Two-dimensional vector holographic grating waveguide and manufacturing method thereof, and optical waveguide module

Abstract

The application relates to near-eye display technology, in particular to a two-dimensional vector holographic grating waveguide and a manufacturing method thereof and an optical waveguide module. The manufacturing method comprises the following steps: obtaining a two-dimensional diffraction efficiency matrix of the two-dimensional vector holographic grating waveguide at different propagation angles according to a formula group provided by the application, then obtaining a diffraction efficiency matrix of two one-dimensional gratings forming the two-dimensional vector holographic grating waveguide, and obtaining exposure energy required for manufacturing the two-dimensional vector holographic grating waveguide according to a linear relationship between the diffraction efficiency of the one-dimensional grating and exposure energy used when the grating is manufactured; and exposing a holographic plate to light by using the exposure energy, so as to obtain the two-dimensional vector holographic grating waveguide. The exposure energy of the two-dimensional vector holographic grating waveguide is optimized, and the optimized two-dimensional vector holographic grating waveguide is obtained. The method optimizes the exit pupil uniformity of the two-dimensional vector holographic grating waveguide, and improves the final eye-entrance display effect of the near-eye device.

Description

TECHNICAL FIELD

[0001] The present application relates to near-eye display technology, in particular to a two-dimensional vector volume holographic grating waveguide and a manufacturing method thereof, and an optical waveguide module. BACKGROUND

[0002] The holographic waveguide combines the total reflection characteristics of the waveguide and the diffraction characteristics of the holographic grating, can realize large field of view, large exit pupil image output, and the overall quality and volume are more compact. The holographic waveguide uses a reflective volume holographic grating as a coupling component, which can make the stray light less and the dispersion lower. The two-dimensional vector volume holographic waveguide technology further uses a two-dimensional vector reflective volume holographic grating as a coupling-out component, optimizes the current two-dimensional pupil expansion technology of three gratings (coupling-in grating, turning grating, coupling-out grating) in the industry, greatly saves the manufacturing time and cost of the holographic waveguide. At the same time, the optical machine can be made more light and compact, and the overall shape can be more suitable for the real glasses form, meeting various scene applications.

[0003] In the volume holographic waveguide, in order to obtain a larger exit pupil size, the light wave energy transmitted in the waveguide is divided into two parts in the coupling-out grating, part of the energy is coupled out, and the remaining part continues to be transmitted in the waveguide. The above process is repeated at different positions of the coupling-out grating to obtain a large-size exit pupil. Therefore, the local diffraction efficiency of the coupling-out grating needs to be optimized and designed to control the proportion of the output light intensity in the total output light intensity, so as to balance the output brightness of the entire exit pupil while expanding the exit pupil.

[0004] The related art research on the exit pupil uniformity of the volume holographic waveguide is only for one-dimensional gratings, and the related optimization design of the local diffraction efficiency of the two-dimensional vector volume holographic grating waveguide has not been involved. SUMMARY

[0005] In order to optimize the light output uniformity of the two-dimensional vector volume holographic grating waveguide, the present application provides a two-dimensional vector volume holographic grating waveguide and a manufacturing method thereof, and an optical waveguide module.

[0006] The manufacturing method of the two-dimensional vector volume holographic grating waveguide provided by the present application adopts the following technical scheme:

[0007] S1, obtain the two-dimensional diffraction efficiency matrix of the two-dimensional vector volume holographic grating waveguide at different propagation angles according to the following formula group, and then obtain the diffraction efficiency matrix of the two one-dimensional gratings forming the two-dimensional vector volume holographic grating waveguide, and obtain the exposure energy required for manufacturing the two-dimensional vector volume holographic grating waveguide according to the linear relationship between the diffraction efficiency of the one-dimensional grating and the exposure energy used when manufacturing the grating; the formula group is:

[0008]

[0009]

[0010]

[0011]

[0012] wherein, Angle t represents the propagation angle of the light wave in the two-dimensional vector volume holographic grating waveguide, m, n represents the transmission period of the light wave in the two-dimensional vector volume holographic grating waveguide at the propagation angle Angle t (1, 2, …T), represents the transmission intensity of the light wave in the two-dimensional vector volume holographic grating waveguide at the propagation angle Angle t (1, 2, …T), represents the coupling-out light intensity of the light wave in each local area of the two-dimensional vector volume holographic grating waveguide at the propagation angle Angle t (1, 2, …T), represents the average value of the coupling-out light intensity of the light wave in each local area of the two-dimensional vector volume holographic grating waveguide at the propagation angle Angle t (1, 2, …T), represents the two-dimensional diffraction efficiency matrix of the two-dimensional vector volume holographic grating waveguide at the propagation angle Angle t (1, 2, …T); and a is the absorption rate of the volume holographic grating.

[0013] S2, exposing the holographic plate to the exposure energy to obtain the two-dimensional vector volume holographic grating waveguide.

[0014] By using the above technical solution, the exposure energy for manufacturing the two-dimensional vector volume holographic grating waveguide is calculated under the premise of balancing the output luminance of the entire exit pupil, so that the holographic plate is exposed to the exposure energy to obtain the optimized two-dimensional vector volume holographic grating waveguide. The method optimizes the exit pupil uniformity of the two-dimensional vector volume holographic grating waveguide and improves the final eye display effect of the near-eye device.

[0015] In an embodiment of the present application, the step of further obtaining the diffraction efficiency matrix of the two one-dimensional gratings forming the two-dimensional vector volume holographic grating waveguide comprises:

[0016] weighting and averaging the two-dimensional diffraction efficiency matrix at all propagation angles to obtain a two-dimensional diffraction efficiency matrix under a full field of view;

[0017] obtaining the diffraction efficiency matrix of the two one-dimensional gratings forming the two-dimensional vector volume holographic grating waveguide according to the two-dimensional diffraction efficiency matrix under the full field of view.

[0018] By adopting the technical scheme, the influence of a single or some fields of view on the whole field of view is weakened by means of weighted average, and the light emission uniformity of the whole field of view is further improved.

[0019] In an embodiment of the present application, the step of obtaining the diffraction efficiency matrices of the two one-dimensional gratings forming the two-dimensional vector holographic grating waveguide according to the two-dimensional diffraction efficiency matrix under the whole field of view comprises:

[0020] The diffraction efficiency matrices ξ1 and ξ2 of the two one-dimensional gratings forming the two-dimensional vector holographic grating waveguide are obtained according to the formula ξ = ξ1 + (1-ξ1)ξ2; wherein, ξ represents the two-dimensional diffraction efficiency matrix under the whole field of view, and ξ1 and ξ2 respectively represent the diffraction efficiency matrices of the two one-dimensional gratings forming the two-dimensional vector holographic grating waveguide, and ξ1 and ξ2 are transposed to each other.

[0021] In an embodiment of the present application, the step of obtaining the diffraction efficiency matrices of the two one-dimensional gratings forming the two-dimensional vector holographic grating waveguide further comprises:

[0022] The diffraction efficiency matrices ξ1 and ξ2 of the two one-dimensional gratings forming the two-dimensional vector holographic grating waveguide are obtained according to the formula The diffraction efficiency matrices ξ1 and ξ2 of the two one-dimensional gratings forming the two-dimensional vector holographic grating waveguide are obtained according to the formula t1 and ξ t2 ; wherein, ξ t1 and ξ t2 respectively represent the diffraction efficiency matrices of the two one-dimensional gratings forming the two-dimensional vector holographic grating waveguide, and ξ t1 and ξ t2 are transposed to each other.

[0023] The weighted average values of the ξ t1 under all propagation angles and the weighted average values of the ξ t2 under all propagation angles are obtained, and the diffraction efficiency matrices ξ1 and ξ2 of the two one-dimensional gratings forming the two-dimensional vector holographic grating waveguide are obtained.

[0024] By adopting the technical scheme, the influence of a single or some fields of view on the whole field of view is weakened by means of weighted average, and the light emission uniformity of the whole field of view is further improved.

[0025] In an embodiment of the present application, the step of exposing the holographic plate by using the exposure energy to obtain the two-dimensional vector holographic grating waveguide comprises:

[0026] The energy of the exposure light beam emitted by the exposure light source is adjusted, so that the exposure energy of the exposure light beam irradiated to the holographic plate is the exposure energy obtained according to the ξ1 or the ξ2. ​​

[0027] In an embodiment of the present application, the step of adjusting the energy of the exposure light beam emitted by the exposure light source so that the exposure energy of the exposure light beam irradiated to the holographic plate is the exposure energy obtained according to the ξ1 or the ξ2 comprises:

[0028] Adjusting the energy of the exposure light beam emitted by the exposure light source and / or adjusting the exposure time of the holographic plate.

[0029] Meanwhile, the present application also provides a two-dimensional vector holographic grating waveguide, which is optimized by using the manufacturing method of the two-dimensional vector holographic grating waveguide according to any one of the embodiments of the present application.

[0030] Correspondingly, the present application also provides an optical waveguide module, which comprises an optical machine and the two-dimensional vector holographic grating waveguide according to the embodiments of the present application.

[0031] In summary, the present application has the following beneficial technical effects:

[0032] By using the formula group provided by the present application, the exposure energy for manufacturing the two-dimensional vector holographic grating waveguide is calculated under the premise of balancing the output luminance of the entire exit pupil, so that the holographic plate is exposed by using the exposure energy, and the optimized two-dimensional vector holographic grating waveguide is obtained. The method optimizes the exit pupil uniformity of the two-dimensional vector holographic grating waveguide and improves the final eye-entering display effect of the near-eye device. BRIEF DESCRIPTION OF DRAWINGS

[0033] Figure 1 is the CV graph of the two-dimensional vector holographic grating waveguide in the central field of view in Embodiment 1 of the present application;

[0034] Figure 2 is the CV graph of the two-dimensional vector holographic grating waveguide in the left field of view in Embodiment 1 of the present application;

[0035] Figure 3 is the CV graph of the two-dimensional vector holographic grating waveguide in the right field of view in Embodiment 1 of the present application. DETAILED DESCRIPTION

[0036] The following will be described in detail with reference to the accompanying drawings. Figures 1-3 The present application will be further described in detail.

[0037] The embodiments of the present application disclose a two-dimensional vector holographic grating waveguide and a manufacturing method thereof, and an optical waveguide module.

[0038] For a one-dimensional grating, considering that there is absorption loss in the transmission of light waves in the grating, and for a specific grating material, the absorption rates of red light, green light and blue light are all constant α. Therefore, for a specific field of view, there is:

[0039]

[0040] wherein ξ l (l = 1, 2…L) represents the diffraction efficiency of each local region, represents the light wave intensity that continues to propagate after the lth diffraction, represents the intensity of the light wave of the lth region diffracted out of the waveguide by the grating.

[0041] By comparing the intensities of the diffracted light waves of two consecutive regions, the relationship between the diffraction efficiency ξ l+1 of the l+1th region grating and the diffraction efficiency ξ l of the lth region grating is:

[0042]

[0043] For the full field of view, if the light intensity of each coupling-out region is uniform, i.e., the standard deviation of the output light intensity diffracted by each local region at each different propagation angle is the smallest. That is,

[0044]

[0045] wherein, represents the average value of the light intensity of each local region diffracted out of the waveguide by the grating at the propagation angle Angle t (1, 2, …T), represents the light intensity of the lth region light wave diffracted out of the waveguide by the grating at the propagation angle Angle t (1, 2, …T), and L is the transmission period of the light wave in the grating at the propagation angle Angle t (1, 2, …T). And wherein,

[0046]

[0047] wherein is the diffraction efficiency of the local region of the grating at the propagation angle Angle t (1, 2, …T).

[0048] Correspondingly, for a two-dimensional vector holographic grating waveguide, corresponding to a specific field of view, assuming that the two-dimensional diffraction efficiency matrix of the volume holographic grating is ξ(m, n), the total light intensity coupled in is 1, the absorption loss of the volume holographic grating is considered, and the absorption rate is set to be α, then the light wave intensity I in (m, n) in the local region of the M*N waveguide is a function expression of:

[0049]

[0050] Wherein, m, n are transmission periods of light wave in two-dimensional vector holographic grating waveguide respectively.

[0051] The function expression of light intensity I dif (m, n) is:

[0052]

[0053] Further, the two-dimensional vector holographic grating waveguide is actually a full field case, that is, including a plurality of different propagation angles, and the different propagation angles correspond to different propagation periods in the waveguide, and the propagation of light wave in the waveguide is different. Therefore, for a two-dimensional vector holographic grating waveguide including T different propagation angles , the function expression of light intensity I propagated in the local area of M*N waveguide is:

[0054]

[0055] The function expression of light intensity I diffracted by the two-dimensional vector holographic grating waveguide from the local area of the waveguide is:

[0056] If the overall light output uniformity of the two-dimensional vector holographic grating waveguide is to be improved, that is, the standard deviation of the output light intensity diffracted by each local area under each different propagation angle needs to be minimized. That is

[0057]

[0058] Wherein, represents the average value of the light intensity coupled out by the two-dimensional vector holographic grating waveguide in each local area under the propagation angle Angle t (1, 2, …T).

[0059] When the standard deviation of the output light intensity diffracted by the two-dimensional vector holographic grating waveguide from each local area under each propagation angle is minimized, the light output uniformity of the two-dimensional vector holographic grating waveguide is optimal. Therefore, according to formulas (7) to (9), it is derived that the function expression of the diffraction efficiency matrix t of the local area of the two-dimensional vector holographic grating waveguide under the propagation angle Angle (1, 2, …T) is:

[0060]

[0061] When the two-dimensional vector holographic grating waveguide is formed by two one-dimensional gratings with their vectors being perpendicular to each other, the diffraction efficiency matrix of the two-dimensional vector holographic grating waveguide is also formed by the interaction of the diffraction efficiency matrices of the two one-dimensional gratings, and the two diffraction efficiency matrices satisfy the formula:

[0062] ξ = ξ1 + (1 - ξ1)ξ2 (11)

[0063] wherein, ξ is the diffraction efficiency matrix of the two-dimensional vector holographic grating waveguide, ξ1 and ξ2 are the diffraction efficiency matrices of the two one-dimensional gratings respectively, and ξ1 and ξ2 are transposed to each other. The diffraction efficiency matrix of the two-dimensional vector holographic grating waveguide obtained according to the formula (7) to (10) can be used to obtain the diffraction efficiency matrices of the two one-dimensional gratings according to the formula (11).

[0064] Embodiment 1

[0065] The embodiment provides a method for manufacturing a two-dimensional vector holographic grating waveguide, and the optimization method comprises the following steps:

[0066] In step S1, the two-dimensional diffraction efficiency matrix of the two-dimensional vector holographic grating waveguide at different propagation angles is obtained according to the following formula group, and then the diffraction efficiency matrices ξ1 and ξ2 of the two one-dimensional gratings forming the two-dimensional vector holographic grating waveguide are obtained, and the exposure energy required for manufacturing the two-dimensional vector holographic grating waveguide is obtained according to the linear relationship between the diffraction efficiency of the one-dimensional grating and the exposure energy used in the manufacturing of the grating; the formula group is as follows:

[0067]

[0068]

[0069]

[0070]

[0071] wherein, Angle t represents the propagation angle of the light wave in the two-dimensional vector holographic grating waveguide, m and n are the transmission periods of the light wave in the two-dimensional vector holographic grating waveguide at the propagation angle Angle t (1, 2, …T), represents the light intensity of the light wave propagating in the two-dimensional vector holographic grating waveguide at the propagation angle Angle t (1, 2, …T), represents the coupling-out light intensity of the light wave in each local area of the two-dimensional vector holographic grating waveguide at the propagation angle Angle t (1, 2, …T), represents the coupling-out light intensity of the light wave in each local area of the two-dimensional vector holographic grating waveguide at the propagation angle Angle t(1, 2, ..., T) represents the average intensity of the coupled light from the light wave in each local region of the two-dimensional vector volume holographic grating waveguide. In terms of communication, Angle t The two-dimensional diffraction efficiency matrix of a two-dimensional vector volume holographic grating waveguide in (1, 2, ..., T), where α is the absorptivity of the volume holographic grating.

[0072] In one embodiment, the step of obtaining the diffraction efficiency matrices ξ1 and ξ2 of the two one-dimensional gratings forming the two-dimensional vector volume holographic grating waveguide based on the two-dimensional diffraction efficiency matrices at different propagation angles includes:

[0073] The two-dimensional diffraction efficiency matrix under all propagation angles is weighted and averaged to obtain the two-dimensional diffraction efficiency matrix under the full field of view.

[0074] According to the formula ξ=ξ1+(1-ξ1)ξ2, the diffraction efficiency matrices ξ1 and ξ2 of the two one-dimensional gratings forming the two-dimensional vector volume holographic grating waveguide are obtained; where ξ represents the two-dimensional diffraction efficiency matrix under the full field of view, ξ1 and ξ2 represent the diffraction efficiency matrices of the two one-dimensional gratings forming the two-dimensional vector volume holographic grating waveguide, respectively, and ξ1 and ξ2 are transposes of each other.

[0075] In another embodiment, the step of obtaining the diffraction efficiency matrices ξ1 and ξ2 of the two one-dimensional gratings forming the two-dimensional vector volume holographic grating waveguide based on the two-dimensional diffraction efficiency matrices at different propagation angles includes:

[0076] According to the formula get The diffraction efficiency matrices ξ of the two corresponding one-dimensional gratings t1 and ξ t2 ; where ξ t1 and ξ t2 They represent the formation The diffraction efficiency matrices of the two one-dimensional gratings, ξ t1 and ξ t2 They are transposes of each other; for all propagation angles ξ t1 Perform a weighted average for ξ at all propagation angles. t2 By performing weighted averaging, the diffraction efficiency matrices ξ1 and ξ2 of the two one-dimensional gratings that form the two-dimensional vector volume holographic grating waveguide are obtained.

[0077] The transmission period corresponding to different transmission angles and the local area division in the two-dimensional vector holographic grating waveguide are different. For example, assuming that the transmission angle of the transmission light wave in the waveguide is between 43°-63.4°, the optical path length of the reflection is between 1.86-3.99 when the thickness of the waveguide is 1 mm. Assuming that the effective area size of the two-dimensional vector holographic grating waveguide is 23*23 mm, the transmission period corresponding to the transmission angle is between 6*6-12*12. Generally, the longest transmission period 12*12 is used to divide the local area diffraction efficiency of the two-dimensional vector holographic grating waveguide, so that the diffraction efficiency matrix of the two-dimensional vector holographic grating waveguide is a 12*12 diffraction efficiency matrix, and then the 12*12 diffraction efficiency matrix is mapped in the diffraction efficiency matrix of each transmission period, and the diffraction efficiency matrix is obtained by the genetic algorithm described above. After obtaining the diffraction efficiency matrix under each transmission period, the final diffraction efficiency matrix of the two-dimensional vector holographic grating waveguide is obtained by taking a weighted average.

[0078] In a specific embodiment, the absorption rate of the two-dimensional vector holographic grating waveguide is 0.02, the thickness of the waveguide is 1 mm, the transmission angle of the light wave in the waveguide is between 43°-63.4°, the optical path length of the reflection is between 1.86-3.99, the total light intensity of the coupling-in is 150e4 nit, and the effective area size of the two-dimensional vector holographic grating waveguide is 23 mm*23 mm.

[0079] In the case of the central field of view, the transmission angle of the light wave in the waveguide is 53.51°, and the corresponding transmission period is 8. The 12*12 diffraction efficiency matrix is first mapped in the 8*8 diffraction efficiency matrix, and the obtained diffraction efficiency matrix is:

[0080] [0.03, 0.04, 0.05, 0.07, 0.09, 0.14, 0.25, 0.78]

[0081] [0.04, 0.05, 0.06, 0.08, 0.10, 0.15, 0.26, 0.79]

[0082] [0.05, 0.06, 0.07, 0.09, 0.11, 0.16, 0.27, 0.79]

[0083] [0.07, 0.08, 0.09, 0.10, 0.12, 0.17, 0.28, 0.79]

[0084] [0.09, 0.10, 0.11, 0.12, 0.14, 0.19, 0.30, 0.80]

[0085] [0.14, 0.15, 0.16, 0.17, 0.19, 0.23, 0.33, 0.81]

[0086] [0.25, 0.26, 0.27, 0.28, 0.30, 0.33, 0.42, 0.83]

[0087] [0.78, 0.79, 0.79, 0.79, 0.80, 0.81, 0.83, 0.95]

[0088] 8*8 local region coupling-out light intensity is:

[0089] [48599.83, 29085.40, 17595.69, 10390.08, 6386.20, 4323.45, 3347.71, 3767.58]

[0090] [29085.4, 32952.91, 28416.07, 21435.70, 15755.98, 12167.63, 10326.72, 11622.99]

[0091] [17595.69, 28416.07, 31052.94, 27987.33, 23511.11, 19996.72, 18068.7, 19977.02]

[0092] [10390.08, 21435.7, 27987.33, 29007.57, 27096.72, 24823.36, 23407.47, 25090.81]

[0093] [6386.20, 15755.98, 23511.11, 27096.72, 27346.40, 26221.77, 25024.28, 25206.39]

[0094] [4323.45, 12167.63, 19996.72, 24823.36 26221.77, 25338.21, 23277.20, 20485.26]

[0095] [3347.71, 10326.72, 18068.70, 23407.47, 25024.28, 23277.20, 19035.06, 12248.26]

[0096] [3767.58, 11622.99, 19977.02, 25090.81, 25206.39, 20485.26, 12248.26, 2057.72]

[0097] According to the formula ξ C = ξ C1 (1-ξ C1 )ξ C2 , the optimal one-dimensional diffraction efficiency matrix ξ C1 is: [0.016, 0.017, 0.029, 0.031, 0.049, 0.053, 0.071, 0.084, 0.143, 0.153, 0.416, 0.962].

[0098] The corresponding CV curve is shown in Figure 1 .

[0099] In the case of left field of view, the transmission angle of light wave in the waveguide is 43°, and the corresponding transmission period is 12. The 12*12 diffraction efficiency matrix is first mapped in the 12*12 diffraction efficiency matrix, and the obtained diffraction efficiency matrix is:

[0100] [0.02, 0.02, 0.02, 0.03, 0.04, 0.05, 0.05, 0.07, 0.10, 0.15, 0.28, 0.99]

[0101] [0.02, 0.03, 0.03, 0.04, 0.04, 0.05, 0.06, 0.07, 0.10, 0.15, 0.29, 0.99]

[0102] [0.02, 0.03, 0.03, 0.04, 0.05, 0.06, 0.06, 0.07, 0.11, 0.15, 0.29, 0.99]

[0103] [0.03, 0.04, 0.04, 0.05, 0.05, 0.06, 0.07, 0.08, 0.11, 0.16, 0.30, 0.99]

[0104] [0.04, 0.04, 0.05, 0.05, 0.06, 0.07, 0.08, 0.09, 0.12, 0.16, 0.30, 0.99]

[0105] [0.05, 0.05, 0.06, 0.06, 0.07, 0.08, 0.08, 0.10, 0.13, 0.17, 0.31, 0.99]

[0106] [0.05, 0.06, 0.06, 0.07, 0.08, 0.08, 0.09, 0.10, 0.13, 0.18, 0.31, 0.99]

[0107] [0.07, 0.07, 0.07, 0.08, 0.09, 0.10, 0.10, 0.11, 0.14, 0.19, 0.32, 0.99]

[0108] [0.10, 0.10, 0.11, 0.11, 0.12, 0.13, 0.13, 0.14, 0.17, 0.22, 0.34, 0.99]

[0109] [0.15, 0.15, 0.15, 0.16, 0.16, 0.17, 0.18, 0.19, 0.22, 0.26, 0.38, 0.99]

[0110] [0.28, 0.29, 0.29, 0.30, 0.30, 0.31, 0.31, 0.32, 0.34, 0.38, 0.48, 0.99]

[0111] [0.99, 0.99, 0.99, 0.99, 0.99, 0.99, 0.99, 0.99, 0.99, 0.99, 0.99, 1.00]

[0112] 12*12 local area coupling-out light intensity is:

[0113] [23904.00, 15108.81, 8621.32, 5102.87, 2967.50, 1728.60, 943.78, 531.84, 355.19, 235.10, 191.39, 230.38]

[0114] [15108.81, 17913.24, 14783.46, 11226.25, 7903.85, 5366.46, 3348.20, 2108.65, 1533.79, 1094.26, 939.08, 1109.87]

[0115] [8621.32, 14783.46, 15902.39, 14721.21, 12166.15, 9436.63, 6622.98, 4611.38, 3632.05, 2777.89, 2503.88, 2916.32]

[0116] [5102.87, 11226.25, 14721.21, 15892.52, 14932.42, 12908.05, 9999.84, 7574.00, 6355.38, 5139.81, 4803.20, 5475.70]

[0117] [2967.50，7903.85，12166.15，14932.42，15650.77，14854.40，12546.20，10231.16，9061.61，7683.04，7383.22，8211.78]

[0118] [1728.60，5366.46，9436.63，12908.05，14854.40，15277.46，13912.75，12096.03，11194.81，9856.54，9643.41，10395.60]

[0119] [943.78，3348.20，6622.98，9999.84，12546.20，13912.75，13592.47，12557.52，12141.08，11090.06，11044.39，11582.87]

[0120] [531.84，2108.65，4611.38，7574.00，10231.16，12096.03，12557.52，12214.49，12198.27，11432.10，11437.77，11518.52]

[0121] [355.19，1533.79，3632.05，6355.38，9061.61，11194.81，12141.08，12198.27，12204.35，11362.31，10917.64，9929.47]

[0122] [235.10，1094.26，2777.89，5139.81，7683.04，9856.54，11090.06，11432.10，11362.31，10365.84，9309.79，7249.60]

[0123] [191.39，939.08，2503.88，4803.20，7383.22，9643.41，11044.39，11437.77，10917.64，9309.79，7081.92，3620.04]

[0124] [230.38，1109.87，2916.32，5475.70，8211.78，10395.60，11582.87，11518.52，9929.47，7249.60，3620.04，-36.22]

[0125] According to the formula ξ L = ξ L1 (1-ξ L1 )ξ L2 , the optimal one-dimensional diffraction efficiency matrix ξ L1 is: [0.008, 0.013, 0.017, 0.023, 0.03, 0.039, 0.047, 0.059, 0.09, 0.139, 0.279, 0.986].

[0126] The corresponding CV curve is shown in Figure 2 .

[0127] In the case of the right field of view, the transmission angle of the light wave in the waveguide is 63.6°, and the corresponding transmission period is 6. The 12*12 diffraction efficiency matrix is first mapped in the 6*6 diffraction efficiency matrix, and the obtained diffraction efficiency matrix is:

[0128] [0.06, 0.06, 0.09, 0.14, 0.24, 0.71]

[0129] [0.06, 0.07, 0.10, 0.14, 0.25, 0.71]

[0130] [0.09, 0.10, 0.13, 0.17, 0.27, 0.72]

[0131] [0.14, 0.14, 0.17, 0.21, 0.31, 0.73]

[0132] [0.24, 0.25, 0.27, 0.31, 0.39, 0.76]

[0133] [0.71, 0.71, 0.72, 0.73, 0.76, 0.91]

[0134] The 6*6 local area coupling-out light intensity is:

[0135] [87194.62, 44888.11, 29441.36, 19251.03, 14336.94, 15388.09]

[0136] [44888.11, 45343.22, 42596.13, 35483.01, 31063.39, 34577.00]

[0137] [29441.36, 42596.13, 47704.13, 44691.54, 41379.30, 43636.74]

[0138] [19251.03, 35483.01, 44691.54, 44895.43, 41849.32, 39504.45]

[0139] [14336.94, 31063.39, 41379.30, 41849.32, 36001.77, 25866.69]

[0140] [15388.09, 34577.00, 43636.74, 39504.45, 25866.69, 6661.09]

[0141] According to the formula ξ R = ξ R1 +(1-ξ R1 )ξ R2 , the optimal one-dimensional diffraction efficiency matrix ξ R1 is obtained: [0.029, 0.03, 0.036, 0.037, 0.062, 0.069, 0.109, 0.113, 0.215, 0.224, 0.664, 0.73].

[0142] The corresponding CV curve is shown in Figure 3 .

[0143] For other field of view cases, the corresponding optimal one-dimensional diffraction efficiency matrix can also be calculated. Finally, the optimal solution of the diffraction efficiency matrix of the two one-dimensional gratings forming the two-dimensional vector holographic grating waveguide can be obtained by weighting and averaging the optimal one-dimensional diffraction efficiency matrix obtained under each field of view.

[0144] Finally, according to the linear relationship between the diffraction efficiency of the one-dimensional grating and the exposure energy used in the grating manufacturing, the exposure energy required for manufacturing the two-dimensional vector holographic grating waveguide is obtained.

[0145] Step S2, using the exposure energy to expose the two-dimensional vector holographic grating waveguide.

[0146] Specifically, by adjusting the energy of the exposure light beam emitted by the exposure light source, and / or adjusting the exposure time of the holographic plate, so that the exposure energy of the exposure light beam irradiated to the holographic plate is the exposure energy obtained according to the embodiment of the present application, and then the holographic plate is exposed.

[0147] The implementation principle of the manufacturing method of the two-dimensional vector holographic grating waveguide provided in the embodiment is: under the premise of balancing the output luminance of the entire exit pupil, the exposure energy for manufacturing the two-dimensional vector holographic grating waveguide is calculated by using the formula group provided in the application, so that the exposure energy is used for exposure processing on a holographic plate, and an optimized two-dimensional vector holographic grating waveguide is obtained. The method optimizes the exit pupil uniformity of the two-dimensional vector holographic grating waveguide, and improves the final eye-into display effect of the near-eye device.

[0148] Embodiment 2

[0149] The embodiment provides a two-dimensional vector holographic grating waveguide, which is prepared by using the manufacturing method in the embodiment 1.

[0150] Embodiment 3

[0151] The embodiment provides an optical waveguide module, which comprises an optical machine and the two-dimensional vector holographic grating waveguide in the embodiment 2.

[0152] The above are preferred embodiments of the application, and are not intended to limit the protection scope of the application, so that: any equivalent changes made according to the structure, shape, principle of the application should be covered within the protection scope of the application.

Claims

1. A method for fabricating a two-dimensional vector volume holographic grating waveguide, characterized in that, include: S1. The two-dimensional diffraction efficiency matrix of the two-dimensional vector volume holographic grating waveguide at different propagation angles is obtained according to the following set of formulas, thereby obtaining the diffraction efficiency matrices of the two one-dimensional gratings forming the two-dimensional vector volume holographic grating waveguide. Based on the linear relationship between the diffraction efficiency of the one-dimensional grating and the exposure energy used in grating fabrication, the exposure energy required for fabricating the two-dimensional vector volume holographic grating waveguide is obtained. The set of formulas is as follows: Among them, Angle t The angle of propagation of the light wave within the two-dimensional vector volume holographic grating waveguide is represented by m and n, where m and n represent the angles of propagation. t The propagation period of the light wave in the two-dimensional vector volume holographic grating waveguide at (1, 2, ..., T) In terms of communication, Angle t The propagation intensity of the light wave in the two-dimensional vector volume holographic grating waveguide at (1, 2, ..., T) In terms of communication, Angle t The coupled light intensity of the light wave in each local region of the two-dimensional vector volume holographic grating waveguide under (1, 2, ..., T) In terms of communication, Angle t The average value of the coupled light intensity of the light wave in each local region of the two-dimensional vector volume holographic grating waveguide under (1, 2, ..., T). In terms of communication, Angle t The two-dimensional diffraction efficiency matrix of the two-dimensional vector volume holographic grating waveguide described in (1, 2, ..., T); α is the absorptivity of the volume holographic grating; S2. The holographic plate is exposed using the exposure energy to obtain the two-dimensional vector volume holographic grating waveguide.

2. The method for fabricating a two-dimensional vector volume holographic grating waveguide according to claim 1, characterized in that, The step of obtaining the diffraction efficiency matrix of the two one-dimensional gratings forming the two-dimensional vector volume holographic grating waveguide includes: The two-dimensional diffraction efficiency matrix under all propagation angles is weighted and averaged to obtain the two-dimensional diffraction efficiency matrix under the full field of view; Based on the two-dimensional diffraction efficiency matrix under the full field of view, the diffraction efficiency matrices of the two one-dimensional gratings forming the two-dimensional vector volume holographic grating waveguide are obtained.

3. The method for fabricating a two-dimensional vector volume holographic grating waveguide according to claim 2, characterized in that, The step of obtaining the diffraction efficiency matrices of the two one-dimensional gratings forming the two-dimensional vector volume holographic grating waveguide based on the two-dimensional diffraction efficiency matrix under the full field of view includes: According to the formula ξ=ξ1+(1-ξ1)ξ2, the diffraction efficiency matrices ξ1 and ξ2 of the two one-dimensional gratings forming the two-dimensional vector volume holographic grating waveguide are obtained; where ξ represents the two-dimensional diffraction efficiency matrix under the full field of view, ξ1 and ξ2 respectively represent the diffraction efficiency matrices of the two one-dimensional gratings forming the two-dimensional vector volume holographic grating waveguide, and ξ1 and ξ2 are transposes of each other.

4. The method for fabricating a two-dimensional vector volume holographic grating waveguide according to claim 1, characterized in that, The step of obtaining the diffraction efficiency matrix of the two one-dimensional gratings forming the two-dimensional vector volume holographic grating waveguide includes: According to the formula The above The diffraction efficiency matrices ξ of the two corresponding one-dimensional gratings t1 and ξ t2 ; where ξ t1 and ξ t2 Each represents the formation of the above The diffraction efficiency matrices of the two one-dimensional gratings, ξ t1 and ξ t2 They are transposes of each other; For all propagation angles, the ξ t1 Perform a weighted average for ξ at all propagation angles. t2 By performing weighted averaging, the diffraction efficiency matrices ξ1 and ξ2 of the two one-dimensional gratings forming the two-dimensional vector volume holographic grating waveguide are obtained.

5. The method for fabricating a two-dimensional vector volume holographic grating waveguide according to claim 3, characterized in that, The step of exposing the holographic plate with the exposure energy to obtain the two-dimensional vector volume holographic grating waveguide includes: Adjust the energy of the exposure beam emitted from the exposure light source so that the exposure energy of the exposure beam illuminating the holographic plate is the exposure energy obtained according to ξ1 or ξ2.

6. The method for fabricating a two-dimensional vector volume holographic grating waveguide according to claim 5, characterized in that, The step of adjusting the energy of the exposure beam emitted from the exposure light source so that the exposure energy of the exposure beam illuminating the holographic plate is the exposure energy obtained according to ξ1 or ξ2 includes: Adjust the energy of the exposure beam emitted from the exposure light source, and / or adjust the exposure time of the holographic plate.

7. A two-dimensional vector volume holographic grating waveguide, characterized in that, It is fabricated using the fabrication method of any one of claims 1 to 6 for a two-dimensional vector volume holographic grating waveguide.

8. An optical waveguide module, characterized in that, It includes an optomechanic and the two-dimensional vector volume holographic grating waveguide as described in claim 7.

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