CN106842397B

CN106842397B - Resin holographic waveguide lens, preparation method thereof and three-dimensional display device

Info

Publication number: CN106842397B
Application number: CN201710006845.5A
Authority: CN
Inventors: 黄文彬; 陈林森; 浦东林; 朱鸣; 乔文; 罗明辉; 赵改娜
Original assignee: Svg Optronics Co ltd; Suzhou University
Current assignee: Suzhou University; SVG Tech Group Co Ltd
Priority date: 2017-01-05
Filing date: 2017-01-05
Publication date: 2020-07-17
Anticipated expiration: 2037-01-05
Also published as: WO2018126760A1; CN106842397A

Abstract

The invention discloses a resin holographic waveguide lens, a preparation method thereof and a three-dimensional display device constructed by the resin holographic waveguide lens. The resin type holographic waveguide lens provided by the invention has good image coupling-in and coupling-out efficiency, has the advantages of low replication cost and high fidelity ratio under the condition that the nano diffraction grating is utilized to ensure enough field angle and observation range, and can be formed by punching without the processing process of a conventional lens.

Description

Resin holographic waveguide lens, preparation method thereof and three-dimensional display device

Technical Field

The invention relates to the technical field of display equipment, in particular to a resin holographic waveguide lens, a preparation method thereof and a three-dimensional display device.

Background

Augmented Reality (AR) technology is a new technology for seamlessly integrating real world information and virtual world information, and is a technology for superposing entity information (visual information, sound, taste, touch and the like) which is difficult to experience in a certain time and space range of the real world originally through computer and other scientific technologies after simulation, so that people can obtain sensory experience beyond reality. Augmented reality technology has great potential in applications such as sophisticated weaponry, aircraft development and development, data model visualization, virtual training, entertainment and art, as well as enhanced reality technology. In addition, the AR has the characteristic of enhancing display output of a real environment, and has more obvious advantages than a virtual display technology VR in the fields of medical research and anatomical training, precision instrument manufacturing and maintenance, military aircraft navigation, engineering design, remote robot control and the like.

The AR technology projects an image to the human eye for imaging through a miniaturized optical system with a high-brightness microdisplay as an image source and a transparent foldback optical element as a display screen. In traditional AR technique, used a plurality of complicated lens groups, the structure is complicated, complete machine weight and volume are on the large side, and the assembly accuracy requires rigorously, and later maintenance is with high costs, and the promotion of display performance is with increase system volume and system weight as the cost. The waveguide lens is a key core component of new generation AR display, combines a total reflection guided wave principle with a diffraction/refraction element, reduces the volume and the weight of a system while realizing large-view-field and large-exit-pupil image output, and in addition, the waveguide lens guides light through transverse waveguides without influencing people to observe a real environment in a vertical direction, so the waveguide lens is an inevitable trend of the existing AR technical development.

US 6,169,613B 1 discloses a waveguide display device based on volume holographic gratings. The described holographic waveguide comprises one waveguide structure and two or three volume grating structures. At the coupling, the image is guided into the optical waveguide by means of a volume or complex grating, the image propagating in the waveguide and being output at the output by means of one or two volume gratings. The chinese patent CN 105549150 a adds a layer of metal grating on the surface of the volume grating of the holographic waveguide, and improves the energy utilization rate of TM light through plasma oscillation. Although the holographic waveguide has a simple structure, the waveguide only plays a role in guiding light, and does not play a role in expanding an observation field, and the volume grating is difficult to copy and has high manufacturing cost.

US 7,751,122B 2 discloses a waveguide lens structure suitable for use in AR displays. The described waveguide lens comprises a waveguide structure and a plurality of semi-reflecting and semi-transparent mirrors embedded in the waveguide. The image is coupled into the waveguide through the embedded full-reflection prism, when the image is transmitted in the waveguide lens, the image can be coupled and output partially when meeting one semi-reflection and semi-transmission lens, and the intensity of the emergent image is uniform in the whole observation range by modulating the reflectivity of the semi-reflection and semi-transmission lenses at different positions. The structure has two main advantages that firstly, the requirement on the size of an input image is relaxed by embedding a plurality of semi-reflecting and semi-transmitting lenses, so that a larger field angle is obtained, and secondly, the image is output in the waveguide through multiple coupling, so that the observation range of human eyes is enlarged. However, the manufacturing process of embedding the plurality of semi-reflective and semi-transparent lenses in the waveguide lens is complex, the cost is high, the waveguide lens is mainly manufactured by traditional optical processing, the possibility of mass production copy hardly exists, in addition, the appearance of the lens with the embedded semi-reflective and semi-transparent lenses presents a plurality of strips to influence the observation of a wearer, and finally, the scheme depends on side image coupling, so that the space occupied by two sides is large, and the observation comfort of the wearer is influenced.

US 2016/0231568 a1 discloses a holographic waveguide lens for augmented reality, which uses a specific grating to couple in and output an image, the image is totally reflected in the waveguide lens, each time the image travels to a mirror surface with the grating, a part of energy is coupled out, the X and Y directions of the image are respectively expanded by the gratings in the X and Y directions, thereby obtaining a large observation range, and the red, green and blue are realized by three holographic waveguide lenses due to the wavelength selection characteristic of the gratings. The scheme used by microsoft has the following advantages: firstly, the sub-wavelength grating has no modulation effect on light in the vertical direction, so that the lens has good penetrability and cannot influence a wearer to observe the surrounding environment; secondly, the lens adopts an image coupling mode with an upper center, so that the observation of a wearer on two sides is not influenced, and the comfort is improved. However, in order to improve the coupling efficiency and ensure that the entire image can be viewed within the viewing range, the lens needs to be made on a high refractive index glass substrate, which causes problems of high lens quality, high cost, and high risk potential.

Disclosure of Invention

At home and abroad, a simple and feasible waveguide lens scheme is not available, and the augmented reality display performance (field angle and observation range) and the low price, light weight and stability of the lens can be considered.

In order to achieve the purpose, the technical scheme of the invention is as follows:

a resin holographic waveguide lens comprises one, two, three or more than three resin holographic waveguide lens units;

the resin holographic waveguide lens unit comprises a polymer substrate and a functional area, wherein a nanometer diffraction grating is arranged in the functional area; the distance between the bottom of the nanometer diffraction grating and the surface of the polymer substrate is more than 0;

the functional region is arranged on the polymer substrate;

or, the resin holographic waveguide lens unit further comprises a functional film, the functional area is arranged on the functional film, and the functional film is arranged on the polymer substrate.

The resin type holographic waveguide lens provided by the invention has good image coupling-in and coupling-out efficiency, has the advantages of low replication cost and high fidelity ratio under the condition that the nano diffraction grating is utilized to ensure enough field angle and observation range, and can be formed by punching without the processing process of a conventional lens.

Preferably, an antireflection film is arranged on the surface of the nanometer diffraction grating.

Preferably, the functional area includes one, two or three of a coupling-in functional area, a relay functional area and an exit functional area, and the nano diffraction gratings arranged in the coupling-in functional area, the relay functional area and the exit functional area are respectively a coupling-in grating for coupling an external light beam into the resin holographic waveguide lens, a relay grating for changing the propagation direction of the light beam in the resin holographic waveguide lens and an exit grating for outputting the light beam propagated in the resin holographic waveguide lens to the outside of the resin holographic waveguide lens.

Preferably, the resin holographic waveguide lens is of a projection type, and the nanometer diffraction grating is positioned on the coupling-in surface; or the resin holographic waveguide lens is in a reflection type, and the nanometer diffraction grating is positioned opposite to the coupling-in surface; the depth of the nanometer diffraction grating arranged on the reflection type resin waveguide lens is equal to or close to half of the depth of the nanometer diffraction grating arranged on the transmission type resin holographic waveguide lens.

Preferably, the resin holographic waveguide lens is formed by overlapping two, three or more than three resin holographic waveguide lens units; the nano diffraction gratings in the functional areas on different resin holographic waveguide lens units correspondingly regulate and control optical signals with different wavelengths, namely the nano diffraction gratings in the functional areas on different resin holographic waveguide lens units have different periods and different arrangements.

Preferably, the period of the coupled grating is 290nm to 410nm, and the grating depth is 100nm to 500 nm; the period of the relay grating is between 200nm and 290nm, and the depth of the grating is between 30nm and 300 nm; the period of the outgoing grating is consistent with that of the incoming grating, and the depth is between 30nm and 300 nm.

Preferably, the period of the coupled grating is 350nm to 480nm, and the grating depth is 100nm to 600 nm; the period of the relay grating is between 250nm and 335nm, and the depth of the grating is between 30nm and 350 nm; the period of the outgoing grating is consistent with that of the incoming grating, and the depth is between 30nm and 400 nm.

Preferably, the period of the coupled grating is between 415nm and 550nm, and the grating depth is between 100nm and 800nm, corresponding to the nano diffraction grating for modulating red light; the period of the relay grating is between 295nm and 390nm, and the grating depth is between 40nm and 400 nm; the period of the outgoing grating is consistent with that of the incoming grating, and the depth is between 30nm and 400 nm.

Preferably, the relay grating is a positive grating, and the grating depth is linearly increased from left to right and from 20nm to 70 nm.

Preferably, the outgoing grating is a positive grating, and the grating depth is linearly increased from top to bottom and from 20nm to 100 nm.

Preferably, the relay grating is a positive grating, and the grating depth is linearly increased from left to right and from 30nm to 90 nm.

Preferably, the exit grating is a positive grating, and the grating depth increases linearly from top to bottom and from 30nm to 130 nm.

Preferably, the relay grating is a positive grating, and the grating depth is linearly increased from 40nm to 100nm from left to right.

Preferably, the outgoing grating is a positive grating, and the grating depth is linearly increased from top to bottom and from 40nm to 150 nm.

Preferably, the incoupling grating is a slanted grating, the slant angle being between 5 and 50 degrees.

Preferably, the relay grating is a positive grating.

Preferably, the exit grating is a positive grating or a slanted grating.

Preferably, the included angle between the grating vector of the incoupling grating and the grating vector of the emergent grating is 80-120 degrees, and the grating vector of the relay grating is positioned on the angle bisector of the grating vector of the incoupling grating and the grating vector of the emergent grating.

Preferably, the polymer substrate is PMMA polymethyl methacrylate with good visible light transmittance, PC polycarbonate, CR39 epoxy resin, PS polystyrene, PEN polyethylene naphthalate or episulfide resin, the refractive index is between 1.5 and 1.9, and the thickness is between 0.3mm and 1.5 mm.

Preferably, the functional film is a photo-curable or a thermosetting resin having a refractive index of 1.5 to 1.9.

Preferably, the pitch between the resin holographic waveguide lens units corresponding to different wavelengths, i.e., different colors of light, is 5 to 100 micrometers.

Preferably, an antireflection film for improving the coupling efficiency of the image light into the resin holographic waveguide lens unit of the next layer is arranged in the coupling-in functional area.

Preferably, the light-curable resin is monofunctional or multifunctional monomer containing double or triple bond of epoxy acrylate, urethane acrylate, polyester acrylate, polyether acrylate, acrylated polyacrylic resin and unsaturated polyester, episulfide resin, or acrylate.

Preferably, the thermosetting resin is: the solid resin is prepared by mixing and reacting hydroxyl-containing resin or epoxy-containing resin and isocyanate or amino resin.

Preferably, the functional film also contains a photosensitizer which generates free radicals under the action of photons to initiate room-temperature oligomer polymerization and crosslinking.

Preferably, the distance between the bottom of the nano-diffraction grating on the functional film and the upper surface of the polymer substrate is any value other than 0 between 0 and 20 micrometers.

The invention also provides a method for preparing a resin holographic waveguide lens, comprising the following steps:

s1: parameter calculation, namely determining the period, orientation and depth distribution of the nanometer diffraction grating in the coupling-in functional area, the relay functional area and the emergence functional area and waveguide parameters of the resin holographic waveguide lens according to light with the wavelength required to be regulated and controlled and an AR optical path imaging field angle;

s2: preparing a template, namely manufacturing the template (mother board) by utilizing a photoetching process or mechanical precision machining. According to the requirement, one or more times of plate transfer can be carried out;

s3: firstly, coating a functional film on a polymer substrate, and manufacturing a coupling-in functional area, a relay functional area and an emitting functional area on the functional film by a nano-imprinting technology.

Preferably, step S2 is: and (3) spin-coating a photoresist on a quartz substrate, and performing photoetching by using interference light 1 and interference light 2 as a double-beam interference light source by using a laser as an interference photoetching light source.

In practical application, the thickness of the photoresist can be selected to be between 100nm and 500nm, and the laser wavelength of the helium cadmium laser is 193nm to 450nm, preferably 325 nm.

The preparation methods of the nanometer diffraction grating templates in the corresponding coupling-in functional area, the relay functional area and the emergence functional area are respectively as follows:

preparing a nanometer diffraction grating template in the coupling-in functional area, covering a photomask plate on a quartz substrate coated with photoresist, wherein only the coupling-in functional area is transparent, interference light 1 and interference light 2 are positioned at the same side of the normal of the quartz substrate, the interference light 1 and the normal of the quartz substrate form an angle of 10 degrees, and the interference light 2 and the normal of the quartz substrate form an angle of 49.2 degrees;

preparing a nanometer light diffraction grating template in a relay functional area, covering a photomask plate on a quartz substrate coated with photoresist, transmitting light only in the relay functional area, linearly increasing the transmittance of the light transmitting area from left to right corresponding to linear change of grating depth, wherein interference light 1 and interference light 2 are symmetrical to the normal of the quartz substrate, and the incident direction and the normal form an angle of 26.8 degrees;

the preparation of the nanometer diffraction grating template in the emergent functional area is characterized in that a quartz substrate coated with photoresist is covered with an optical mask plate, only the position of the emergent functional area is transparent, the transmittance of the transparent area is linearly increased from top to bottom, the depth of a corresponding grating is linearly changed, interference light 1 and interference light 2 are symmetrical to the normal of the quartz substrate, and the included angle between the interference light 1 and the normal is 18.6 degrees.

Preferably, step S3 is: firstly, dripping the episulfide-UV curing resin serving as a functional film on an episulfide-UV curing resin substrate, pressing the template prepared in the step S2 on the episulfide-UV curing resin, applying pressure on the episulfide-UV curing resin by using a roller to enable the episulfide-UV curing resin to be uniformly filled between the template and the polymer substrate, curing and uniformly exposing the episulfide-UV curing resin, forming the cured episulfide-UV curing resin into the functional film with the nanometer diffraction grating, and finally demoulding.

If necessary, the functional regions and the nano-diffraction gratings in the regions can also be directly manufactured on the polymer substrate by using a template through thermal nano-imprinting. The UV nanoimprint lithography method is characterized by adopting UV nanoimprint lithography to manufacture on the curable polymer, and the imprint process mode comprises flat-to-flat imprint lithography, roll-to-roll imprint lithography and roll-to-flat imprint lithography, so that the production efficiency is improved. The UV gluing mode comprises dispensing and screen printing (printing according to the shape of the lens). The template may be placed above or below the resin substrate.

Preferably, step S4 is further included after step S3: and manufacturing the high-refractive-index optical film on the surface of the nano diffraction grating subjected to nano imprinting.

Preferably, step S5 is further included after step S4: and stamping the polymer substrate imprinted with the nano diffraction grating into a resin holographic waveguide lens unit.

Preferably, step S6 is further included after step S5: and superposing the resin holographic waveguide lens units respectively corresponding to different primary colors into a resin holographic waveguide lens in an opposite position.

Preferably, in S1, the waveguide parameters of the resin holographic waveguide lens include the refractive index n1 and the thickness d of the polymer substrate, the refractive index n2 of the functional thin film, and the distance h from the bottom of the nano-diffraction grating to the upper surface of the polymer substrate.

In S2, the lithography process includes electron beam lithography, interference lithography, deep (extreme) uv lithography, deep (uv pixel interference direct writing, and other common techniques for manufacturing sub-wavelength gratings. The material can be photoresist, PMMA, PS and other organic materials, can be directly operated on quartz and other inorganic substrates, or can be directly obtained on nickel and other metal substrates.

In S2, the plate transferring method includes micro-electroforming, flexible transfer, and nano-imprinting, and may also include etching techniques such as reactive ion etching and inductive ion etching.

In S2, the transfer material used for manufacturing the mold may be PET, PC, PDMS organic material, or quartz, silicon wafer inorganic material, or may be selected from metal materials such as nickel.

In S2, the three grating function areas of the lens can be obtained by the same process or different processes. If the former is adopted, the plate can be formed at one time during plate transfer; if the grating is the latter, the gratings with different structural depths and shapes prepared by different methods need to be combined on the same piece of mould.

In S3, the method can be performed by thermal nanoimprinting directly on the polymer substrate, or by UV nanoimprinting on the curable polymer, and the imprint process includes flat-to-flat imprint, roll-to-roll imprint, and roll-to-flat imprint, so as to improve the production efficiency. The UV gluing mode comprises dispensing and screen printing (printing according to the shape of the lens). The mold may be placed above or below the resin substrate.

In S4, the high refractive index optical film may be prepared by magnetron sputtering, chemical vapor deposition, thermal evaporation, or the like.

In S5, the resin lens is press-molded according to the shape of the desired lens. And multiple resin lenses are superposed, and alignment calibration is required. The space between the lenses can be controlled by organic or inorganic films with high transmittance, proper selective reflection increasing is carried out, coupling efficiency is improved, and frame sealing glue is adopted for packaging.

The invention also provides a three-dimensional display device which comprises the resin holographic waveguide lens and an image generation device.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed to be used in the description of the embodiments of the present invention will be briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art that other drawings can be obtained according to these drawings without creative efforts.

FIG. 1 shows the basic structure of a preferred embodiment of the resin holographic waveguide lens of the present invention for enhancing a display device;

FIGS. 2a and 2b are structural diagrams of a diffraction grating with a structure scale in nanometer scale in XY and XZ planes;

FIG. 2c1 is a schematic diagram of the period, width, height and tilt angle of a nanometer diffraction grating coupled into a functional region;

FIG. 2c2 is a schematic view of the incoupling functionality being processed directly on the polymer substrate;

FIG. 2c3 is a schematic view of a coupling-in functional region formed on a functional film;

FIG. 2d1 is a schematic diagram of the period, width and height of the nanometer diffraction grating of the relay and exit functional region;

FIG. 2d2 is a schematic view of the relay, exit functionality area being fabricated directly on the polymer substrate;

FIG. 2d3 is a schematic view of the relay and exit functional regions formed on the functional film;

FIG. 3 is a schematic view of a resin holographic waveguide lens having a coupling-in functional region, a relay functional region and an exit functional region at the same time;

FIG. 4 is a schematic diagram of the operation of a three-dimensional display device constructed using resin holographic waveguide lenses;

FIG. 5 is a schematic diagram of a method for making a red holographic lens template corresponding to red light;

FIG. 6a is a schematic diagram of a nano-diffraction grating template processed by photolithography, and FIG. 6b is a schematic diagram of a nickel template structure;

FIG. 7 is a schematic view of a resin holographic waveguide lens manufactured by nanoimprint lithography;

FIG. 8 is a schematic view of a nano-diffraction grating with a high refractive index dielectric film coated on the surface;

FIG. 9 is a schematic view showing one-step molding of a resin holographic waveguide lens using a press grinder;

FIG. 10 is a schematic diagram of a resin holographic waveguide lens with color development formed by stacking three pieces of resin holographic waveguide lens units corresponding to red, green and blue three primary colors.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

the functional region is arranged on the polymer substrate;

FIG. 1 shows the basic structure of a preferred embodiment of the resin holographic waveguide lens of the present invention for enhancing a display device. The device comprises a miniature image source, a projection optical system and a resin holographic waveguide lens. Light emitted by an image source is coupled into a waveguide (polymer substrate) prepared by resin materials from the coupling-in functional area of the resin holographic waveguide lens after passing through a projection optical system. After diffraction, the light is diffused to a relay functional area, the light propagation angle meets the total reflection condition, each time the light acts on the surface of the grating, partial energy is diffracted, and the rest energy continues to propagate. After passing through the relay functional area, the image is widened in the x direction, the propagation direction is changed at the same time, the image is coupled to the emergent functional area, the total reflection condition of the waveguide is continuously met, similarly, each time the light and the grating surface act, part of light energy is diffracted and emitted, and the image is widened in the Y direction. After the nano diffraction grating in the functional region is emitted, the image is coupled and output to glasses of an observer, and the image is widened in the XY directions, so that the whole image can be seen by human eyes in a larger region, and the use comfort and the applicable crowd range of the device are improved.

The invention adopts the principle based on physical optics and diffraction optics, and the resin holographic waveguide lens consists of two parts, wherein one part is an optical waveguide prepared by resin materials, namely a polymer substrate, and the other part is a functional film and a nanometer diffraction grating arranged on the functional film and is used for optical path folding and imaging. A single nanostructured grating interacts with light to change its phase. Referring to fig. 2a and 2b, fig. 2a and 2b are structural views of a diffraction grating having a structure scale in the nanometer scale in the XY plane and the XZ plane. According to the grating equation, the period and the orientation angle of the diffraction grating pixel satisfy the following relations:

(1)tanφ₁＝sinφ/(cosφ-n sinθ(Λ/λ))

(2)sin²(θ₁)＝(λ/Λ)²+(n sinθ)²-2n sinθcosφ(λ/Λ)

wherein, the light (in the three-dimensional display device, the light refers to the image information beam generated by the image generating device such as the micro projection device) is incident on the XY plane at a certain angle, θ 1 and Φ 1 sequentially represent the diffraction angle of the diffracted light (the angle between the diffracted light and the positive direction of the z axis) and the azimuth angle of the diffracted light (the angle between the diffracted light and the positive direction of the x axis), θ and λ sequentially represent the incident angle (the angle between the incident light and the positive direction of the z axis) and the wavelength of the light source 201, Λ and Φ sequentially represent the period and the orientation angle of the nano diffraction grating 101 (the angle between the groove direction and the positive direction of the y axis), and n represents the refractive index of the light wave in the medium.

Fig. 2c1 is a schematic diagram of the period a, width W, height h, and tilt angle α of a nano-diffraction grating coupled into a functional region, if a positive grating is used, α is 90 °.

Fig. 2c2 is a schematic view of the incoupling functional region 201 being processed directly on the polymer substrate 2.

Fig. 2c3 is a schematic view of the coupling-in functional area 201 being processed on the functional film 21 (in some embodiments, the material of the functional film is UV curable resin, and in this document, the reference numeral 21 is also used). The distance from the bottom of the nano diffraction grating to the upper surface of the polymer substrate 2 is d.

Fig. 2d1 is a schematic diagram of the period a, width W, height h of the nano-diffraction grating of the relay and exit functional regions.

Figure 2d2 is a schematic view of the relay, exit functionality area being fabricated directly on the polymer substrate.

FIG. 2d3 is a schematic view of the relay and exit functional regions formed on the functional film 21; the distance from the bottom of the nano diffraction grating to the upper surface of the polymer substrate 2 is d.

In some embodiments, as shown in fig. 3, for a schematic view of a resin holographic waveguide lens having a coupling-in functional region, a relay functional region and an exit functional region, the coupling-in functional region 201 is configured as a rectangle (which may be configured as a square if necessary) close to a square with a nano-diffraction grating, and couples external light into an optical waveguide 2 (i.e. a polymer substrate, or may be referred to as a resin body) made of a resin material, the coupling-in functional region is configured with a size according to an exit pupil size, such as a size of 4mmX4mm, in this embodiment, a groove direction of the nano-diffraction grating is parallel to a y axis, so that the light coupled into the optical waveguide 2 is transmitted in the X direction. The relay functional area 202 is in this example a rectangular grating provided with a nano-diffraction grating, the function of which is to guide the light guided by the coupling-in functional area from the X direction to the Y direction, the dimensions of which are set as required, in this example 4mm X3cm, the grooves of which nano-diffraction grating are at an angle of 45 degrees to the X axis. The exit functional region 203 is a large rectangle (a size may be a square with respect to the incoupling functional region) provided with a nano-diffraction grating, and functions to output the light guided by the relay functional region 202 to a space outside the optical waveguide 1, and to couple and output the light vertically to the human eye 1, and the size is set as required, and in this example, the size is 1.5cmX3 cm.

The distance between the three functional areas is set as required, and in the example of fig. 3, the distance between the coupling-in functional area 201 and the relay functional area 202 is 1.5mm, and the distance between the functional area 202 and the exit functional area 203 is 7 mm.

When a set of augmented reality three-dimensional display device is constructed, two sets of the resin holographic waveguide lenses are generally included and respectively correspond to left and right eyes for display.

In some embodiments, in order to implement color display, each set of resin holographic waveguide lens is composed of three resin holographic waveguide lens units, where the three resin holographic waveguide lens units respectively correspond to three colors of red, green, and blue (for a three-primary-color system, if necessary, for a four-primary-color system, four resin holographic waveguide lens units may be used to respectively correspond to each primary color), and correspond to a 30-degree field angle.

In this example, for a red holographic lens, the incoupling functional area nano-diffraction grating period is 510nm, the nano-diffraction grating tilt angle can be 28 degrees using a slanted grating, and the nano-diffraction grating depth can be 300 nm. The period of the relay functional area nanometer diffraction grating is 360nm, a positive grating is adopted, and the grating depth is linearly increased from left to right and from 40nm to 100 nm. The period of the nano diffraction grating in the outgoing functional area is 510nm, a positive grating is adopted, and the grating depth is linearly increased from top to bottom and from 40nm to 150 nm. For the green holographic lens, the period of the nanometer diffraction grating in the coupling functional area is 440nm, a slant grating is adopted, the slant angle of the grating is 23 degrees, and the depth of the grating is 250 nm. The period of the relay functional area nanometer diffraction grating is 310nm, a positive grating is adopted, and the grating depth is linearly increased from left to right and from 30nm to 90 nm. The period of the nano diffraction grating in the outgoing functional area is 440nm, a positive grating is adopted, and the grating depth is linearly increased from top to bottom and from 30nm to 130 nm. For the blue holographic lens, the period of the nanometer diffraction grating in the coupling functional area is 370nm, a slant grating is adopted, the slant angle of the grating is 18 degrees, and the depth of the grating is 200 nm. The period of the relay functional area nano compression grating is 260nm, a positive grating is adopted, and the grating depth is linearly increased from left to right and from 20nm to 70 nm. The period of the outgoing functional area nanometer diffraction grating is 370nm, the grating is a positive grating, and the grating depth is linearly increased from top to bottom and from 20nm to 100 nm.

The polymer substrate of the single resin holographic waveguide lens unit can adopt episulfide resin, the thickness can be set according to requirements, such as any value between 0.3mm and 1.5mm (inclusive), such as 0.8mm, and the distance between the lower surface of the nanometer diffraction grating groove and the upper surface of the polymer substrate can be any value between 0 micrometer and 20 micrometer, which is not 0, such as 500 nm.

Fig. 4 is a schematic diagram showing the operation of constructing a three-dimensional display device by using a resin holographic waveguide lens, wherein a light emitting point on an image source 101 (an image generating device) is collimated into parallel light after passing through an optical system 102 (a lens device), and the parallel light is incident on a nano diffraction grating coupled into a functional area 201 to be diffracted, and the positive first-order transmitted diffracted light meets the total reflection condition of the waveguide and is transmitted in an optical waveguide 2. Because of the inclined grating, the intensity of the symmetrical negative first-order diffraction light is very weak, and most energy is diffracted to transmit the positive first-order. Therefore, the coupling-in efficiency of the nano diffraction grating in the coupling-in functional area can reach 80% at the corresponding wavelength position. The positive first order diffracted light is coupled into the optical waveguide 2, propagates in the optical waveguide 2 by total reflection, and first reacts with the relay functional region 202, and the propagation plane is changed from the XZ plane to the YZ plane, so that the image is widened in the X direction. The propagation angle is unchanged, the total reflection condition is still met, the optical waveguide 2 continues to propagate in a total reflection mode, the optical waveguide 2 acts with the nanometer diffraction grating of the emergent functional area 203, image information is coupled out of the optical waveguide 2 through reflection diffraction, the optical waveguide is widened in the Y direction, and the human eyes can see images in the range of 1.5cm multiplied by 3cm, so that the observation comfort is improved, and the range of applicable people is enlarged. Because the depths of the nanometer diffraction gratings of the relay functional area 202 and the emergent functional area 203 are gradually distributed along with the space, the intensity of the image emergent from the resin holographic waveguide lens is uniform in the whole observation range.

In some embodiments, the resin holographic waveguide lens can be selectively projected, and the nanometer diffraction grating and the functional film are positioned on a coupling-in surface; or the resin holographic waveguide lens is in a selective reflection type, and the nanometer diffraction grating and the functional film are positioned opposite to the coupling-in surface; the depth of the nanometer diffraction grating arranged on the reflection type resin waveguide lens is equal to or close to half of the depth of the nanometer diffraction grating arranged on the transmission type resin holographic waveguide lens.

In practical application, the resin holographic waveguide lens can be formed by adopting a single-chip resin holographic waveguide lens unit and is used for constructing a required three-dimensional display device or used as an optical component for production, sale and application in product construction, and the resin holographic waveguide lens can also be formed by overlapping two, three or more than three resin holographic waveguide lens units; the nano diffraction gratings in the functional areas on different resin holographic waveguide lens units correspondingly regulate and control optical signals with different wavelengths, namely the nano diffraction gratings in the functional areas on different resin holographic waveguide lens units have different periods and different arrangements. Thereby, color display can be conveniently realized.

For example, in a three-primary-color display system, the period of the coupled grating is 290nm to 410nm and the grating depth is 100nm to 500nm corresponding to the nanometer diffraction grating on the resin holographic waveguide lens unit for regulating and controlling blue light; the period of the relay grating is between 200nm and 290nm, and the depth of the grating is between 30nm and 300 nm; the period of the outgoing grating is consistent with that of the incoming grating, and the depth is between 30nm and 300 nm.

The period of the coupled grating is between 350nm and 480nm, and the depth of the grating is between 100nm and 600 nm; the period of the relay grating is between 250nm and 335nm, and the depth of the grating is between 30nm and 350 nm; the period of the outgoing grating is consistent with that of the incoming grating, and the depth is between 30nm and 400 nm.

Preferably, the relay grating is a positive grating, and the grating depth is linearly increased from 30nm to 90hm from left to right.

The period of the coupled grating is between 415nm and 550nm, and the grating depth is between 100nm and 800 nm; the period of the relay grating is between 295nm and 390nm, and the grating depth is between 40nm and 400 nm; the period of the outgoing grating is consistent with that of the incoming grating, and the depth is between 30nm and 400 nm.

The coupling-in grating on the resin holographic waveguide lens unit corresponding to each primary color is an inclined grating, and the inclination angle is between 5 and 50 degrees. To improve the light coupling efficiency.

The emergent grating can be a positive grating or a tilted grating.

The depths of the relay grating and the emergent grating are linearly and gradually distributed along with the space change according to the total reflection coupling-in light intensity at each time, so that uniform emergent light is realized.

The selection of the parameters, the foregoing example, gives a specific combination of parameters, and in practical applications, the matching and the selection are performed in the above range according to practical requirements.

In practical applications, the polymer substrate may be made of PMMA polymethylmethacrylate, PC polycarbonate, CR39 epoxy resin, PS polystyrene, PEN polyethylene naphthalate, or episulfide resin with good visible light transmittance, and the refractive index is between 1.5 and 1.9, preferably a material with a refractive index greater than or equal to 1.7, and the thickness is selected from 0.3mm to 1.5 mm.

The present invention also provides a method for preparing a resin holographic waveguide lens, comprising the steps of:

s2: preparing a template, namely making a master plate by utilizing a photoetching process, and performing one-time or multiple-time plate transfer;

Preferably, as shown in fig. 5, step S2 is: a positive photoresist 8 is spin-coated on a quartz substrate 7, the thickness is 350nm, a helium cadmium laser with the wavelength of 325nm is used as an interference photoetching light source, and double-beam interference light of interference light 1 and interference light 2 is used for photoetching;

preparing a nanometer diffraction grating template in the coupling-in functional area, covering a photomask plate 9 on a quartz substrate coated with photoresist, transmitting light only in the coupling-in functional area, wherein interference light 1 and interference light 2 are positioned on the same side of the normal of the quartz substrate, the interference light 1 and the normal of the quartz substrate form an angle of 10 degrees, and the interference light 2 and the normal of the quartz substrate form an angle of 49.2 degrees;

preparing a nanometer light diffraction grating template in a relay functional area, covering a photomask plate 9 on a quartz substrate 7 coated with photoresist 8, transmitting light only in the relay functional area, linearly increasing the transmittance of the light transmitting area from left to right, linearly changing the depth of a corresponding grating, and making interference light 1 and interference light 2 symmetrical to the normal of the quartz substrate, wherein the incident direction and the normal form an angle of 26.8 degrees;

a nanometer diffraction grating template in an emergent functional area is prepared by covering a quartz substrate 7 coated with photoresist 8 with a photomask plate 9, wherein only the position of the emergent functional area is light-transmitting, the transmittance of the light-transmitting area is linearly increased from top to bottom, the depth of a corresponding grating is linearly changed, interference light 1 and interference light 2 are symmetrical to the normal of the quartz substrate, and the included angle between the interference light 1 and the normal is 18.6 degrees.

Preferably, step S3 is: firstly, dripping episulfide UV curing resin serving as a functional film on an optical-grade polymer substrate, pressing the template prepared in the step S2 on the episulfide UV curing resin, applying pressure on the episulfide UV curing resin by using a roller to enable the episulfide UV curing resin to be uniformly filled between the template and the polymer substrate, curing the episulfide UV curing resin, uniformly exposing, forming the functional film with the nanometer diffraction grating by the cured episulfide UV curing resin, and finally demolding.

Taking the preparation method of the resin holographic waveguide lens unit corresponding to red light as an example, a red holographic lens template is prepared first, as shown in fig. 5, the manufacturing processes of the green and blue lens templates are similar and will not be repeated. A positive photoresist 8 is spin coated on a quartz substrate 7 to a thickness of between 100nm and 500nm, in this example around 350 nm. The wavelength of the laser is 193nm to 450nm, a helium cadmium laser with the wavelength of 325nm is used as an interference photoetching light source in the present example, for the manufacture of the grating of the coupling-in functional area, the interference light 1 and the interference light 2 are positioned at the same side of the normal line of the quartz substrate, the interference light 1 and the normal line of the quartz substrate form 10 degrees, the interference light 2 and the normal line of the quartz substrate form 49.2 degrees, a photomask plate 9 is covered on the quartz substrate 7 coated with the photoresist 8, only the coupling-in functional area transmits light, and the exposure time is controlled. And in the second exposure, a photomask plate with the same shape as the relay functional area is adopted, but the transmittance of the light transmission area is different, and the transmittance is linearly increased from left to right and linearly changes corresponding to the grating depth. In this case, the interference light 1 and the interference light 2 are symmetrical to the normal of the quartz substrate, and the incidence direction and the normal form 26.8 degrees, and the exposure time is controlled. For the third exposure, a photomask with the same shape as the exit functional region is adopted, but the transmittance of the light transmission region of the photomask is different, and from top to bottom, the transmittance increases linearly, and the linear change of the grating depth is shown in fig. 6a and 6b, wherein fig. 6a shows that the required grating is processed on the photoresist 8 by using the photolithography technology, and then the corresponding nickel template 81 is correspondingly manufactured, as shown in fig. 6 b. The

interference light

1 and 2 is now symmetrical about the normal to the quartz substrate and makes an angle of 18.6 with the normal. The exposure of the three times of exposure procedures needs to be matched, the exposure and the development conditions need to be optimized, the development rate and the exposure are in a linear relation, and after development, the depth of the nanometer diffraction gratings in the three functional areas in the photoresist is slightly larger than the design depth. The pattern on the photoresist is transferred to a nickel stamp 81 by electroforming, as shown in fig. 6a and 6b, by procedures including cleaning, immersion silver, nickel growth, stripping, cleaning. The nickel template grown at one time can be directly used for manufacturing the resin holographic waveguide lens through nanoimprint lithography, and also can be used for manufacturing a plurality of nickel templates 81 through plate turning, so that the cost is reduced. Figure 6b shows a schematic of the structure of a nickel template 81 with a grating shape complementary to the grating shape in the photoresist of figure 5.

Fig. 7 is a schematic diagram illustrating a resin holographic waveguide lens manufactured by nanoimprint lithography, in this embodiment, a flat-to-flat nanoimprint lithography method is adopted, firstly, an appropriate amount of episulfide UV curing resin 21 having a high refractive index is dripped on episulfide resin (as a polymer substrate 2, i.e., as a resin body of a waveguide), which facilitates to improve coupling efficiency of the entire holographic waveguide lens, and simultaneously facilitates to make light in the entire field angle satisfy a total reflection condition, the thickness of the episulfide resin substrate (polymer substrate 2) is 0.8mm, the nickel template 81 in fig. 6b is pressed on the episulfide resin coated with UV curing resin 21, and pressure is applied thereto by a roller to make the UV curing resin 21 uniformly fill between the nickel template 81 and the episulfide resin substrate, the distance from the bottom of a grating groove to the upper surface of the episulfide resin becomes a residual layer thickness after imprinting, which is 500nm in this embodiment, which can be controlled to any value other than 0 to 20 μm as required, the thickness is controlled to be any value other than 0 μm when the coating amount of UV curing resin 21 is imprinted and the grating groove is applied, the grating groove is not directly exposed, the UV curing resin 81, the UV curing resin is controlled by a small UV exposure amount of the UV curing resin, and the UV curing resin is controlled by a small UV exposure intensity of L, and the UV curing resin is controlled by UV curing resin, and the UV curing resin, and the UV curing resin is controlled by UV resin, and the UV curing resin film is controlled by the UV curing resin.

As shown in fig. 8, after the nano diffraction gratings in the three functional areas are transferred to the UV curing resin 21 to form a functional thin film, a high refractive index dielectric layer 211 is prepared on the surface of the nano diffraction grating, and in this embodiment, a magnetron sputtering process is adopted, and a 50nm titanium dioxide layer is sputtered on the surface of the UV curing resin 21 to improve the coupling efficiency of the whole lens. The high-refractive-index dielectric layer 211 does not affect the transmittance of the lens, and meanwhile, the magnetron sputtering process is matched with the roll-to-roll process, so that the lens has the advantages of high production efficiency and low cost.

Fig. 9 shows a resin hologram waveguide lens formed in one step by a press mold 83. Manufacturing a stamping die 83 according to the shape and the size of the needed lens, fixing the episulfide resin 2 imprinted with the nano diffraction grating on a punch press or a pressing machine, and applying a certain pressure to the episulfide resin 2 imprinted with the nano diffraction grating by using the stamping die 83 to cut and separate episulfide resin materials, thereby obtaining the episulfide resin lens, namely the resin holographic waveguide lens unit which meets certain size requirements and appearance quality. The conventional glass holographic waveguide lens has the advantage of high flatness, but each glass is polished by a conventional optical processing method, so that the efficiency is low and the cost is high. The resin lens is quickly molded by utilizing the offset die, and the method has the advantages of high production efficiency, stable product quality, qualified precision and high material utilization rate. The red, green and blue three-resin holographic waveguide lens unit is manufactured through the processes, and comprises photoresist pattern manufacturing, nickel template pattern transfer, UV nanoimprint, high-refractive-index optical layer manufacturing and offset mold forming. After the template is manufactured, subsequent production and replication operations including UV nanoimprint, high-refractive-index optical layer and offset mold forming are all suitable for roll-to-roll or roll-to-flat mass production. In the step of writing the grating structure into the photoresist, an alignment mark can be added in a proper area, and after the production by duplication, the alignment mark exists on each lens, so that three resin holographic waveguide lens units respectively corresponding to red, green and blue primary colors can be conveniently aligned and superposed in the follow-up process. As shown in fig. 10, three resin holographic

waveguide lens units

001, 002, 003 of blue, green, and red are stacked together by using alignment marks, from top to bottom, the three resin holographic

waveguide lens units

001, 002, 003 of blue, green, and red may be respectively, the distance between the resin holographic waveguide lens units 00I/002/003 is 0.1mm, or may be set to other pitches as required, the resin holographic

waveguide lens units

001, 002, 003 of blue, green, and red are bonded together by frame sealing glue, and the distance between the resin holographic

waveguide lens units

001, 002, 003 of blue, green, and red is controlled by the thickness of the frame sealing glue. The image light is introduced from the coupling-in functional region of the upper blue resin hologram waveguide lens unit 001 (resin hologram waveguide lens unit corresponding to blue light, and the lower green lens and red lens are resin hologram waveguide lens units corresponding to green light and red light, respectively), and light in the blue wavelength band is coupled into the first resin hologram waveguide lens unit, and due to the wavelength selectivity of the grating, light of other wavelengths has low diffraction efficiency in the coupling-in functional region of the blue lens, and is concentrated in 0-order light and continues to propagate downward. And the light of the similar green wave band is coupled into the second resin holographic waveguide lens unit when the light reaches the coupling-in functional area of the green resin holographic waveguide lens unit 002, and the light of the residual red wave band continues to propagate downwards and is finally coupled into the third resin holographic waveguide lens unit by the coupling-in functional area of the red resin holographic waveguide lens unit 003. In order to reduce the reflectivity of light at different interfaces and improve the light energy utilization rate, an anti-reflection layer is added at the coupling-in functional area positions of the blue resin holographic waveguide lens unit 001 and the green resin holographic waveguide lens unit 002, and the green resin holographic waveguide lens unit 002 and the red resin holographic waveguide lens unit 003, the anti-reflection layer can still be made of an episulfide resin material or other materials meeting the requirements, the thickness can be selected to be 100 micrometers or other values, and the film is required to be coated, so that the anti-reflection effect is achieved. After the three resin holographic waveguide lens units of blue, green and red are stacked together, the three resin holographic waveguide lens units can be placed in an imaging light path, and finally the augmented reality three-dimensional display device is realized.

The invention also provides a three-dimensional display device which comprises the resin holographic waveguide lens and an image generation device. The related technical solutions of how the image generation device and the waveguide lens construct the three-dimensional display device have been described in the prior patents and the prior art, and are not described again.

The embodiments in the present description are described in a progressive manner, each embodiment focuses on differences from other embodiments, and similar parts between the embodiments are referred to each other. The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A resin holographic waveguide lens is characterized by comprising one or more resin holographic waveguide lens units;

the resin holographic waveguide lens unit comprises a polymer substrate and a functional area, wherein the functional area comprises a coupling-in functional area, a relay functional area and an emergent functional area, and a nano diffraction grating is arranged in the functional area; the distance between the bottom of the nanometer diffraction grating and the surface of the polymer substrate is more than 0;

the nanometer diffraction gratings in the coupling-in functional area, the relay functional area and the emergence functional area are respectively coupling-in gratings for coupling external light beams into the resin holographic waveguide lens, relay gratings for changing the propagation direction of the light beams in the resin holographic waveguide lens and emergence gratings for outputting the light beams propagated from the resin holographic waveguide lens to the outside of the resin holographic waveguide lens;

the relay grating is a positive grating, and the grating depth is linearly increased from left to right; the emergent grating is a positive grating, and the grating depth is increased linearly from top to bottom; the grating vector of the relay grating is positioned on an angle bisector of the coupled grating vector and the emergent grating vector; the included angle between the coupled grating vector and the emergent grating vector is between 80 degrees and 120 degrees;

the functional region is arranged on the polymer substrate;

2. The resin holographic waveguide lens of claim 1, wherein the surface of the nano diffraction grating is provided with an antireflection film.

3. The resin holographic waveguide lens of claim 1, wherein the resin holographic waveguide lens is transmissive, the nano-diffraction grating is located at a coupling-in surface; or the resin holographic waveguide lens is in a reflection type, and the nanometer diffraction grating is positioned opposite to the coupling-in surface; the depth of the nanometer diffraction grating arranged on the reflection type resin holographic waveguide lens is equal to half of the depth of the nanometer diffraction grating arranged on the transmission type resin holographic waveguide lens.

4. The resin holographic waveguide lens of claim 1, wherein the resin holographic waveguide lens is formed by stacking two or more resin holographic waveguide lens units; the nano diffraction gratings in the functional areas on different resin holographic waveguide lens units correspondingly regulate and control optical signals with different wavelengths, namely the nano diffraction gratings in the functional areas on different resin holographic waveguide lens units have different periods and different arrangements.

5. The resin holographic waveguide lens of claim 4, wherein, corresponding to the nanometer diffraction grating for regulating blue light, the period of the coupled grating is 290nm to 410nm, and the grating depth is 100nm to 500 nm; the period of the relay grating is between 200nm and 290nm, and the depth of the grating is between 30nm and 300 nm; the period of the outgoing grating is consistent with that of the incoming grating, and the depth is between 30nm and 300 nm.

6. The resin holographic waveguide lens of claim 4, wherein, corresponding to the nano diffraction grating for regulating green light, the period of the coupled grating is between 350nm and 480nm, and the grating depth is between 100nm and 600 nm; the period of the relay grating is between 250nm and 335nm, and the depth of the grating is between 30nm and 350 nm; the period of the outgoing grating is consistent with that of the incoming grating, and the depth is between 30nm and 400 nm.

7. The resin holographic waveguide lens of claim 4, wherein, corresponding to the nano diffraction grating for modulating red light, the period of the in-coupling grating is between 415nm and 550nm, and the grating depth is between 100nm and 800 nm; the period of the relay grating is between 295nm and 390nm, and the grating depth is between 40nm and 400 nm; the period of the outgoing grating is consistent with that of the incoming grating, and the depth is between 30nm and 400 nm.

8. The resin holographic waveguide lens of claim 5, wherein the relay grating is a positive grating with a linear increasing grating depth from left to right and from 30nm to 70 nm.

9. The resin holographic waveguide lens of claim 5, wherein the exit grating is a positive grating, and the grating depth increases linearly from top to bottom from 30nm to 100 nm.

10. The resin holographic waveguide lens of claim 6, wherein the relay grating is a positive grating with a linear increasing grating depth from left to right and from 30nm to 90 nm.

11. The resin holographic waveguide lens of claim 6, wherein the exit grating is a positive grating, and the grating depth increases linearly from top to bottom from 30nm to 130 nm.

12. The resin holographic waveguide lens of claim 7, wherein the relay grating is a positive grating with a linear increasing grating depth from left to right and from 40nm to 100 nm.

13. The resin holographic waveguide lens of claim 7, wherein the exit grating is a positive grating, and the grating depth increases linearly from top to bottom from 40nm to 150 nm.

14. The resin holographic waveguide lens of any one of claims 3 to 13, wherein the incoupling grating is a slanted grating, the slanted angle being between 5 degrees and 50 degrees.

15. The resin holographic waveguide lens of any of claims 1 to 13, wherein the functional film is a photo-cured or thermal-cured resin having a refractive index of between 1.5 and 1.9.

16. The resin holographic waveguide lens of any one of claims 4 to 13, wherein a pitch between the resin holographic waveguide lens units corresponding to different wavelengths, i.e., different colors of light, is 5 to 100 micrometers.

17. The resin holographic waveguide lens of any one of claims 4 to 13, wherein the functional film further comprises a photosensitizer capable of generating free radicals under the action of photons to initiate room temperature oligomer polymerization and crosslinking.

18. A method for preparing the resin holographic waveguide lens of any one of claims 1 to 17,

comprises the following steps:

s2: preparing a template, namely manufacturing the template by utilizing a photoetching process or mechanical precision machining;

s3: firstly, dripping the episulfide UV curing resin serving as a functional film on an episulfide resin substrate, pressing the template prepared in the step S2 on the episulfide UV curing resin, applying pressure on the episulfide UV curing resin by using a roller to ensure that the episulfide UV curing resin is uniformly filled between the template and the polymer substrate, then curing and uniformly exposing the episulfide UV curing resin, forming the functional film with the nanometer diffraction grating by the cured episulfide UV curing resin, finally demoulding, and carrying out one-step molding on the resin holographic waveguide lens by using a stamping die.

19. The method for producing a resin holographic waveguide lens of claim 18, wherein the step S2 is: a photoresist is spin-coated on a quartz substrate, and photolithography is performed with interference light 1 and interference light 2 as two beams of interference light.

20. The method for manufacturing a resin holographic waveguide lens according to claim 19, wherein the nano diffraction grating templates corresponding to the incoupling functional area, the relay functional area and the exit functional area are manufactured by the following methods, respectively, in step S2:

preparing a nanometer light diffraction grating template in a relay functional area, covering a photomask plate on a quartz substrate coated with photoresist, transmitting light only in the relay functional area, increasing the transmittance of the light transmitting area from left to right corresponding to the depth change of the grating, wherein interference light 1 and interference light 2 are symmetrical to the normal of the quartz substrate, and the incident direction and the normal form an angle of 26.8 degrees;

the preparation of the nanometer diffraction grating template in the emergent functional area is characterized in that a quartz substrate coated with photoresist is covered with an optical mask plate, only the position of the emergent functional area is light-transmitting, the transmittance of the light-transmitting area is increased from top to bottom corresponding to the depth change of the grating, and the interference light 1 and the interference light 2 are symmetrical by the normal line of the quartz substrate and form an included angle of 18.6 degrees with the normal line.

21. The method for producing a resin holographic waveguide lens of claim 20, further comprising step S4 after step S3: and manufacturing the high-refractive-index optical film on the surface of the nano diffraction grating subjected to nano imprinting.

22. A three-dimensional display device comprising a resin holographic waveguide lens according to any of claims 1 to 13, or a resin holographic waveguide lens prepared according to any of claims 19 to 21.