{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,11,4]],"date-time":"2025-11-04T16:13:33Z","timestamp":1762272813246,"version":"build-2065373602"},"reference-count":49,"publisher":"MDPI AG","issue":"20","license":[{"start":{"date-parts":[[2021,10,11]],"date-time":"2021-10-11T00:00:00Z","timestamp":1633910400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001691","name":"Japan Society for the Promotion of Science","doi-asserted-by":"publisher","award":["JP20H02206"],"award-info":[{"award-number":["JP20H02206"]}],"id":[{"id":"10.13039\/501100001691","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>This paper describes the design and development of a cylindrical super-oscillatory lens (CSOL) for applications in the sub-terahertz frequency range, which are especially ideal for industrial inspection of films using terahertz (THz) and millimeter waves. Product inspections require high resolution (same as inspection with visible light), long working distance, and long depth of focus (DOF). However, these are difficult to achieve using conventional THz components due to diffraction limits. Here, we present a numerical approach in designing a 100 mm \u00d7 100 mm CSOL with optimum properties and performance for 0.1 THz (wavelength \u03bb = 3 mm). Simulations show that, at a focal length of 70 mm (23.3\u03bb), the focused beam by the optimized CSOL is a thin line with a width of 2.5 mm (0.84\u03bb), which is 0.79 times the diffraction limit. The DOF of 10 mm (3.3\u03bb) is longer than that of conventional lenses. The results also indicate that the generation of thin line-shaped focal beam is dominantly influenced by the outer part of the lens.<\/jats:p>","DOI":"10.3390\/s21206732","type":"journal-article","created":{"date-parts":[[2021,10,11]],"date-time":"2021-10-11T21:45:32Z","timestamp":1633988732000},"page":"6732","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["A Study of Terahertz-Wave Cylindrical Super-Oscillatory Lens for Industrial Applications"],"prefix":"10.3390","volume":"21","author":[{"given":"Ayato","family":"Iba","sequence":"first","affiliation":[{"name":"Institute of Laser Engineering, Osaka University, Osaka 565-0871, Japan"},{"name":"Asahi Kasei Corporation, Shizuoka 416-8501, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Makoto","family":"Ikeda","sequence":"additional","affiliation":[{"name":"Asahi Kasei Corporation, Shizuoka 416-8501, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Verdad C.","family":"Agulto","sequence":"additional","affiliation":[{"name":"Institute of Laser Engineering, Osaka University, Osaka 565-0871, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4944-5233","authenticated-orcid":false,"given":"Valynn Katrine","family":"Mag-usara","sequence":"additional","affiliation":[{"name":"Institute of Laser Engineering, Osaka University, Osaka 565-0871, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Makoto","family":"Nakajima","sequence":"additional","affiliation":[{"name":"Institute of Laser Engineering, Osaka University, Osaka 565-0871, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,10,11]]},"reference":[{"key":"ref_1","first-page":"317","article-title":"Millimeter-wave integrated radar systems and techniques","volume":"7","author":"Evans","year":"2018","journal-title":"Acad. 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