{"title":"Calculation of the Transmission Function of a Generalized Spiral Phase Plate to Form a Given Curve","authors":"A. V. Ustinov, V. I. Logachev, S. N. Khonina","doi":"10.3103/S1060992X24700280","DOIUrl":"10.3103/S1060992X24700280","url":null,"abstract":"<p>We consider the inverse diffraction problem for a generalized spiral phase plate. For a given luminous curve in the focal plane, the transmission function of the plate forming this curve is calculated. It is assumed that the curve is specified analytically in polar coordinates in the form of an explicit dependence of the radius on the angle. We give the conditions imposed on the curve under which the problem certainly has a solution. Also there are examples of solving the direct problem when curves that do not satisfy these conditions are formed.</p>","PeriodicalId":721,"journal":{"name":"Optical Memory and Neural Networks","volume":"33 1 supplement","pages":"S34 - S42"},"PeriodicalIF":1.0,"publicationDate":"2024-12-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142811082","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
V. V. Kotlyar, S. S. Stafeev, A. M. Telegin, E. S. Kozlova
{"title":"Spin Hall Effect While Focusing an Optical Vortex and a Plane Wave with Linear Polarisations","authors":"V. V. Kotlyar, S. S. Stafeev, A. M. Telegin, E. S. Kozlova","doi":"10.3103/S1060992X24700243","DOIUrl":"10.3103/S1060992X24700243","url":null,"abstract":"<p>The sharp focusing of the superposition of a plane wave with the linear polarisation (LP) and an optical vortex with topological charge (TC) <i>m</i> and with the same LP directed along the horizontal axis is considered. Applying the Richards–Wolf formalism, analytical formulas are derived for the intensity and the spin angular momentum (SAM) lengthwise component in the focal plane. It is demonstated that for odd and even TCs <i>m</i> the SAM and the intensity have different symmetries: for even <i>m</i> they are symmetric about both Cartesian axes, and for odd <i>m</i> they are symmetric only about the vertical axis. The intensity pattern has 2<i>m</i> local maxima in the focal plane. The intensity on the optical axis for any TC <i>m</i> is nonzero. The pattern of the lengthwise SAM (spin density) in the focal plane has 2(<i>m</i> + 2) subwavelength areas in the half of which the SAM has positive value while in others it has negative value. The centers of these areas alternately lie on a circle of a certain radius with a center on the optical axis. This spin pattern with different signs shows the spin Hall effect in the focal plane. The total negative and positive spin in the focal plane are mutually compensated and equal to zero.</p>","PeriodicalId":721,"journal":{"name":"Optical Memory and Neural Networks","volume":"33 1 supplement","pages":"S1 - S8"},"PeriodicalIF":1.0,"publicationDate":"2024-12-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142811157","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Intertwining Intensity Moments and Orbital Angular Momenta via Astigmatic Transforms of Structured Beams","authors":"A. V. Volyar, E. G. Abramochkin, M. V. Bretsko","doi":"10.3103/S1060992X2470036X","DOIUrl":"10.3103/S1060992X2470036X","url":null,"abstract":"<p>We have shown theoretically and experimentally that for defining the orbital angular momentum (OAM) of structured Laguerre-Gaussian (sLG) beams with a broken symmetry, it is sufficient to measure the only element of the symplectic intensity moment matrix. It looks like an intertwining of two elements belonging to two submatrices of the general symplectic matrix of intensity moments under the condition when the amplitude parameter of the sLG beam is equal to unity. But once slightly to deviate the amplitude parameter from this value, as the intertwining at once unravels. Besides, we revealed that by measuring such a matrix element of the sLG beam in free space enables us to exactly predict the OAM behavior of the sLG beam in a first-order optical system with an astigmatic element, without any measuring in the astigmatic system itself.</p>","PeriodicalId":721,"journal":{"name":"Optical Memory and Neural Networks","volume":"33 1 supplement","pages":"S114 - S122"},"PeriodicalIF":1.0,"publicationDate":"2024-12-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142811228","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Longitudinal Spin Hall Effect of Polarization Vortices with a Carrier Frequency","authors":"V. V. Kotlyar, A. G. Nalimov, A. A. Kovalev","doi":"10.3103/S1060992X24700358","DOIUrl":"10.3103/S1060992X24700358","url":null,"abstract":"<p>We derive the axial projection of the spin angular momentum (SAM) vector for a vector Gaussian beam with 1D periodic amplitude modulation. Such a beam has zero SAM in the source plane and its polarization is inhomogeneous linear. We demonstrate that when such a beam propagates, its periodic modulation effectively splits the beam into two, having elliptic polarization of opposite handedness. Therefore, the spin Hall effect is shown to arise, since the cross section of the beam contains alternating domains with nonzero spin of opposite sign. For generating such a field, a metasurface can be employed, whose transmittance is changing with one coordinate periodically.</p>","PeriodicalId":721,"journal":{"name":"Optical Memory and Neural Networks","volume":"33 1 supplement","pages":"S105 - S113"},"PeriodicalIF":1.0,"publicationDate":"2024-12-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142811075","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
P. A. Khorin, S. K. Sergunin, S. N. Khonina, V. P. Veiko, G. K. Kostyuk, V. A. Shkuratova
{"title":"Simulation of Diffraction on a Stepped Spiral Phase Plate with Radiation of Different Wavelengths in order to Form Optical Vortices of Different Orders","authors":"P. A. Khorin, S. K. Sergunin, S. N. Khonina, V. P. Veiko, G. K. Kostyuk, V. A. Shkuratova","doi":"10.3103/S1060992X24700310","DOIUrl":"10.3103/S1060992X24700310","url":null,"abstract":"<p>The diffraction of a Gaussian beam by a stepped spiral phase plate (SPP) is studied for different wavelengths of laser radiation. Numerically, using the finite difference time domain method, the formation of a vortex beam by a SPP with different number of uniform sectors is shown. The diffraction of laser radiation with a wavelength in the range from 0.5 to 1.5 μm by a SPP with 20 sectors was calculated and the transformation of a Gaussian beam into a vortex beam with different topological charges due to variations in wavelength was shown. To determine the value of the orbital angular momentum (OAM) of the formed vortex beam, the weight spectrum is calculated on the basis of angular harmonics (AH). We estimated the vortex beam quality of an integer order using a multichannel diffractive optical element (DOE), which implements the optical decomposition of the light field according to the AH basis. The detection of vortex beams with 1st, 2nd and 3rd order is shown numerically by matched filtering.</p>","PeriodicalId":721,"journal":{"name":"Optical Memory and Neural Networks","volume":"33 1 supplement","pages":"S65 - S74"},"PeriodicalIF":1.0,"publicationDate":"2024-12-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142811080","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
M. V. Bretsko, S. I. Khalilov, S. I. Yakubov, D. V. Maksimov, A. V. Volyar, Ya. E. Akimova
{"title":"Astigmatic Structured Laguerre-Gaussian Beams: Orbital Angular Momentum and Its Transformation","authors":"M. V. Bretsko, S. I. Khalilov, S. I. Yakubov, D. V. Maksimov, A. V. Volyar, Ya. E. Akimova","doi":"10.3103/S1060992X24700383","DOIUrl":"10.3103/S1060992X24700383","url":null,"abstract":"<p>This paper presents a study of astigmatic structured Laguerre-Gaussian beams (asLG) and their orbital angular momentum (OAM). The complex amplitude of the asLG beam is obtained, which takes into account the distance along the <i>z</i>-axis after the cylindrical lens, as well as the angle of inclination of the cylindrical lens. An expression for the OAM is obtained that depends only on the Hermite-Gaussian mode amplitudes. Computer modeling has been carried out, which is in good agreement with experiment.</p>","PeriodicalId":721,"journal":{"name":"Optical Memory and Neural Networks","volume":"33 1 supplement","pages":"S139 - S145"},"PeriodicalIF":1.0,"publicationDate":"2024-12-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142811158","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
S. I. Yakubov, M. V. Bretsko, S. I. Khalilov, D. V. Maksimov, S. N. Lapaeva, Ya. E. Akimova
{"title":"Formation and Control of the Polarization Structure of Vector Structured Laguerre-Gaussian Beams","authors":"S. I. Yakubov, M. V. Bretsko, S. I. Khalilov, D. V. Maksimov, S. N. Lapaeva, Ya. E. Akimova","doi":"10.3103/S1060992X24700334","DOIUrl":"10.3103/S1060992X24700334","url":null,"abstract":"<p>In this study, experiments were conducted aimed at the formation of both standard Laguerre-Gaussian vector beams and more complex structured Laguerre-Gaussian vector beams using a spatial light modulator. The ability to measure the polarization structure of these beams using a differential Stokes polarimeter was experimentally demonstrated. The obtained measurement data on the polarization distribution successfully correspond to theoretical calculations, which confirms the effectiveness and accuracy of this method in the analysis of optical structures.</p>","PeriodicalId":721,"journal":{"name":"Optical Memory and Neural Networks","volume":"33 1 supplement","pages":"S90 - S97"},"PeriodicalIF":1.0,"publicationDate":"2024-12-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142811230","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Optimization Based on Samples Generated by the Canny Operator of Parameters of Vortex Filter and Ring Filter Used for Optical Edge Selection","authors":"A. S. Khlebodarov","doi":"10.3103/S1060992X24700255","DOIUrl":"10.3103/S1060992X24700255","url":null,"abstract":"<p>Based on the modeling of optical edge selection, studies were conducted to optimize the parameters of spatial filters. The parameters of the ring and vortex spatial filters were optimized for optical edge selection in different images using the Fourier-correlator. The result of the research is the development of an algorithm that helps to find the optimal parameters of ring and vortex spatial filters for a given image. The optimality criterion is determined using Canny’s digital algorithm, therefore, the developed algorithm is a hybrid algorithm. The developed algorithm for finding optimal filter parameters is based on minimizing the standard deviation from the samples formed by the Canny operator. The purpose of the developed algorithm consists of adjusting the Spatial light modulator to the input image in a real experiment. The fact that the vortex filter with optimal parameters is slightly inferior to the Canny’s operator was established. It has been shown that the vortex filter makes it possible to selectively highlight object details.</p>","PeriodicalId":721,"journal":{"name":"Optical Memory and Neural Networks","volume":"33 1 supplement","pages":"S9 - S17"},"PeriodicalIF":1.0,"publicationDate":"2024-12-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142811084","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
S. I. Khalilov, M. V. Bretsko, S. I. Yakubov, S. N. Lapaeva, D. V. Maksimov, A. V. Volyar, Ya. E. Akimova
{"title":"Astigmatic Laguerre–Gaussian Beams with Rapid Oscillations of Orbital Angular Momentum","authors":"S. I. Khalilov, M. V. Bretsko, S. I. Yakubov, S. N. Lapaeva, D. V. Maksimov, A. V. Volyar, Ya. E. Akimova","doi":"10.3103/S1060992X24700449","DOIUrl":"10.3103/S1060992X24700449","url":null,"abstract":"<p>A matrix formalism, denoted as ABCD, has been developed and experimentally implemented to describe structured transformations and the orbital angular momentum of structured Laguerre–Gaussian beams in an astigmatic optical system containing a single cylindrical lens. It is demonstrated that the matrix formalism not only aligns well with the method of integral astigmatic transformations but also significantly broadens the scope of its application.</p>","PeriodicalId":721,"journal":{"name":"Optical Memory and Neural Networks","volume":"33 1 supplement","pages":"S189 - S197"},"PeriodicalIF":1.0,"publicationDate":"2024-12-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142811161","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A. P. Dzyuba, P. A. Khorin, P. G. Serafimovich, S. N. Khonina
{"title":"Wavefront Aberrations Recognition Study Based on Multi-Channel Spatial Filter Matched with Basis Zernike Functions and Convolutional Neural Network with Xception Architecture","authors":"A. P. Dzyuba, P. A. Khorin, P. G. Serafimovich, S. N. Khonina","doi":"10.3103/S1060992X24700309","DOIUrl":"10.3103/S1060992X24700309","url":null,"abstract":"<p>The possibility of recognizing wave aberrations using a convolutional neural network with the Xception architecture is investigated based on intensity patterns at the output of a Fourier correlator with a multichannel spatial filter matched with Zernike basis functions. A dataset was calculated for training a neural network. In this dataset the intensity distribution at the correlator output was modeled for each of the first eight aberration types and their superpositions. Based on network training in 80 epochs, it was found that for the validation sample, the mean absolute error in recognizing aberrations does not exceed 0.003.</p>","PeriodicalId":721,"journal":{"name":"Optical Memory and Neural Networks","volume":"33 1 supplement","pages":"S53 - S64"},"PeriodicalIF":1.0,"publicationDate":"2024-12-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142811081","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}