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<article xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:ali="http://www.niso.org/schemas/ali/1.0/" article-type="research-article" dtd-version="1.2" xml:lang="en"><front><journal-meta><journal-id journal-id-type="publisher-id">Discrete and Continuous Models and Applied Computational Science</journal-id><journal-title-group><journal-title xml:lang="en">Discrete and Continuous Models and Applied Computational Science</journal-title><trans-title-group xml:lang="ru"><trans-title>Discrete and Continuous Models and Applied Computational Science</trans-title></trans-title-group></journal-title-group><issn publication-format="print">2658-4670</issn><issn publication-format="electronic">2658-7149</issn><publisher><publisher-name xml:lang="en">Peoples' Friendship University of Russia named after Patrice Lumumba (RUDN University)</publisher-name></publisher></journal-meta><article-meta><article-id pub-id-type="publisher-id">33016</article-id><article-id pub-id-type="doi">10.22363/2658-4670-2022-30-4-357-363</article-id><article-categories><subj-group subj-group-type="toc-heading" xml:lang="en"><subject>Articles</subject></subj-group><subj-group subj-group-type="toc-heading" xml:lang="ru"><subject>Статьи</subject></subj-group><subj-group subj-group-type="article-type"><subject>Research Article</subject></subj-group></article-categories><title-group><article-title xml:lang="en">Profile thickness synthesis of thin-film waveguide Luneburg lens</article-title><trans-title-group xml:lang="ru"><trans-title>Синтез толщины профиля тонкоплёночной волноводной линзы Люнеберга</trans-title></trans-title-group></title-group><contrib-group><contrib contrib-type="author"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0002-3645-1060</contrib-id><name-alternatives><name xml:lang="en"><surname>Lovetskiy</surname><given-names>Konstantin P.</given-names></name><name xml:lang="ru"><surname>Ловецкий</surname><given-names>К. П.</given-names></name></name-alternatives><bio xml:lang="en"><p>Candidate of Physical and Mathematical Sciences, Associate Professor of Department of Applied Probability and Informatics</p></bio><email>lovetskiy-kp@rudn.ru</email><xref ref-type="aff" rid="aff1"/></contrib><contrib contrib-type="author"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0002-0280-485X</contrib-id><name-alternatives><name xml:lang="en"><surname>Sevastianov</surname><given-names>Anton L.</given-names></name><name xml:lang="ru"><surname>Севастьянов</surname><given-names>А. Л.</given-names></name></name-alternatives><bio xml:lang="en"><p>Candidate of Physical and Mathematical Sciences, Deputy Head of Department of Education digitalization</p></bio><email>alsevastyanov@gmail.com</email><xref ref-type="aff" rid="aff2"/></contrib><contrib contrib-type="author"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0002-5721-4558</contrib-id><name-alternatives><name xml:lang="en"><surname>Zorin</surname><given-names>Alexander V.</given-names></name><name xml:lang="ru"><surname>Зорин</surname><given-names>А. В.</given-names></name></name-alternatives><bio xml:lang="en"><p>Doctor of Physical and Mathematical Sciences, Assistant Professor of Department of Applied Probability and Informatics</p></bio><email>zorin-av@rudn.ru</email><xref ref-type="aff" rid="aff1"/></contrib></contrib-group><aff-alternatives id="aff1"><aff><institution xml:lang="en">Peoples’ Friendship University of Russia (RUDN University)</institution></aff><aff><institution xml:lang="ru">Российский университет дружбы народов</institution></aff></aff-alternatives><aff-alternatives id="aff2"><aff><institution xml:lang="en">Higher School of Economics (HSE University)</institution></aff><aff><institution xml:lang="ru">Высшая школа экономики</institution></aff></aff-alternatives><pub-date date-type="pub" iso-8601-date="2022-12-26" publication-format="electronic"><day>26</day><month>12</month><year>2022</year></pub-date><volume>30</volume><issue>4</issue><issue-title xml:lang="en">VOL 30, NO4 (2022)</issue-title><issue-title xml:lang="ru">ТОМ 30, №4 (2022)</issue-title><fpage>357</fpage><lpage>363</lpage><history><date date-type="received" iso-8601-date="2022-12-26"><day>26</day><month>12</month><year>2022</year></date></history><permissions><copyright-statement xml:lang="en">Copyright ©; 2022, Lovetskiy K.P., Sevastianov A.L., Zorin A.V.</copyright-statement><copyright-statement xml:lang="ru">Copyright ©; 2022, Ловецкий К.П., Севастьянов А.Л., Зорин А.В.</copyright-statement><copyright-year>2022</copyright-year><copyright-holder xml:lang="en">Lovetskiy K.P., Sevastianov A.L., Zorin A.V.</copyright-holder><copyright-holder xml:lang="ru">Ловецкий К.П., Севастьянов А.Л., Зорин А.В.</copyright-holder><ali:free_to_read xmlns:ali="http://www.niso.org/schemas/ali/1.0/"/><license><ali:license_ref xmlns:ali="http://www.niso.org/schemas/ali/1.0/">https://creativecommons.org/licenses/by-nc/4.0</ali:license_ref></license></permissions><self-uri xlink:href="https://journals.rudn.ru/miph/article/view/33016">https://journals.rudn.ru/miph/article/view/33016</self-uri><abstract xml:lang="en"><p style="text-align: justify;">In the work the link between the focusing inhomogeneity of the effective refractive index of waveguide Luneburg lens and the irregularity of the waveguide layer thickness generating this inhomogeneity is demonstrated. For the dispersion relation of irregular thin-film waveguide in the model of adiabatic waveguide modes the problem of mathematical synthesis and computer-aided design of the waveguide layer thickness profile for the Luneburg thin-film generalized waveguide lens with a given focal length is being solved. The calculations are carried out in normalized (in a special way) coordinates to adapt the used relations to computer calculations. The obtained solution is compared with the same solution within the cross-section’s method. The performance of the algorithm implemented in Delphi, was demonstrated by plotting the dispersion curves and plotting a family of dispersion curves, demonstrating a critical convergence. As an additional result, the thickness profiles of additional (irregular in thickness) waveguide layer, forming a thin film generalized waveguide Luneburg lens were synthesized. This result generalizes Southwell’s results.</p></abstract><trans-abstract xml:lang="ru"><p style="text-align: justify;">В работе показана связь между фокусирующей неоднородностью эффективного показателя преломления волноводной линзы Люнеберга и неравномерностью толщины волноводного слоя, порождающей эту неоднородность. Для закона дисперсии нерегулярного тонкоплёночного волновода в модели адиабатических мод волновода решается задача математического синтеза и компьютерного проектирования профиля толщины волноводного слоя для тонкоплёночной обобщённой волноводной линзы Люнеберга с заданным фокусным расстоянием. Расчёты ведутся в нормированных специальным образом координатах для адаптации используемых соотношений к компьютерным расчётам. Полученное решение сравнивается с таким же решением в рамках метода сечений. Работоспособность алгоритма, реализованного в Delphi, была продемонстрирована путём построения дисперсионных кривых и семейства дисперсионных кривых, показывающих критическую сходимость. В качестве дополнительного результата были синтезированы профили толщины дополнительного нерегулярного по толщине волноводного слоя, образующего тонкоплёночную обобщённую волноводную линзу Люнеберга. Этот результат обобщает результаты Саутвелла.</p></trans-abstract><kwd-group xml:lang="en"><kwd>Luneburg waveguide lens</kwd><kwd>effective refractive index inhomogeneity</kwd><kwd>section method</kwd><kwd>waveguide adiabatic mode model</kwd></kwd-group><kwd-group xml:lang="ru"><kwd>волноводная линза Люнеберга</kwd><kwd>неоднородность эффективного показателя преломления</kwd><kwd>метод сечений</kwd><kwd>модель адиабатических мод волновода</kwd></kwd-group><funding-group/></article-meta></front><body></body><back><ref-list><ref id="B1"><label>1.</label><mixed-citation>A. L. 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