A high beam splitter for one-dimensional and two-dimensional binary Damman gratings

Abstract

This invention discloses a binary pure-phase Damman grating beamsplitter, specifically comprising one-dimensional Damman gratings with beam splitting numbers of 33–63, 65, 67, and 128. A two-dimensional Damman grating can be constructed by cross-stacking two one-dimensional binary pure-phase Damman gratings along a certain included angle, with adjacent regions having a phase difference of π. This invention discloses the 0-π phase transition points and tolerance ranges, corresponding diffraction efficiencies, intensity uniformity, and minimum linewidth within the normalized period of the Damman gratings for beam splitting numbers of 33–63, 65, 67, and 128, within the scalar theoretical range. The scalar Damman grating numerical solution provided by this invention allows for the convenient design of one-dimensional and two-dimensional Damman grating beamsplitters with various periods, achieving a maximum beam splitting scale of 16384 (128×128) paths. This large-scale Damman grating beamsplitter has wide application value in large-scale optical interconnects, beam shaping, array structured light illumination, and optical computing.

Description

Technical Field

[0001] This invention relates to a novel diffractive optical beam splitter, particularly a large beam splitting ratio binary 0-π phase Damman grating beam splitter. Background Technology

[0002] Damman gratings are optical elements capable of large-scale, equal-intensity beam splitting and diffraction, and have been widely used in optical computing, optical switching, multi-line structured light, optical communication, and parallel laser direct writing. The basic design principle of Damman gratings is to incorporate 0-π modulation details within a single period of a conventional grating, thereby achieving energy redistribution between its diffraction spectral points. This phase modulation detail is achieved by adjusting the spatial position of the phase transition from 0 to π or from π to 0, i.e., the phase inflection point, to control the beam splitting ratio and energy. As early as 1995, Zhou Changhe et al. systematically presented numerical solutions for Damman gratings from 1×2 to 1×32 and 1×64 array numbers [Prior Art: C, Zhou, and L. Liu, Appl. Opt. 34, 5961-5969 (1995)]. With the widespread application of Damman gratings, larger-scale Damman grating beam splitters are receiving increasing attention. However, in the more than 20 years since Zhou et al. systematically presented numerical solutions for Damman gratings with array sizes of 1×2 to 1×32 and 1×64, no numerical solutions for larger-scale Damman gratings have been reported. The main reason for this is that the solution space of Damman gratings increases rapidly with the increase of beam splitting scale, the number of phase inflection points required increases, the solution space becomes increasingly large, and the computational power and time required also increase dramatically. Summary of the Invention

[0003] This invention proposes large-scale one-dimensional and two-dimensional Damman beam-splitter gratings ranging from 1×33 to 1×63, as well as 1×65, 1×67, and 1×128. Conventional fused silica glass is used as the grating substrate, and a two-step relief grating structure is achieved through standard photolithography and etching processes. The grating ridges and grooves are made of two alternating materials, with corresponding step depths satisfying… Where n1 and n2 are the refractive indices of the grating ridge and grating groove, respectively, for the working center wavelengths of the two materials. Furthermore, this Dammann grating can also introduce 0 and π phases through the geometric phase mechanism of metasurface units or liquid crystals. Through the aforementioned 0 and π phase modulation, the corresponding design distribution of diffraction spectral points at the working wavelength can be achieved, i.e., the corresponding order of equal-energy beam splitting effect.

[0004] The specific technical solution of the present invention is as follows:

[0005] A high beam-splitting ratio binary pure-phase one-dimensional Damman grating beam splitter, characterized in that: the high beam-splitting ratio binary pure-phase Damman grating beam splitter is a pure-phase element; each grating period has N alternating abrupt change regions of phase delay 0 and π, where N is a positive integer greater than 10; the boundary coordinates of the alternating 0 and π change regions divided by the grating period are defined as normalized inflection points, which can be written as {x n}, where n = 0, 1, 2, ..., N+1, and the normalized phase inflection point satisfies x0 <x1<x2...<x N+1 And x0=0,x N+1 =1; The normalized minimum linewidth of the large beam-splitting ratio binary pure-phase Damman grating satisfies Δx>λ / Λ, where λ is the operating wavelength corresponding to the Damman grating, and Λ is the corresponding grating period; Δx=min{x n+1 -x n} represents the normalized minimum linewidth of the Damman grating, where n = 0, 1, 2, ... N.

[0006] The large beam splitting ratio binary pure phase one-dimensional Damman grating beam splitter is characterized in that the total number of phase inflection points in each period of the Damman grating with an odd number of beam splits is also odd.

[0007] The aforementioned high-splitting-ratio binary pure-phase one-dimensional Damman grating beam splitter is characterized by the fact that the total number of phase inflection points in the first half of the Damman grating period is even, and the phase distribution in the first half of the grating period is reversed relative to the phase distribution in the second half of the grating period. Specifically, the normalized phase inflection point in the second half of the period is obtained by adding 0.5 to the normalized phase inflection point in the first half of the period. Thus, all normalized phase inflection points in one period can be represented as {x}. n ,0.5,x n +0.5}, where {x n} represents the set of normalized phase inflection points for the first half of the cycle.

[0008] Preferably, the high beam-splitting ratio binary pure-phase Damman grating beam splitter is characterized in that the substrate material of the Damman grating has a transmittance greater than 90% in the operating wavelength band; the grating ridge and grating groove are made of two alternating materials in two steps, with the corresponding step depths satisfying... Where n1 and n2 are the refractive indices of the working center wavelengths of the ridge and groove of the two materials, respectively.

[0009] Preferably, the large beam splitting ratio binary pure phase Damman grating beam splitter is characterized in that the substrate material of the Damman grating has a transmittance of greater than 90% in the working band, and the 0 and π binary phases of the grating are introduced through a metasurface unit structure.

[0010] Preferably, the large beam splitting ratio binary pure phase Damman grating beam splitter is characterized in that the substrate material of the Damman grating has a transmittance of greater than 90% in the working band, and the 0 and π binary phases of the grating are introduced through the refractive index difference of the liquid crystal material.

[0011] Preferably, the large beam-splitting ratio binary pure-phase one-dimensional Damman grating beam splitter is characterized in that the normalized phase inflection points within a single period corresponding to the 1×33 Damman grating beam splitter are 0.03746±0.0041, 0.06314±0.004, 0.09628±0.0039, 0.14396±0.004, 0.16501±0.0039, 0.25524±0.004, and 0.299, respectively. 77±0.004, 0.37625±0.004, 0.42607±0.0039, 0.55078±0.0044, 0.66772±0.0039, 0.69421±0.004, 0.74751±0.0039, 0.78299±0.0041, 0.82667±0.0039, 0.87814±0.004, 0.89979±0.0039.

[0012] Preferably, the large beam-splitting ratio binary pure-phase one-dimensional Damman grating beam splitter is characterized in that the normalized phase inflection points in the first half-cycle corresponding to the 1×34 Damman grating beam splitter are 0.03417±0.002, 0.09451±0.0019, 0.11439±0.002, 0.16201±0.002, 0.1719±0.002, 0.19444±0.002, and 0.21301±0.002, respectively. 0.22361±0.0019,0.24276±0.0019,0.25366±0.0022,0.30238±0.0019,0.32675±0.0019,0.3548±0.002,0.37162±0.0022,0.39092±0.0019,0.40727±0.002,0.46128±0.0019,0.48783±0.0019.

[0013] Preferably, the large beam-splitting ratio binary pure-phase one-dimensional Damman grating beam splitter is characterized in that the normalized phase inflection points within a single period corresponding to the 1×35 Damman grating beam splitter are 0.01784±0.0038, 0.05401±0.0039, 0.09641±0.0038, 0.1775±0.0038, 0.20321±0.0038, 0.25266±0.0039, 0.3214±0.0038, and 0.353, respectively. 49±0.0039, 0.3914±0.0038, 0.43614±0.0038, 0.45091±0.0038, 0.5092±0.0038, 0.5368±0.0038, 0.56022±0.0039, 0.61195±0.0038, 0.6379±0.0038, 0.73011±0.0038, 0.81701±0.0038, 0.86288±0.0038.

[0014] Preferably, the large beam-splitting ratio binary pure-phase one-dimensional Damman grating beam splitter is characterized in that the normalized phase inflection points within the first half-cycle corresponding to the 1×36 Damman grating beam splitter are 0.00865±0.002, 0.02722±0.0019, 0.03931±0.0022, 0.05582±0.0019, 0.07379±0.0019, 0.12769±0.0019, and 0.14151±0.0019, respectively. 019, 0.19101±0.002, 0.21552±0.0019, 0.23528±0.002, 0.25949±0.0019, 0.27766±0.0019, 0.29489±0.002, 0.31323±0.002, 0.34737±0.002, 0.42404±0.0019, 0.46445±0.0019, 0.48124±0.0019.

[0015] Preferably, the large beam-splitting ratio binary pure-phase one-dimensional Damman grating beam splitter is characterized in that the normalized phase inflection points within a single period corresponding to the 1×37 Damman grating beam splitter are 0.04016±0.0037, 0.06173±0.0037, 0.08602±0.0037, 0.12329±0.0037, 0.22432±0.0037, 0.24267±0.0037, 0.37728±0.0038, and 0.4712, respectively. 1±0.0038, 0.49537±0.0037, 0.53283±0.0038, 0.60207±0.0037, 0.68156±0.0037, 0.72064±0.0038, 0.74909±0.0038, 0.78161±0.0037, 0.81556±0.0037, 0.88177±0.0037, 0.91847±0.0037, 0.96111±0.0039.

[0016] Preferably, the large beam-splitting ratio binary pure-phase one-dimensional Damman grating beam splitter is characterized in that the normalized phase inflection points within the first half-cycle corresponding to the 1×38 Damman grating beam splitter are 0.01777±0.0019, 0.03208±0.0018, 0.07474±0.0019, 0.08652±0.0019, 0.1048±0.0018, 0.11627±0.0018, 0.14619±0.0018, and 0.16854±0.001, respectively. 8, 0.20175±0.0019, 0.22956±0.0018, 0.24944±0.0019, 0.26906±0.0018, 0.27856±0.0019, 0.29614±0.0018, 0.30917±0.0019, 0.32948±0.0018, 0.3397±0.0019, 0.40522±0.002, 0.46115±0.0018, 0.48922±0.0019.

[0017] Preferably, the large beam-splitting ratio binary pure-phase one-dimensional Damman grating beam splitter is characterized in that the normalized phase inflection points within a single period corresponding to the 1×39 Damman grating beam splitter are 0.02682±0.0036, 0.057±0.0036, 0.10664±0.0036, 0.16312±0.0036, 0.21146±0.0036, 0.24267±0.0036, 0.2712±0.0036, 0.29581±0.0036, and 0.324. 56±0.0036,0.4039±0.0036,0.44899±0.0036,0.4699±0.0036,0.499±0.0036,0.51157±0.0036,0.54344±0.0036,0.72421±0.0036,0.75491±0.0036,0.78948±0.0036,0.81117±0.0036,0.86579±0.0037,0.95429±0.0036.

[0018] Preferably, the large beam-splitting ratio binary pure-phase one-dimensional Damman grating beam splitter is characterized in that the normalized phase inflection points within the first half-cycle corresponding to the 1×40 Damman grating beam splitter are 0.01633±0.0018, 0.04399±0.0019, 0.06307±0.0018, 0.15185±0.0018, 0.17115±0.0019, 0.18231±0.0018, 0.21982±0.0019, and 0.25178±0.001. 8, 0.29613±0.0018, 0.31111±0.0018, 0.32837±0.0018, 0.34921±0.0018, 0.36364±0.0018, 0.37688±0.0019, 0.39274±0.0018, 0.40334±0.0018, 0.41743±0.0018, 0.43167±0.0019, 0.4669±0.0018, 0.48846±0.0019.

[0019] Preferably, the large beam-splitting ratio binary pure-phase one-dimensional Damman grating beam splitter is characterized in that the normalized phase inflection points within a single period corresponding to the 1×41 Damman grating beam splitter are 0.0603±0.0036, 0.10366±0.0036, 0.17873±0.0036, 0.20972±0.0036, 0.25728±0.0036, 0.28773±0.0036, 0.31798±0.0036, 0.34881±0.0037, and 0.3804. 8±0.0036, 0.41375±0.0036, 0.43251±0.0036, 0.44594±0.0035, 0.47801±0.0036, 0.51213±0.0036, 0.53908±0.0036, 0.65661±0.0036, 0.79506±0.0036, 0.83194±0.0035, 0.92013±0.0036, 0.94966±0.0035, 0.97102±0.0036.

[0020] Preferably, the large beam-splitting ratio binary pure-phase one-dimensional Damman grating beam splitter is characterized in that the normalized phase inflection points in the first half-cycle corresponding to the 1×42 Damman grating beam splitter are 0.04238±0.0018, 0.11207±0.0018, 0.11741±0.0018, 0.14118±0.0018, 0.15767±0.0018, 0.1755±0.0018, 0.1951±0.0018, 0.21351±0.0018, and 0.22589±0.0018. ,0.23632±0.0018,0.25487±0.0018,0.26141±0.0018,0.27763±0.0018,0.29214±0.0018,0.32471±0.0018,0.34174±0.0018,0.35378±0.0018,0.36695±0.0018,0.40868±0.0018,0.43455±0.0018,0.46831±0.0018,0.48377±0.0018.

[0021] Preferably, the large beam-splitting ratio binary pure-phase one-dimensional Damman grating beam splitter is characterized in that the normalized phase inflection points within a single period corresponding to the 1×43 Damman grating beam splitter are 0.03213±0.0034, 0.07242±0.0034, 0.09176±0.0035, 0.13285±0.0034, 0.18249±0.0035, 0.19474±0.0034, 0.22954±0.0034, 0.25696±0.0035, 0.2826±0.0034, and 0.31. 24±0.0034,0.3371±0.0034,0.3641±0.0035,0.38376±0.0035,0.41763±0.0034,0.43024±0.0034,0.45568±0.0035,0.50905±0.0035,0.54023±0.0035,0.58352±0.0035,0.63013±0.0035,0.67042±0.0034,0.74348±0.0034,0.8197±0.0034.

[0022] Preferably, the large beam-splitting ratio binary pure-phase one-dimensional Damman grating beam splitter is characterized in that the normalized phase inflection points in the first half-cycle corresponding to the 1×44 Damman grating beam splitter are 0.07589±0.0017, 0.08702±0.0017, 0.10605±0.0017, 0.12232±0.0017, 0.14316±0.0017, 0.17938±0.0017, 0.20112±0.0017, 0.2206±0.0017, 0.26384±0.0017, and 0.27373±0.00. 19, 0.27892±0.0017, 0.29849±0.0017, 0.31212±0.0017, 0.32305±0.0017, 0.33733±0.0017, 0.34839±0.0017, 0.36318±0.0017, 0.37651±0.0017, 0.40782±0.0018, 0.42604±0.0017, 0.4334±0.0017, 0.46±0.0018, 0.47963±0.0017, 0.48789±0.0017.

[0023] Preferably, the large beam-splitting ratio binary pure-phase one-dimensional Damman grating beam splitter is characterized in that the normalized phase inflection points within a single period corresponding to the 1×45 Damman grating beam splitter are 0.0278±0.0033, 0.07401±0.0033, 0.09532±0.0033, 0.15294±0.0033, 0.17034±0.0033, 0.19929±0.0033, 0.23554±0.0033, 0.30226±0.0035, 0.42237±0.0033, 0.48182±0.0033, and 0.509. 48±0.0033,0.53421±0.0033,0.55948±0.0034,0.5831±0.0034,0.62261±0.0033,0.6323±0.0034,0.67915±0.0033,0.70412±0.0033,0.74771±0.0033,0.76294±0.0033,0.77853±0.0033,0.80452±0.0033,0.87826±0.0033,0.90494±0.0033,0.97563±0.0033.

[0024] Preferably, the large beam-splitting ratio binary pure-phase one-dimensional Damman grating beam splitter is characterized in that the normalized phase inflection points in the first half-cycle corresponding to the 1×46 Damman grating beam splitter are 0.0341±0.0017, 0.05074±0.0017, 0.0634±0.0017, 0.08217±0.0017, 0.09021±0.0017, 0.11317±0.0017, 0.15209±0.0017, 0.16455±0.0017, 0.17821±0.0017, and 0.1889±0.001. 7, 0.20249±0.0017, 0.21426±0.0017, 0.22316±0.0017, 0.25489±0.0017, 0.29581±0.0017, 0.31154±0.0017, 0.33542±0.0017, 0.34461±0.0017, 0.40145±0.0017, 0.4139±0.0017, 0.4245±0.0017, 0.43842±0.0018, 0.4653±0.0017, 0.48877±0.0018.

[0025] Preferably, the large beam-splitting ratio binary pure-phase one-dimensional Damman grating beam splitter is characterized in that the normalized phase inflection points within a single period corresponding to the 1×47 Damman grating beam splitter are 0.03143±0.0033, 0.04881±0.0033, 0.11615±0.0033, 0.12793±0.0033, 0.16221±0.0033, 0.18225±0.0033, 0.21706±0.0033, 0.24967±0.0034, 0.27165±0.0033, 0.30627±0.0033, and 0.3268. 8±0.0033, 0.39725±0.0033, 0.45685±0.0033, 0.55025±0.0033, 0.57259±0.0033, 0.63549±0.0033, 0.67592±0.0033, 0.70412±0.0033, 0.74771±0.0033, 0.82164±0.0033, 0.83367±0.0033, 0.86435±0.0033, 0.88681±0.0034, 0.91242±0.0033, 0.93608±0.0034.

[0026] Preferably, the large beam-splitting ratio binary pure-phase one-dimensional Damman grating beam splitter is characterized in that the normalized phase inflection points in the first half-cycle corresponding to the 1×48 Damman grating beam splitter are 0.01764±0.0018, 0.04726±0.0017, 0.05392±0.0016, 0.06795±0.0016, 0.07992±0.0017, 0.1058±0.0016, 0.13484±0.0016, 0.15133±0.0016, 0.17516±0.0016, 0.18854±0.0016, and 0.20632±0.001. 6, 0.21501±0.0017, 0.22871±0.0016, 0.24216±0.0016, 0.25191±0.0017, 0.26153±0.0016, 0.2741±0.0017, 0.28841±0.0017, 0.29698±0.0016, 0.31961±0.0017, 0.33523±0.0016, 0.34907±0.0016, 0.35712±0.0016, 0.40023±0.0016, 0.42874±0.0016, 0.49218±0.0017.

[0027] Preferably, the large beam-splitting ratio binary pure-phase one-dimensional Damman grating beam splitter is characterized in that the normalized phase inflection points within a single period corresponding to the 1×49 Damman grating beam splitter are 0.02577±0.0032, 0.0562±0.0031, 0.13073±0.0032, 0.1848±0.0032, 0.19812±0.0032, 0.22684±0.0032, 0.2828±0.0032, 0.30572±0.0032, 0.3377±0.0032, 0.36034±0.0032, 0.38761±0.0032, 0.40562. ±0.0032, 0.4333±0.0032, 0.44855±0.0032, 0.4684±0.0032, 0.56061±0.0032, 0.58145±0.0032, 0.65504±0.0031, 0.67505±0.0032, 0.72478±0.0031, 0.76108±0.0032, 0.78718±0.0032, 0.80405±0.0032, 0.82812±0.0032, 0.88167±0.0032, 0.94622±0.0032, 0.95951±0.0032.

[0028] Preferably, the large beam-splitting ratio binary pure-phase one-dimensional Damman grating beam splitter is characterized in that the normalized phase inflection points in the first half-cycle corresponding to the 1×50 Damman grating beam splitter are 0.0123±0.0016, 0.03103±0.0016, 0.05887±0.0016, 0.06863±0.0016, 0.08271±0.0016, 0.08921±0.0016, 0.09706±0.0016, 0.11025±0.0016, 0.12228±0.0016, 0.13541±0.0016, 0.14967±0.0016, and 0.17261±0.00. 16, 0.18078±0.0016, 0.19821±0.0016, 0.21408±0.0016, 0.24799±0.0016, 0.2645±0.0016, 0.27629±0.0016, 0.28382±0.0016, 0.321±0.0016, 0.33411±0.0016, 0.37321±0.0017, 0.38744±0.0016, 0.39604±0.0016, 0.44371±0.0016, 0.47268±0.0016, 0.47998±0.0016, 0.49416±0.0016.

[0029] Preferably, the large beam-splitting ratio binary pure-phase one-dimensional Damman grating beam splitter is characterized in that the normalized phase inflection points within a single period corresponding to the 1×51 Damman grating beam splitter are 0.03409±0.0032, 0.11826±0.0032, 0.1526±0.0033, 0.18045±0.0032, 0.19719±0.0032, 0.22504±0.0032, 0.2456±0.0031, 0.25958±0.0032, 0.28576±0.0032, 0.31034±0.0032, 0.33396±0.0032, and 0.37632, respectively. ±0.0032, 0.40159±0.0032, 0.46093±0.0032, 0.48918±0.0032, 0.51209±0.0032, 0.53348±0.0032, 0.59998±0.0032, 0.61423±0.0032, 0.67338±0.0032, 0.72227±0.0032, 0.78298±0.0032, 0.79754±0.0032, 0.83655±0.0032, 0.92991±0.0032, 0.94903±0.0032, 0.98478±0.0031.

[0030] Preferably, the large beam-splitting ratio binary pure-phase one-dimensional Damman grating beam splitter is characterized in that the normalized phase inflection points in the first half-cycle corresponding to the 1×52 Damman grating beam splitter are 0.00915±0.0016, 0.02524±0.0016, 0.03437±0.0016, 0.05272±0.0016, 0.06629±0.0016, 0.11232±0.0016, 0.12262±0.0016, 0.13609±0.0016, 0.14444±0.0016, 0.1558±0.0016, 0.16654±0.0016, and 0.17846±0.0016. ,0.19024±0.0016,0.21521±0.0015,0.23115±0.0016,0.23736±0.0016,0.26537±0.0016,0.27746±0.0016,0.28833±0.0016,0.32824±0.0015,0.33942±0.0016,0.37954±0.0016,0.40611±0.0016,0.41538±0.0016,0.43234±0.0016,0.46227±0.0016,0.48427±0.0016,0.49377±0.0016.

[0031] Preferably, the large beam-splitting ratio binary pure-phase one-dimensional Damman grating beam splitter is characterized in that the normalized phase inflection points within a single period corresponding to the 1×53 Damman grating beam splitter are 0.03368±0.0031, 0.07234±0.0031, 0.09549±0.0031, 0.12323±0.0031, 0.15079±0.0031, 0.17732±0.0031, 0.19698±0.0031, 0.21764±0.0031, 0.24288±0.0031, 0.25635±0.0031, 0.28071±0.0031, 0.30321±0.0031, 0.367 79±0.0032, 0.38478±0.0031, 0.39936±0.0031, 0.41449±0.0031, 0.44228±0.0031, 0.46676±0.0031, 0.5433±0.0031, 0.56996±0.0031, 0.60419±0. 0031, 0.65867±0.0031, 0.67446±0.0031, 0.69185±0.0031, 0.78585±0.0031, 0.79469±0.0031, 0.82192±0.0031, 0.85748±0.0031, 0.91005±0.0031.

[0032] Preferably, the large beam-splitting ratio binary pure-phase one-dimensional Damman grating beam splitter is characterized in that the normalized phase inflection points in the first half-cycle corresponding to the 1×54 Damman grating beam splitter are 0.03119±0.0015, 0.06352±0.0015, 0.10765±0.0015, 0.11301±0.0015, 0.12471±0.0015, 0.13717±0.0015, 0.15267±0.0015, 0.16434±0.0015, 0.18488±0.0015, 0.19914±0.0015, 0.2356±0.0015, 0.2508±0.0015, and 0.27122±0.0015. ,0.28978±0.0015,0.2951±0.0015,0.31184±0.0015,0.31769±0.0015,0.32851±0.0015,0.33983±0.0016,0.35007±0.0015,0.36681±0.0015,0.37606 ±0.0016, 0.40766±0.0015, 0.41872±0.0015, 0.44354±0.0015, 0.45125±0.0015, 0.46315±0.0015, 0.47364±0.0015, 0.48245±0.0015, 0.49314±0.0015.

[0033] Preferably, the large beam-splitting ratio binary pure-phase one-dimensional Damman grating beam splitter is characterized in that the normalized phase inflection points within a single period corresponding to the 1×55 Damman grating beam splitter are 0.01411±0.003, 0.03817±0.003, 0.06309±0.0031, 0.08238±0.003, 0.09492±0.003, 0.1215±0.003, 0.1742±0.003, 0.18615±0.003, 0.24689±0.0031, 0.26844±0.0031, 0.28999±0.003, 0.31558±0.003, and 0.3501, respectively. 5±0.003, 0.39596±0.003, 0.42063±0.0031, 0.45663±0.003, 0.47393±0.0031, 0.48824±0.003, 0.53086±0.0031, 0.6061±0.003, 0.63002±0.0033, 0.66144±0.0031, 0.68666±0.003, 0.70632±0.003, 0.77363±0.003, 0.81727±0.003, 0.93478±0.003, 0.95883±0.0031, 0.97961±0.0031.

[0034] Preferably, the large beam-splitting ratio binary pure-phase one-dimensional Damman grating beam splitter is characterized in that the normalized phase inflection points in the first half-cycle corresponding to the 1×56 Damman grating beam splitter are 0.03037±0.0015, 0.04334±0.0015, 0.05786±0.0015, 0.07233±0.0015, 0.08268±0.0015, 0.11851±0.0015, 0.13525±0.0015, 0.14171±0.0015, 0.17017±0.0015, 0.17511±0.0015, 0.20734±0.0015, 0.21798±0.0015, and 0.22902±0.001. 5, 0.23774±0.0015, 0.26128±0.0015, 0.27297±0.0015, 0.29838±0.0015, 0.33079±0.0015, 0.35634±0.0016, 0.36644±0.0015, 0.37839±0.0015, 0.4073 9±0.0015, 0.41308±0.0015, 0.42112±0.0015, 0.43627±0.0015, 0.44791±0.0015, 0.45749±0.0016, 0.47275±0.0015, 0.48026±0.0015, 0.48979±0.0015.

[0035] Preferably, the large beam-splitting ratio binary pure phase one-dimensional Damman grating beam splitter is characterized in that the normalized phase inflection points within a single period corresponding to the 1×57 Damman grating beam splitter are 0.05358±0.0029, 0.0645±0.003, 0.08278±0.0029, 0.10281±0.003, 0.12334±0.003, 0.15895±0.003, 0.19198±0.003, 0.2169±0.003, 0.23974±0.003, 0.28842±0.003, 0.32374±0.003, 0.34966±0.003, 0.36981±0.003, 0. 38744±0.003, 0.40677±0.003, 0.42388±0.0029, 0.44956±0.003, 0.46989±0.003, 0.48469±0.003, 0.52459±0.003, 0.53525±0.003, 0.5718±0.003, 0.59152±0.003, 0.678±0.003, 0.70008±0.003, 0.76554±0.003, 0.81202±0.003, 0.83301±0.003, 0.89889±0.003, 0.91724±0.003, 0.93016±0.003.

[0036] Preferably, the large beam-splitting ratio binary pure-phase one-dimensional Damman grating beam splitter is characterized in that the normalized phase inflection points within the first half-cycle corresponding to the 1×58 Damman grating beam splitter are 0.06957±0.0015, 0.11211±0.0015, 0.12826±0.0015, 0.13323±0.0015, and 0.14257±0.0015, respectively. 0.15, 0.16134±0.0015, 0.17341±0.0015, 0.17941±0.0015, 0.19376±0.0015, 0.20943±0.0015, 0.22152±0.0015, 0.2278±0.0015, 0.24292±0.0015, 0.24901±0.00 15, 0.25399±0.0015, 0.2682±0.0015, 0.27693±0.0015, 0.28915±0.0015, 0.2973±0.0015, 0.30779±0.0015, 0.31783±0.0015, 0.32417±0.0015, 0.33541±0.0015 ,0.34811±0.0016,0.36756±0.0015,0.3766±0.0016,0.38745±0.0015,0.41051±0.0015,0.42515±0.0016,0.44435±0.0015,0.45732±0.0015,0.48641±0.0015.

[0037] Preferably, the large beam-splitting ratio binary pure-phase one-dimensional Damman grating beam splitter is characterized in that the normalized phase inflection points within a single period corresponding to the 1×59 Damman grating beam splitter are 0.01838±0.0029, 0.03824±0.0029, 0.05983±0.0029, 0.08159±0.0029, 0.09423±0.0029, 0 0.11482±0.0029, 0.12857±0.0029, 0.13899±0.0029, 0.17073±0.0029, 0.19491±0.0029, 0.23307±0.0029, 0.25466±0.0029, 0.30714±0.0029, 0.32191±0.0029, 0.3325 6±0.0029, 0.37908±0.0029, 0.41131±0.0029, 0.47268±0.0029, 0.48564±0.0029, 0.54678±0.0029, 0.55792±0.0029, 0.59037±0.0029, 0.60812±0.0029, 0.62428±0. 0029, 0.65035±0.0029, 0.68508±0.0029, 0.71502±0.0029, 0.73572±0.0029, 0.75517±0.0029, 0.82427±0.0029, 0.84642±0.0029, 0.86645±0.0029, 0.93805±0.0029.

[0038] Preferably, the large beam-splitting ratio binary pure-phase one-dimensional Damman grating beam splitter is characterized in that the normalized phase inflection points within the first half-cycle corresponding to the 1×60 Damman grating beam splitter are 0.02422±0.0015, 0.04156±0.0015, 0.05603±0.0015, 0.08577±0.0015, and 0.09113±0.00, respectively. 15, 0.09968±0.0015, 0.11925±0.0015, 0.12893±0.0015, 0.14095±0.0015, 0.15321±0.0015, 0.17625±0.0015, 0.18646±0.0015, 0.19669±0.0015, 0.20451±0.00 15, 0.21367±0.0015, 0.22646±0.0015, 0.23286±0.0015, 0.24531±0.0015, 0.25719±0.0015, 0.2635±0.0015, 0.30856±0.0015, 0.31481±0.0015, 0.3259±0.0015 ,0.34218±0.0015,0.37597±0.0015,0.38804±0.0015,0.41135±0.0015,0.42044±0.0015,0.43266±0.0015,0.47128±0.0014,0.47903±0.0015,0.48558±0.0015.

[0039] Preferably, the large beam-splitting ratio binary pure-phase one-dimensional Damman grating beam splitter is characterized in that the normalized phase inflection points within a single period corresponding to the 1×61 Damman grating beam splitter are 0.07716±0.0029, 0.09856±0.0029, 0.11252±0.0029, 0.15532±0.0029, 0.19844±0.0029, 0 0.21697±0.0029, 0.23977±0.0029, 0.29446±0.0029, 0.31228±0.0029, 0.32656±0.0029, 0.37636±0.0029, 0.39461±0.0029, 0.45124±0.0029, 0.49728±0.0029, 0.514 95±0.0029, 0.54975±0.0029, 0.56205±0.0029, 0.596±0.0029, 0.61306±0.0029, 0.63495±0.0029, 0.68362±0.0029, 0.70604±0.0029, 0.71726±0.0029, 0.74445±0.0 029, 0.76736±0.0029, 0.78441±0.0029, 0.80242±0.0029, 0.82258±0.0029, 0.84446±0.0029, 0.85355±0.0029, 0.89768±0.0029, 0.91733±0.0029, 0.97905±0.0029.

[0040] Preferably, the large beam-splitting ratio binary pure-phase one-dimensional Damman grating beam splitter is characterized in that the normalized phase inflection points within the first half-cycle corresponding to the 1×62 Damman grating beam splitter are 0.05957±0.0014, 0.07184±0.0014, 0.0886±0.0014, 0.11394±0.0014, 0.11981±0.0014, and 0.1... 3012±0.0015, 0.143±0.0014, 0.14882±0.0014, 0.15739±0.0015, 0.17504±0.0014, 0.18562±0.0014, 0.19546±0.0014, 0.22507±0.0014, 0.2458±0.0014, 0.25242±0.00 14, 0.2589±0.0014, 0.2714±0.0014, 0.27899±0.0014, 0.28722±0.0014, 0.2933±0.0014, 0.30343±0.0014, 0.31543±0.0014, 0.3222±0.0014, 0.3341±0.0014, 0.34413± 0.0015, 0.35257±0.0015, 0.37347±0.0014, 0.38729±0.0014, 0.40495±0.0014, 0.44004±0.0015, 0.45877±0.0014, 0.47025±0.0014, 0.47998±0.0014, 0.4945±0.0014.

[0041] Preferably, the large beam-splitting ratio binary pure-phase one-dimensional Damman grating beam splitter is characterized in that the normalized phase inflection points within a single period corresponding to the 1×63 Damman grating beam splitter are 0.0136±0.0028, 0.08719±0.0028, 0.15491±0.0028, 0.17346±0.0028, 0.20085±0.0028, and 0.21755±0. 0.0028, 0.23924±0.0028, 0.25878±0.0028, 0.27877±0.0028, 0.30138±0.0028, 0.31366±0.0028, 0.33383±0.0028, 0.35896±0.0028, 0.36944±0.0028, 0.38517±0.0028, 0.4063 4±0.0028, 0.42025±0.0028, 0.43319±0.0028, 0.45318±0.0029, 0.49294±0.0028, 0.52317±0.0028, 0.53109±0.0028, 0.55798±0.0028, 0.60187±0.0029, 0.62051±0.0028, 0.6 5109±0.0028,0.68181±0.0028,0.70239±0.0028,0.73654±0.0028,0.79206±0.0029,0.81273±0.0028,0.85011±0.0028,0.88053±0.0028,0.88866±0.0028,0.90364±0.0028.

[0042] Preferably, the large beam-splitting ratio binary pure-phase one-dimensional Damman grating beam splitter is characterized in that the normalized phase inflection points within the first half-cycle corresponding to the 1×65 Damman grating beam splitter are 0.00931±0.0028, 0.03618±0.0027, 0.09238±0.0028, 0.12779±0.0028, 0.14014±0.0027, 0.15676±0.0027, 0 0.1788±0.0027, 0.19128±0.0028, 0.20546±0.0028, 0.25562±0.0027, 0.26379±0.0027, 0.28603±0.0027, 0.30669±0.0027, 0.33032±0.0027, 0.35751±0.0028, 0.37581±0.0028, 0.4020 7±0.0027, 0.42074±0.0027, 0.46928±0.0027, 0.48224±0.0027, 0.51131±0.0027, 0.52836±0.0027, 0.53708±0.0027, 0.60399±0.0028, 0.63457±0.0027, 0.65119±0.0027, 0.70665±0. 0027, 0.72378±0.0028, 0.73778±0.0027, 0.76395±0.0027, 0.81034±0.0027, 0.8283±0.0027, 0.88521±0.0028, 0.90701±0.0027, 0.95525±0.0028, 0.96837±0.0027, 0.98849±0.0027.

[0043] Preferably, the large beam-splitting ratio binary pure-phase one-dimensional Damman grating beam splitter is characterized in that the normalized phase inflection points in the first half-cycle corresponding to the 1×67 Damman grating beam splitter are 0.00759±0.0027, 0.03413±0.0028, 0.08778±0.0027, 0.12363±0.0027, 0.14121±0.0027, 0.15644±0.0027, 0 0.17491±0.0028, 0.19126±0.0027, 0.20366±0.0029, 0.25226±0.0028, 0.26274±0.0027, 0.28215±0.0027, 0.30741±0.0027, 0.32895±0.0028, 0.35527±0.0027, 0.37347±0.0027, 0.402 17±0.0027, 0.41946±0.0027, 0.4656±0.0027, 0.48451±0.0027, 0.50932±0.0027, 0.52578±0.0027, 0.53359±0.0027, 0.60285±0.0027, 0.63577±0.0027, 0.64744±0.0027, 0.70224±0. 0027, 0.72544±0.0027, 0.73902±0.0027, 0.75803±0.0027, 0.8097±0.0027, 0.82732±0.0027, 0.88415±0.0027, 0.90607±0.0028, 0.95522±0.0027, 0.96938±0.0028, 0.98539±0.0027.

[0044] Preferably, the large beam-splitting ratio binary pure-phase one-dimensional Damman grating beam splitter is characterized in that the normalized phase inflection points in the first half-cycle corresponding to the 1×128 Damman grating beam splitter are 0.00191±0.001, 0.00977±0.001, 0.04339±0.001, 0.04709±0.001, 0.05787±0.001, 0.06348±0.001, 0.07905±0.001, 0.08989±0.001, 0.09759±0.001, 0.10884±0.001, 0.11376±0.001, 0.12158±0.001, 0.12919±0.001, 0.1 3378±0.001, 0.13848±0.001, 0.14222±0.001, 0.14621±0.001, 0.1498±0.001, 0.16323±0.001, 0.16791±0.001, 0.17084±0.001, 0.17601±0.001, 0.1 7962±0.001, 0.1842±0.001, 0.1856±0.001, 0.18944±0.001, 0.19522±0.001, 0.19856±0.001, 0.20364±0.001, 0.20824±0.001, 0.21259±0.001, 0.21 879±0.001, 0.22244±0.001, 0.22937±0.001, 0.24036±0.001, 0.24519±0.001, 0.25024±0.001, 0.26333±0.001, 0.27003±0.001, 0.29323±0.001, 0. 30015±0.001, 0.30156±0.001, 0.31166±0.001, 0.3159±0.001, 0.3193±0.001, 0.33177±0.001, 0.33594±0.001, 0.3525±0.001, 0.35869±0.001, 0.36 208±0.001, 0.36986±0.001, 0.37511±0.001, 0.38223±0.001, 0.38628±0.001, 0.39041±0.001, 0.39567±0.001, 0.40034±0.001, 0.40507±0.001, 0.4 0832±0.001,0.41296±0.001,0.41797±0.001,0.42397±0.001,0.43363±0.001,0.44702±0.001,0.46145±0.001,0.46687±0.001,0.47297±0.001,0.4782±0.001, 0.48398±0.001, 0.49303±0.001.

[0045] A high beam splitter with binary pure phase two-dimensional Damman gratings is provided. The two-dimensional phase distribution is formed by the cross-superposition of the phase distributions of two one-dimensional Damman gratings with an included angle α between the grating vectors, where 0° < α ≤ 90°. The specific superposition rule of the two-dimensional Damman gratings is that the overlapping region of the 0 phase and 0 phase of the two one-dimensional Damman gratings is the 0 phase, the overlapping region of the 0 phase and π phase is the π phase, the overlapping region of the π phase and 0 phase is the π phase, and the overlapping region of the π phase and π phase is the 0 phase. That is, the phase distribution of the formed two-dimensional pure phase Damman grating is still a 0-π binary phase distribution.

[0046] Technical effects of the present invention:

[0047] 1) Compared to previous technologies, numerical solutions for the 0 and π phase transition points of large-scale beam splitting Damman gratings from 1×33 to 1×63, as well as 1×65, 1×67 and 1×128, have been further published, which further expands the application of Damman gratings, especially large-scale Damman gratings, in structured light three-dimensional measurement, optical computing, optical interconnection and other fields.

[0048] 2) By cross-superimposing at a certain angle, a two-dimensional large-scale split-beam Damman grating can be realized by any two pairs of the above combinations, and the two-dimensional arrays have a certain angle between them. Attached image description:

[0049] Figure 1 A schematic diagram of the phase inflection point distribution within one period of an odd-numbered one-dimensional Damman grating.

[0050] Figure 2 A schematic diagram of the phase inflection point distribution within one period of an even-numbered one-dimensional Damman grating.

[0051] Figure 3 Histogram of light intensity distribution at each order of a 1×62 array of Vidama gratings.

[0052] Figure 4 Numerical simulation results of a 34×34 orthogonal two-dimensional Damman grating and far-field diffraction spot distribution (α=90°).

[0053] Figure 5 Numerical simulation results of a 40×35 non-orthogonal two-dimensional Damman grating and far-field diffraction spot distribution (α=60°).

[0054] Figure 6 A schematic diagram of the structure within a unit period of a 1×35 Daman grating with relief.

[0055] Figure 7 Schematic diagram of a metasurface two-dimensional Damman grating structure. Detailed Implementation

[0056] Please refer to the appendix. Figure 1 The one-dimensional phase cross-sectional distribution of the Dammann grating, where the phase inflection point is {x}. n}, n=0,1,2,...,N+1, where x0=0,x N+1 =1. According to scalar diffraction theory, the far-field diffraction intensity distribution of a Vidman grating can be written as:

[0057]

[0058] Where m is the diffraction order, x n This represents the nth phase inflection point. Substitute the calculated light intensity into the evaluation function:

[0059]

[0060] Among them, I m Let m represent the m-th diffraction order. Substituting the random initial inflection point array into the light intensity formula and calculating the evaluation function, the numerical solution can be obtained by optimization using the compression factor particle swarm optimization algorithm.

[0061] Considering the practical applications of Damman gratings, the optimization criteria also need to consider: maximizing diffraction efficiency η, maximizing beam splitting uniformity uni, and maximizing the minimum linewidth Δx between normalized phase inflection points. Here, diffraction efficiency η, uniformity uni, and minimum normalized linewidth Δx are defined as follows:

[0062]

[0063]

[0064] Δx=min(x n+1 -x n )

[0065] Based on the above optimizations, Table 1 provides the numerical solutions and corresponding tolerances for the phase transition points of large-scale split-beam Damman gratings from 1×33 to 1×63, as well as 1×65, 1×67, and 1×128. In addition, the corresponding diffraction efficiency, uniformity, and feature size are also listed in the table.

[0066] Table 1 Numerical solutions for the Damman grating

[0067]

[0068]

[0069]

[0070]

[0071]

[0072]

[0073]

[0074]

[0075]

[0076]

[0077]

[0078]

[0079] (I) Example 1: Surface relief 1×35 Daman grating.

[0080] The following is a specific implementation scheme based on a traditional 1×35 Damman grating with a working wavelength of 1064nm solid-state laser.

[0081] The substrate material is fused silica glass. First, a 1×35 photomask is designed as follows: Figure 6 As shown in the left figure, the grating period is designed to be 100 μm, corresponding to a minimum linewidth of approximately 1.5 μm. The left figure shows the phase distribution within one period, where black represents the 0 phase and white represents the π phase; the right figure shows the shape distribution of the surface relief grating within one period, from which it can be seen that there are 10 grating ridges in one period; the corresponding grating ridge height in the figure is d = 1183 nm. The dimensions of the 10 grating ridges in the figure are 1.477μm, 3.791μm, 6.874μm, 2.571μm, 4.24μm, 1.784μm, 4.587μm, 9.221μm, 5.173μm, and 2.76μm, respectively; the dimensions of the 10 grating slots are 5.829μm, 4.474μm, 3.209μm, 4.945μm, 8.109μm, 3.617μm, 13.712μm, 8.69μm, 2.595μm, and 2.342μm, respectively. The surface relief grating is fabricated by forming a photoresist pattern on fused silica glass using a laser direct writing method, then forming an aluminum mask through a lift-off process, and finally transferring the grating surface relief structure using a standard ion etching method to complete the grating fabrication.

[0082] (II) Example 2: Metasurface 40×40 Damman grating.

[0083] The following is a specific implementation scheme based on a metasurface 40×40 polarization-independent Dammann grating, taking a 532nm laser as an example.

[0084] like Figure 7 As shown, the left figure illustrates the phase distribution within one period, where black represents the 0 phase and white represents the π phase. The substrate material is fused silica glass. The right figure shows the basic unit structure of the metasurface, using titanium dioxide cylinders as the basic unit. The period in both directions is p = 250 nm. The 0 phase corresponds to a cylinder diameter of 106.3 nm, and the π phase corresponds to a cylinder diameter of 80.9 nm. The cylinder height is h = 600 nm. Using these two basic units, the left... Figure 2 The phase distribution is shown, with a phase period of 200 μm. The corresponding 0-phase region is the black area in the diagram, and the corresponding π-phase region is the white area in the diagram. The phase distribution is obtained by dividing the corresponding size by 0.25 μm and rounding down. The designed metasurface Damman grating can be fabricated by direct electron beam writing combined with reactive ion etching.

[0085] The large-scale Dammann grating beam splitter disclosed above represents only two specific embodiments of the present invention and should not be construed as limiting the scope of protection of the present invention. It should be noted that those skilled in the art can make several non-inventive modifications and improvements to the specific implementation details proposed in this patent without departing from the basic idea of ​​the present invention, and these modifications and improvements all fall within the scope of protection of the present invention.

[0086] In summary, this invention proposes a large-scale Damman grating beamsplitter with beam splitting scales covering 1×33 to 1×63, as well as 1×65, 1×67 and 1×128. By cross-superimposing two one-dimensional gratings, large-scale two-dimensional Damman beamsplitters can be realized by any pairwise combination of the above-mentioned beams. It can be widely used in fields such as laser structured light, optical computing and optical interconnects.

Claims

1. A high beam splitting ratio binary pure phase Vidamaman grating beam splitter, characterized in that: The high beam-splitting ratio binary pure-phase Damman grating beam splitter is a pure-phase element; there are N phase delays of 0° and 0° within each grating period. Alternating mutation regions, where N is a positive integer greater than 10; 0, The boundary coordinates of the alternating abrupt change region divided by the grating period are defined as the normalized phase inflection point, denoted as {x}. n }, where n = 0, 1, 2, ..., N+1, and x0 = 0, x0 < x1 < x2... < x N+1 x N+1 =1; The normalized minimum linewidth of the large beam-splitting ratio binary pure-phase Damman grating satisfies ,in, The operating wavelength corresponding to the Dammann grating. For the grating period; Let n be the minimum linewidth of the Dammann grating, where n = 0, 1, 2, ...N; The normalized phase inflection points within a single period for the 1×33 Damman grating beam splitter are 0.03746±0.0041, 0.06314±0.004, 0.09628±0.0039, 0.14396±0.004, 0.16501±0.0039, 0.25524±0.004, 0.29977±0.004, 0.37625±0.004, 0.42607±0.0039, 0.55078±0.0044, 0.66772±0.0039, 0.69421±0.004, 0.74751±0.0039, and 0.78299±0.0041, respectively. 0.82667±0.0039, 0.87814±0.004, 0.89979±0.0039; or The normalized phase inflection points within the first half-cycle of the 1×34 Damman grating beam splitter are 0.03417±0.002, 0.09451±0.0019, 0.11439±0.002, 0.16201±0.002, 0.1719±0.002, 0.19444±0.002, 0.21301±0.002, 0.22361±0.0019, 0.24276±0.0019, 0.25366±0.0022, 0.30238±0.0019, 0.32675±0.0019, 0.3548±0.002, and 0.37162±0.0022, respectively. 0.39092±0.0019, 0.40727±0.002, 0.46128±0.0019, 0.48783±0.0019; or The normalized phase inflection points within a single period for the 1×35 Damman grating beam splitter are 0.01784±0.0038, 0.05401±0.0039, 0.09641±0.0038, 0.1775±0.0038, 0.20321±0.0038, 0.25266±0.0039, 0.3214±0.0038, 0.35349±0.0039, 0.3914±0.0038, 0.43614±0.0038, 0.45091±0.0038, 0.5092±0.0038, 0.5368±0.0038, and 0.56022±0.0039, respectively. 0.61195±0.0038, 0.6379±0.0038, 0.73011±0.0038, 0.81701±0.0038, 0.86288±0.0038; or The normalized phase inflection points within the first half-cycle of the 1×36 Damman grating beam splitter are 0.00865±0.002, 0.02722±0.0019, 0.03931±0.0022, 0.05582±0.0019, 0.07379±0.0019, 0.12769±0.0019, 0.14151±0.0019, 0.19101±0.002, 0.21552±0.0019, 0.23528±0.002, 0.25949±0.0019, 0.27766±0.0019, 0.29489±0.002, and 0.31323±0.002, respectively. 0.34737±0.002, 0.42404±0.0019, 0.46445±0.0019, 0.48124±0.0019; or The normalized phase inflection points within a single period for the 1×37 Damman grating beam splitter are 0.04016±0.0037, 0.06173±0.0037, 0.08602±0.0037, 0.12329±0.0037, 0.22432±0.0037, 0.24267±0.0037, 0.37728±0.0038, 0.47121±0.0038, 0.49537±0.0037, 0.53283±0.0038, 0.60207±0.0037, 0.68156±0.0037, 0.72064±0.0038, and 0.74909±0.0038, respectively. 0.78161±0.0037, 0.81556±0.0037, 0.88177±0.0037, 0.91847±0.0037, 0.96111±0.0039; or The normalized phase inflection points within the first half-cycle of the 1×38 Damman grating beam splitter are 0.01777±0.0019, 0.03208±0.0018, 0.07474±0.0019, 0.08652±0.0019, 0.1048±0.0018, 0.11627±0.0018, 0.14619±0.0018, 0.16854±0.0018, 0.20175±0.0019, 0.22956±0.0018, 0.24944±0.0019, 0.26906±0.0018, 0.27856±0.0019, and 0.29614±0.0018, respectively. 0.30917±0.0019, 0.32948±0.0018, 0.3397±0.0019, 0.40522±0.002, 0.46115±0.0018, 0.48922±0.0019; or The normalized phase inflection points within a single period corresponding to the 1×39 Damman grating beam splitter are 0.02682±0.0036, 0.057±0.0036, 0.10664±0.0036, 0.16312±0.0036, 0.21146±0.0036, 0.24267±0.0036, 0.2712±0.0036, 0.29581±0.0036, 0.32456±0.0036, 0.4039±0.0036, 0.44899±0.0036, 0.4699±0.0036, 0.499±0.0036, and 0.51157±0.0036, respectively. 0.54344±0.0036, 0.72421±0.0036, 0.75491±0.0036, 0.78948±0.0036, 0.81117±0.0036, 0.86579±0.0037, 0.95429±0.0036; or The normalized phase inflection points within the first half-cycle of the 1×40 Dammann grating beam splitter are 0.01633±0.0018, 0.04399±0.0019, 0.06307±0.0018, 0.15185±0.0018, 0.17115±0.0019, 0.18231±0.0018, 0.21982±0.0019, 0.25178±0.0018, 0.29613±0.0018, 0.31111±0.0018, 0.32837±0.0018, 0.34921±0.0018, 0.36364±0.0018, and 0.37688±0.0019, respectively. 0.39274±0.0018, 0.40334±0.0018, 0.41743±0.0018, 0.43167±0.0019, 0.4669±0.0018, 0.48846±0.0019; or The normalized phase inflection points within a single period for the 1×41 Damman grating beam splitter are 0.0603±0.0036, 0.10366±0.0036, 0.17873±0.0036, 0.20972±0.0036, 0.25728±0.0036, 0.28773±0.0036, 0.31798±0.0036, 0.34881±0.0037, 0.38048±0.0036, 0.41375±0.0036, 0.43251±0.0036, 0.44594±0.0035, 0.47801±0.0036, and 0.51213±0.0036, respectively. 0.53908±0.0036, 0.65661±0.0036, 0.79506±0.0036, 0.83194±0.0035, 0.92013±0.0036, 0.94966±0.0035, 0.97102±0.0036; or The normalized phase inflection points within the first half-cycle of the 1×42 Damman grating beam splitter are 0.04238±0.0018, 0.11207±0.0018, 0.11741±0.0018, 0.14118±0.0018, 0.15767±0.0018, 0.1755±0.0018, 0.1951±0.0018, 0.21351±0.0018, 0.22589±0.0018, 0.23632±0.0018, 0.25487±0.0018, 0.26141±0.0018, 0.27763±0.0018, and 0.29214±0.0018, respectively. 0.32471±0.0018, 0.34174±0.0018, 0.35378±0.0018, 0.36695±0.0018, 0.40868±0.0018, 0.43455±0.0018, 0.46831±0.0018, 0.48377±0.0018; or The normalized phase inflection points within a single period corresponding to the 1×43 Damman grating beam splitter are 0.03213±0.0034, 0.07242±0.0034, 0.09176±0.0035, 0.13285±0.0034, 0.18249±0.0035, 0.19474±0.0034, 0.22954±0.0034, 0.25696±0.0035, 0.2826±0.0034, 0.3124±0.0034, 0.3371±0.0034, 0.3641±0.0035, 0.38376±0.0035, and 0.41763±0.0034, respectively. 0.43024±0.0034, 0.45568±0.0035, 0.50905±0.0035, 0.54023±0.0035, 0.58352±0.0035, 0.63013±0.0035, 0.67042±0.0034, 0.74348±0.0034, 0.8197±0.0034; or The normalized phase inflection points within the first half-cycle of the 1×44 Damman grating beam splitter are 0.07589±0.0017, 0.08702±0.0017, 0.10605±0.0017, 0.12232±0.0017, 0.14316±0.0017, 0.17938±0.0017, 0.20112±0.0017, 0.2206±0.0017, 0.26384±0.0017, 0.27373±0.0019, 0.27892±0.0017, 0.29849±0.0017, 0.31212±0.0017, and 0.32305±0.0017, respectively. 0.33733±0.0017, 0.34839±0.0017, 0.36318±0.0017, 0.37651±0.0017, 0.40782±0.0018, 0.42604±0.0017, 0.4334±0.0017, 0.46±0.0018, 0.47963±0.0017, 0.48789±0.0017; or The normalized phase inflection points within a single period for the 1×45 Dammann grating beam splitter are 0.0278±0.0033, 0.07401±0.0033, 0.09532±0.0033, 0.15294±0.0033, 0.17034±0.0033, 0.19929±0.0033, 0.23554±0.0033, 0.30226±0.0035, 0.42237±0.0033, 0.48182±0.0033, 0.50948±0.0033, 0.53421±0.0033, 0.55948±0.0034, and 0.5831±0.0034, respectively. 0.62261±0.0033, 0.6323±0.0034, 0.67915±0.0033, 0.70412±0.0033, 0.74771±0.0033, 0.76294±0.0033, 0.77853±0.0033, 0.80452±0.0033, 0.87826±0.0033, 0.90494±0.0033, 0.97563±0.0033; or The normalized phase inflection points within the first half-cycle of the 1×46 Damman grating beam splitter are 0.0341±0.0017, 0.05074±0.0017, 0.0634±0.0017, 0.08217±0.0017, 0.09021±0.0017, 0.11317±0.0017, 0.15209±0.0017, 0.16455±0.0017, 0.17821±0.0017, 0.1889±0.0017, 0.20249±0.0017, 0.21426±0.0017, 0.22316±0.0017, and 0.25489±0.0017, respectively. 0.29581±0.0017, 0.31154±0.0017, 0.33542±0.0017, 0.34461±0.0017, 0.40145±0.0017, 0.4139±0.0017, 0.4245±0.0017, 0.43842±0.0018, 0.4653±0.0017, 0.48877±0.0018; or The normalized phase inflection points within a single period corresponding to the 1×47 Damman grating beam splitter are 0.03143±0.0033, 0.04881±0.0033, 0.11615±0.0033, 0.12793±0.0033, 0.16221±0.0033, 0.18225±0.0033, 0.21706±0.0033, 0.24967±0.0034, 0.27165±0.0033, 0.30627±0.0033, 0.32688±0.0033, 0.39725±0.0033, 0.45685±0.0033, and 0.55025±0.0033, respectively. 0.57259±0.0033, 0.63549±0.0033, 0.67592±0.0033, 0.70412±0.0033, 0.74771±0.0033, 0.82164±0.0033, 0.83367±0.0033, 0.86435±0.0033, 0.88681±0.0034, 0.91242±0.0033, 0.93608±0.0034; or The normalized phase inflection points within the first half-cycle of the 1×48 Damman grating beam splitter are 0.01764±0.0018, 0.04726±0.0017, 0.05392±0.0016, 0.06795±0.0016, 0.07992±0.0017, 0.1058±0.0016, 0.13484±0.0016, 0.15133±0.0016, 0.17516±0.0016, 0.18854±0.0016, 0.20632±0.0016, 0.21501±0.0017, 0.22871±0.0016, and 0.24216±0.0016, respectively. 0.25191±0.0017, 0.26153±0.0016, 0.2741±0.0017, 0.28841±0.0017, 0.29698±0.0016, 0.31961±0.0017, 0.33523±0.0016, 0.34907±0.0016, 0.35712±0.0016, 0.40023±0.0016, 0.42874±0.0016, 0.49218±0.0017; or The normalized phase inflection points within a single period for the 1×49 Damman grating beam splitter are 0.02577±0.0032, 0.0562±0.0031, 0.13073±0.0032, 0.1848±0.0032, 0.19812±0.0032, 0.22684±0.0032, 0.2828±0.0032, 0.30572±0.0032, 0.3377±0.0032, 0.36034±0.0032, 0.38761±0.0032, 0.40562±0.0032, 0.4333±0.0032, and 0.44855±0.0032, respectively. 0.4684±0.0032, 0.56061±0.0032, 0.58145±0.0032, 0.65504±0.0031, 0.67505±0.0032, 0.72478±0.0031, 0.76108±0.0032, 0.78718±0.0032, 0.80405±0.0032, 0.82812±0.0032, 0.88167±0.0032, 0.94622±0.0032, 0.95951±0.0032; or The normalized phase inflection points within the first half-cycle of the 1×50 Damman grating beam splitter are 0.0123±0.0016, 0.03103±0.0016, 0.05887±0.0016, 0.06863±0.0016, 0.08271±0.0016, 0.08921±0.0016, 0.09706±0.0016, 0.11025±0.0016, 0.12228±0.0016, 0.13541±0.0016, 0.14967±0.0016, 0.17261±0.0016, 0.18078±0.0016, and 0.19821±0.0016, respectively. 0.21408±0.0016, 0.24799±0.0016, 0.2645±0.0016, 0.27629±0.0016, 0.28382±0.0016, 0.321±0.0016, 0.33411±0.0016, 0.37321±0.0017, 0.38744±0.0016, 0.39604±0.0016, 0.44371±0.0016, 0.47268±0.0016, 0.47998±0.0016, 0.49416±0.0016; or The normalized phase inflection points within a single period for the 1×51 Damman grating beam splitter are 0.03409±0.0032, 0.11826±0.0032, 0.1526±0.0033, 0.18045±0.0032, 0.19719±0.0032, 0.22504±0.0032, 0.2456±0.0031, 0.25958±0.0032, 0.28576±0.0032, 0.31034±0.0032, 0.33396±0.0032, 0.37632±0.0032, 0.40159±0.0032, and 0.46093±0.0032, respectively. 0.48918±0.0032, 0.51209±0.0032, 0.53348±0.0032, 0.59998±0.0032, 0.61423±0.0032, 0.67338±0.0032, 0.72227±0.0032, 0.78298±0.0032, 0.79754±0.0032, 0.83655±0.0032, 0.92991±0.0032, 0.94903±0.0032, 0.98478±0.0031; or The normalized phase inflection points within the first half-cycle of the 1×52 Damman grating beam splitter are 0.00915±0.0016, 0.02524±0.0016, 0.03437±0.0016, 0.05272±0.0016, 0.06629±0.0016, 0.11232±0.0016, 0.12262±0.0016, 0.13609±0.0016, 0.14444±0.0016, 0.1558±0.0016, 0.16654±0.0016, 0.17846±0.0016, 0.19024±0.0016, and 0.21521±0.0015, respectively. 0.23115±0.0016, 0.23736±0.0016, 0.26537±0.0016, 0.27746±0.0016, 0.28833±0.0016, 0.32824±0.0015, 0.33942±0.0016, 0.37954±0.0016, 0.40611±0.0016, 0.41538±0.0016, 0.43234±0.0016, 0.46227±0.0016, 0.48427±0.0016, 0.49377±0.0016; or The normalized phase inflection points within a single period corresponding to the 1×53 Damman grating beam splitter are 0.03368±0.0031, 0.07234±0.0031, 0.09549±0.0031, 0.12323±0.0031, 0.15079±0.0031, 0.17732±0.0031, 0.19698±0.0031, 0.21764±0.0031, 0.24288±0.0031, 0.25635±0.0031, 0.28071±0.0031, 0.30321±0.0031, 0.36779±0.0032, and 0.38478±0.0031, respectively. 0.39936±0.0031, 0.41449±0.0031, 0.44228±0.0031, 0.46676±0.0031, 0.5433±0.0031, 0.56996±0.0031, 0.60419±0.0031, 0.65867±0.0031, 0.67446±0.0031, 0.69185±0.0031, 0.78585±0.0031, 0.79469±0.0031, 0.82192±0.0031, 0.85748±0.0031, 0.91005±0.0031; or The normalized phase inflection points within the first half-cycle of the 1×54 Damman grating beam splitter are 0.03119±0.0015, 0.06352±0.0015, 0.10765±0.0015, 0.11301±0.0015, 0.12471±0.0015, 0.13717±0.0015, 0.15267±0.0015, 0.16434±0.0015, 0.18488±0.0015, 0.19914±0.0015, 0.2356±0.0015, 0.2508±0.0015, 0.27122±0.0015, and 0.28978±0.0015, respectively. 0.2951±0.0015, 0.31184±0.0015, 0.31769±0.0015, 0.32851±0.0015, 0.33983±0.0016, 0.35007±0.0015, 0.36681±0.0015, 0.37606±0.0016, 0.40766±0.0015, 0.41872±0.0015, 0.44354±0.0015, 0.45125±0.0015, 0.46315±0.0015, 0.47364±0.0015, 0.48245±0.0015, 0.49314±0.0015; or The normalized phase inflection points within a single period corresponding to the 1×55 Damman grating beam splitter are 0.01411±0.003, 0.03817±0.003, 0.06309±0.0031, 0.08238±0.003, 0.09492±0.003, 0.1215±0.003, 0.1742±0.003, 0.18615±0.003, 0.24689±0.0031, 0.26844±0.0031, 0.28999±0.003, 0.31558±0.003, 0.35015±0.003, and 0.39596±0.003, respectively. 0.42063±0.0031, 0.45663±0.003, 0.47393±0.0031, 0.48824±0.003, 0.53086±0.0031, 0.6061±0.003, 0.63002±0.0033, 0.66144±0.0031, 0.68666±0.003, 0.70632±0.003, 0.77363±0.003, 0.81727±0.003, 0.93478±0.003, 0.95883±0.0031, 0.97961±0.0031; or The normalized phase inflection points within the first half-cycle of the 1×56 Damman grating beam splitter are 0.03037±0.0015, 0.04334±0.0015, 0.05786±0.0015, 0.07233±0.0015, 0.08268±0.0015, 0.11851±0.0015, 0.13525±0.0015, 0.14171±0.0015, 0.17017±0.0015, 0.17511±0.0015, 0.20734±0.0015, 0.21798±0.0015, 0.22902±0.0015, and 0.23774±0.0015, respectively. 0.26128±0.0015, 0.27297±0.0015, 0.29838±0.0015, 0.33079±0.0015, 0.35634±0.0016, 0.36644±0.0015, 0.37839±0.0015, 0.40739±0.0015, 0.41308±0.0015, 0.42112±0.0015, 0.43627±0.0015, 0.44791±0.0015, 0.45749±0.0016, 0.47275±0.0015, 0.48026±0.0015, 0.48979±0.0015; or The normalized phase inflection points within a single period corresponding to the 1×57 Damman grating beam splitter are 0.05358±0.0029, 0.0645±0.003, 0.08278±0.0029, 0.10281±0.003, 0.12334±0.003, 0.15895±0.003, 0.19198±0.003, 0.2169±0.003, 0.23974±0.003, 0.28842±0.003, 0.32374±0.003, 0.34966±0.003, 0.36981±0.003, and 0.38744±0.003, respectively. 0.40677±0.003, 0.42388±0.0029, 0.44956±0.003, 0.46989±0.003, 0.48469±0.003, 0.52459±0.003, 0.53525±0.003, 0.5718±0.003, 0.59152±0.003, 0.678±0.003, 0.70008±0.003, 0.76554±0.003, 0.81202±0.003, 0.83301±0.003, 0.89889±0.003, 0.91724±0.003, 0.93016±0.003; or The normalized phase inflection points within the first half-cycle of the 1×58 Damman grating beam splitter are 0.06957±0.0015, 0.11211±0.0015, 0.12826±0.0015, 0.13323±0.0015, 0.14257±0.0015, 0.16134±0.0015, 0.17341±0.0015, 0.17941±0.0015, 0.19376±0.0015, 0.20943±0.0015, 0.22152±0.0015, 0.2278±0.0015, 0.24292±0.0015, and 0.24901±0.0015, respectively. 0.25399±0.0015, 0.2682±0.0015, 0.27693±0.0015, 0.28915±0.0015, 0.2973±0.0015, 0.30779±0.0015, 0.31783±0.0015, 0.32417±0.0015, 0.33541±0.0015, 0.34811±0.0016, 0.36756±0.0015, 0.3766±0.0016, 0.38745±0.0015, 0.41051±0.0015, 0.42515±0.0016, 0.44435±0.0015, 0.45732±0.0015, 0.48641±0.0015; or The normalized phase inflection points within a single period corresponding to the 1×59 Damman grating beam splitter are 0.01838±0.0029, 0.03824±0.0029, 0.05983±0.0029, 0.08159±0.0029, 0.09423±0.0029, 0.11482±0.0029, 0.12857±0.0029, 0.13899±0.0029, 0.17073±0.0029, 0.19491±0.0029, 0.23307±0.0029, 0.25466±0.0029, 0.30714±0.0029, and 0.32191±0.0029, respectively. 0.33256±0.0029, 0.37908±0.0029, 0.41131±0.0029, 0.47268±0.0029, 0.48564±0.0029, 0.54678±0.0029, 0.55792±0.0029, 0.59037±0.0029, 0.60812±0.0029, 0.62428±0.0029, 0.65035±0.0029, 0.68508±0.0029, 0.71502±0.0029, 0.73572±0.0029, 0.75517±0.0029, 0.82427±0.0029, 0.84642±0.0029, 0.86645±0.0029, 0.93805±0.0029; or The normalized phase inflection points within the first half-cycle of the 1×60 Damman grating beam splitter are 0.02422±0.0015, 0.04156±0.0015, 0.05603±0.0015, 0.08577±0.0015, 0.09113±0.0015, 0.09968±0.0015, 0.11925±0.0015, 0.12893±0.0015, 0.14095±0.0015, 0.15321±0.0015, 0.17625±0.0015, 0.18646±0.0015, 0.19669±0.0015, and 0.20451±0.0015, respectively. 0.21367±0.0015, 0.22646±0.0015, 0.23286±0.0015, 0.24531±0.0015, 0.25719±0.0015, 0.2635±0.0015, 0.30856±0.0015, 0.31481±0.0015, 0.3259±0.0015, 0.34218±0.0015, 0.37597±0.0015, 0.38804±0.0015, 0.41135±0.0015, 0.42044±0.0015, 0.43266±0.0015, 0.47128±0.0014, 0.47903±0.0015, 0.48558±0.0015; or The normalized phase inflection points within a single period for the 1×61 Damman grating beam splitter are 0.07716±0.0029, 0.09856±0.0029, 0.11252±0.0029, 0.15532±0.0029, 0.19844±0.0029, 0.21697±0.0029, 0.23977±0.0029, 0.29446±0.0029, 0.31228±0.0029, 0.32656±0.0029, 0.37636±0.0029, 0.39461±0.0029, 0.45124±0.0029, and 0.49728±0.0029, respectively. 0.51495±0.0029, 0.54975±0.0029, 0.56205±0.0029, 0.596±0.0029, 0.61306±0.0029, 0.63495±0.0029, 0.68362±0.0029, 0.70604±0.0029, 0.71726±0.0029, 0.74445±0.0029, 0.76736±0.0029, 0.78441±0.0029, 0.80242±0.0029, 0.82258±0.0029, 0.84446±0.0029, 0.85355±0.0029, 0.89768±0.0029, 0.91733±0.0029, 0.97905±0.0029; or The normalized phase inflection points within the first half-cycle of the 1×62 Damman grating beam splitter are 0.05957±0.0014, 0.07184±0.0014, 0.0886±0.0014, 0.11394±0.0014, 0.11981±0.0014, 0.13012±0.0015, 0.143±0.0014, 0.14882±0.0014, 0.15739±0.0015, 0.17504±0.0014, 0.18562±0.0014, 0.19546±0.0014, 0.22507±0.0014, and 0.2458±0.0014, respectively. 0.25242±0.0014, 0.2589±0.0014, 0.2714±0.0014, 0.27899±0.0014, 0.28722±0.0014, 0.2933±0.0014, 0.30343±0.0014, 0.31543±0.0014, 0.3222±0.0014, 0.3341±0.0014, 0.34413±0.0015, 0.35257±0.0015, 0.37347±0.0014, 0.38729±0.0014, 0.40495±0.0014, 0.44004±0.0015, 0.45877±0.0014, 0.47025±0.0014, 0.47998±0.0014, 0.4945±0.0014; or The normalized phase inflection points within a single period for the 1×63 Damman grating beam splitter are 0.0136±0.0028, 0.08719±0.0028, 0.15491±0.0028, 0.17346±0.0028, 0.20085±0.0028, 0.21755±0.0028, 0.23924±0.0028, 0.25878±0.0028, 0.27877±0.0028, 0.30138±0.0028, 0.31366±0.0028, 0.33383±0.0028, 0.35896±0.0028, and 0.36944±0.0028, respectively. 0.38517±0.0028, 0.40634±0.0028, 0.42025±0.0028, 0.43319±0.0028, 0.45318±0.0029, 0.49294±0.0028, 0.52317±0.0028, 0.53109±0.0028, 0.55798±0.0028, 0.60187±0.0029, 0.62051±0.0028, 0.65109±0.0028, 0.68181±0.0028, 0.70239±0.0028, 0.73654±0.0028 0.79206±0.0029, 0.81273±0.0028, 0.85011±0.0028, 0.88053±0.0028, 0.88866±0.0028, 0.90364±0.0028; or The normalized phase inflection points within the first half-cycle of the 1×65 Damman grating beam splitter are 0.00931±0.0028, 0.03618±0.0027, 0.09238±0.0028, 0.12779±0.0028, 0.14014±0.0027, 0.15676±0.0027, 0.1788±0.0027, 0.19128±0.0028, 0.20546±0.0028, 0.25562±0.0027, 0.26379±0.0027, 0.28603±0.0027, 0.30669±0.0027, and 0.33032±0.0027, respectively. 0.35751±0.0028, 0.37581±0.0028, 0.40207±0.0027, 0.42074±0.0027, 0.46928±0.0027, 0.48224±0.0027, 0.51131±0.0027, 0.52836±0.0027, 0.53708±0.0027, 0.60399±0.0028, 0.63457±0.0027, 0.65119±0.0027, 0.70665±0.0027, 0.72378±0.0028, 0.73778±0.0027, 0.76395±0.0027, 0.81034±0.0027, 0.8283±0.0027, 0.88521±0.0028, 0.90701±0.0027, 0.95525±0.0028, 0.96837±0.0027, 0.98849±0.0027; or The normalized phase inflection points within the first half-cycle of the 1×67 Damman grating beam splitter are 0.00759±0.0027, 0.03413±0.0028, 0.08778±0.0027, 0.12363±0.0027, 0.14121±0.0027, 0.15644±0.0027, 0.17491±0.0028, 0.19126±0.0027, 0.20366±0.0029, 0.25226±0.0028, 0.26274±0.0027, 0.28215±0.0027, 0.30741±0.0027, and 0.32895±0.0028, respectively. 0.35527±0.0027, 0.37347±0.0027, 0.40217±0.0027, 0.41946±0.0027, 0.4656±0.0027, 0.48451±0.0027, 0.50932±0.0027, 0.52578±0.0027, 0.53359±0.0027, 0.60285±0.0027, 0.63577±0.0027, 0.64744±0.0027, 0.70224±0.0027, 0.72544±0.0027, 0.73902±0.0027 0.75803±0.0027, 0.8097±0.0027, 0.82732±0.0027, 0.88415±0.0027, 0.90607±0.0028, 0.95522±0.0027, 0.96938±0.0028, 0.98539±0.0027; or, The normalized phase inflection points within the first half-cycle of the 1×128 Damman grating beam splitter are 0.00191±0.001, 0.00977±0.001, 0.04339±0.001, 0.04709±0.001, 0.05787±0.001, 0.06348±0.001, 0.07905±0.001, 0.08989±0.001, 0.09759±0.001, 0.10884±0.001, 0.11376±0.001, 0.12158±0.001, 0.12919±0.001, and 0.13378±0.001, respectively. 0.13848±0.001, 0.14222±0.001, 0.14621±0.001, 0.1498±0.001, 0.16323±0.001, 0.16791±0.001, 0.17084±0.001, 0.17601±0.001, 0.17962±0.001, 0.1842±0.001, 0.1856±0.001, 0.18944±0.001, 0.19522±0.001, 0.19856±0.001, 0.20364±0.001, 0.20824±0.001, 0.21259±0.001, 0.21879±0.001, 0.22244±0.001, 0.22937±0.001, 0.24036±0.001, 0.24519±0.001, 0.25024±0.001, 0.26333±0.001, 0.27003±0.001, 0.29323±0.001, 0.30015±0.001, 0.30156±0.001, 0.31166±0.001, 0.3159±0.001, 0.3193±0.001, 0.33177±0.001, 0.33594±0.001, 0.3525±0.001, 0.35869±0.001, 0.36208±0.001, 0.36986±0.001, 0.37511±0.001, 0.38223±0.001, 0.38628±0.001, 0.39041±0.001, 0.39567±0.001, 0.40034±0.001, 0.40507±0.001, 0.40832±0.001, 0.41296±0.001, 0.41797±0.001, 0.42397±0.001, 0.43363±0.001, 0.44702±0.001, 0.46145±0.001, 0.46687±0.001, 0.47297±0.001, 0.4782±0.001, 0.48398±0.001, 0.49303±0.001。.

2. The large beam-splitting ratio binary pure-phase Vidamaman grating beam splitter according to claim 1, characterized in that... The substrate material of the Damman grating has a transmittance greater than 90% in the operating wavelength band; the grating ridge and grating groove are made of two alternating materials in two steps, with the corresponding step depths satisfying... ,in n 1 and n 2 represents the refractive index of the working center wavelength of the ridge and groove of the two materials, respectively.

3. A high beam-splitting ratio binary pure-phase Vidamaman grating beam splitter according to claim 1, characterized in that... The substrate material of the Damman grating has a transmittance greater than 90% in the working wavelength band, and the grating's 0, Binary phase is introduced through metasurface unit structures or the refractive index difference of liquid crystal materials.

4. A high beam-splitting ratio binary pure-phase two-dimensional Damman grating beam splitter, characterized in that, Its two-dimensional phase distribution is formed by the cross-superposition of the phase distributions of the binary pure phase one-dimensional Damman gratings described in any one of claims 1-3, where the included angle α is between two grating vectors, and 0º < α ≤ 90º; the specific superposition rule of the two-dimensional Damman gratings is that the overlapping region of the 0 phases of the two one-dimensional Damman gratings is the 0 phase, and the region corresponding to the 0 phase and the 0 phase is the 0 phase. The phase overlap region is Phase, corresponding The overlapping region of phase and 0 phase is Phase, corresponding Phase and The phase overlap region is 0 phase, meaning the phase distribution of the resulting two-dimensional pure phase Dammann grating is still 0-. Binary phase distribution.

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