simplifies the structure and manufacturing process of the waveguide element by providing an integrated oblique tooth-shaped spectrometer element and arranging it between the primary mirror and the compensation mirror. The above-mentioned oblique tooth-shaped spectrometer element can be a steering element located in the steering area, or it can be a coupling element located in the coupling area. The manufacture of one-dimensional array waveguide elements and two-dimensional array waveguide elements can be achieved through the in-mold injection molding process.

[0100] The above describes in detail the waveguide element with a helical beam splitting feature and its manufacturing method provided by the present invention. For those skilled in the art, any obvious modification without departing from the essence of the present invention would constitute an infringement of the patent rights of the present invention and would result in corresponding legal liability.

Claims

1. A method for manufacturing a waveguide component based on an injection molding process, characterized in that The steps include: providing a mold of a primary mirror including a planar waveguide element having a predetermined oblique tooth-shaped groove formed therein, wherein a tooth tip structure is provided on a bottom surface of the groove; Provide an oblique tooth-shaped beam splitter element; the oblique tooth-shaped beam splitter element is an oblique tooth-shaped film formed by arranging a plurality of beam splitters and a plurality of transmission films alternately and connecting them in sequence, and the oblique tooth-shaped beam splitter element is a layer of contoured beam splitter film; Placing the oblique tooth-shaped beam splitting element in an injection mold of a primary mirror of a waveguide element, and manufacturing a primary mirror with oblique tooth-shaped beam splitting characteristics by an in-mold injection molding process; A compensating mirror having a tooth tip structure manufactured by an in-mold injection molding process is provided, wherein the compensating mirror is configured to directly form a matching structure that can be embedded in an oblique tooth-shaped groove of a primary mirror; The compensating mirror is embedded in the groove of the primary mirror and bonded, so that the oblique tooth-shaped light splitting element is sandwiched between the bottom surface of the groove and the tooth tip structure of the compensating mirror.

2. A method for manufacturing a waveguide element based on an injection molding process, characterized in that The steps include: Providing a primary mirror of a waveguide element having a predetermined groove manufactured by an in-mold injection molding process, wherein the bottom surface of the groove has a tooth tip structure of an oblique tooth shape; Provide an oblique tooth-shaped beam splitter element; the oblique tooth-shaped beam splitter element is an oblique tooth-shaped film formed by arranging a plurality of beam splitters and a plurality of transmission films alternately and connecting them in sequence, and the oblique tooth-shaped beam splitter element is a layer of contoured beam splitter film; Providing an injection mold of a compensating mirror having a predetermined oblique tooth tip structure, placing the oblique tooth shaped light splitting element in the injection mold of the compensating mirror, and processing the compensating mirror having the oblique tooth shaped light splitting feature by an in-mold injection molding process; The compensating mirror is embedded in the groove of the primary mirror and bonded, so that the oblique tooth-shaped light splitting element is sandwiched between the bottom surface of the groove and the tooth tip structure of the compensating mirror.

3. A method for manufacturing a waveguide element according to claim 1 or 2, characterized in that: When manufacturing the oblique tooth-shaped spectroscopic element, firstly, a substantially planar light-transmitting film material is provided, and a spectroscopic film region is formed by coating a spectroscopic film on multiple regions on the surface of the light-transmitting film material. A flat mask is used to block the adjacent beam splitting film areas to form a transmission film area, and the beam splitting film areas and the transmission film areas are arranged alternately; then, by means of heat bending or contour pressing, the multiple beam splitting film areas and the multiple transmission film areas are formed into a beam splitting film array and a transmission film array respectively, so that the shape of the film material is consistent with the shape of the tooth tip structure in the waveguide groove.

4. The method for manufacturing a waveguide element according to claim 3, wherein: In the beam splitter film array, the reflectivity of the beam splitter films is between 5% and 80%, and the transmission-reflection ratio of the plurality of beam splitter films gradually decreases along the propagation direction of the light.

5. The method for manufacturing a waveguide element according to claim 4, wherein: The light transmittance of the transmissive film is not less than 98%.

6. The method for manufacturing a waveguide element according to claim 5, characterized in that The oblique tooth-shaped groove has an asymmetric structure, and the characteristic angle between adjacent beam splitting films and transmission films is between 45° and 90°.

7. A waveguide element manufactured according to any one of the waveguide element manufacturing methods of claims 1 to 6, characterized in that include: At least one oblique tooth-shaped beam splitter element, which is an oblique tooth-shaped film composed of a plurality of transmissive films and a plurality of beam splitter films arranged alternately, wherein the arrangement directions of the plurality of transmissive films and the plurality of beam splitter films are different, and the plurality of transmissive films and the plurality of beam splitter films are arranged alternately and connected in sequence to form the oblique tooth-shaped film; A main mirror, the main mirror is of a size comparable to that of the diopter lens, and has a groove in the main mirror, the bottom surface of the groove having a tooth tip structure having the same shape as that of the oblique toothed film; at least one compensation mirror, the size of the compensation mirror being the same as the size of the groove, and the compensation mirror having a tooth tip structure having the same shape as the oblique toothed film on a side facing the groove; The compensation mirror is embedded in the groove of the primary mirror, and the oblique tooth-shaped light splitting element is clamped between the tooth tip structure of the groove and the tooth tip structure of the compensation mirror.

8. The waveguide element according to claim 7, characterized in that: The number of the oblique tooth-shaped light splitting elements is two, namely: a steering element and a coupling element; The primary mirror is provided with two grooves, which are used to accommodate the steering element and the outcoupling element respectively; There are two compensation mirrors, which are used to fix the deflection element and the coupling element in the corresponding grooves respectively.

9. The waveguide element according to claim 8, characterized in that: The outcoupling element is arranged at a position of the primary mirror corresponding to the visual axis of the human eye; The deflection element is arranged at the end of the main mirror away from the visual axis of the human eye.

10. The waveguide element according to claim 7, wherein: A diopter compensation sheet is provided at a position corresponding to the outcoupling area on the surface of the waveguide element close to the human eye, and an air gap exists between the diopter compensation sheet and the waveguide element.

11. The waveguide element according to claim 7, characterized in that: The two side surfaces of the waveguide element are plane surfaces or curved surfaces, and there is a surface shape difference between the two side surfaces to provide visual compensation.

12. The waveguide element according to claim 7, characterized in that: A transmittance compensation film is disposed on the surface of the primary mirror provided with the groove, and the transmittance compensation film forms an opening at a position corresponding to the oblique tooth-shaped beam splitting element.

13. The waveguide element according to claim 12, wherein: A protective film is disposed on a surface of the main mirror away from the compensation mirror.

14. The waveguide element according to claim 13, characterized in that: The primary mirror, the protective film, and the transmittance compensation film are formed into an assembly by one-step injection molding.

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