{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,15]],"date-time":"2026-01-15T10:06:53Z","timestamp":1768471613258,"version":"3.49.0"},"reference-count":35,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2020,5,1]],"date-time":"2020-05-01T00:00:00Z","timestamp":1588291200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>This work presents a formation method of mechanically-induced long-period fiber gratings using laminated plates. The mechanically-induced long-period fiber grating is temporarily inscribed by compressing the optical fiber between a flat plate and the proposed laminated plate. In turn, the new laminated plate consists of a parallel assembling of single-edged utility blades. We present the experimental characterization of mechanically-induced long-period fiber gratings while employing three laminated plates with a period of 480 \u00b1 20 \u00b5m and low duty cycles. These mechanically-induced long-period fiber gratings display a leading rejection band (&gt;15 dB) with a couple of shallow rejection bands (&lt;2 dB) in the range of 1100\u20131700 nm. This spectral behavior is due to the new mechanical fabrication process that is based on laminated plates that we have proposed, which consists of piling multiple blades with trapezoidal edges that are polished with different levels to obtain different duty-cycles. With the proposed method, we can obtain values of duty-cycles around 10%, much lower than those obtained using traditional methods. Additionally, with this new method, the required mechanical pressure to form the grating is remarkably reduced, which minimizes the probability of the optical fiber failure in the mechanically-induced long-period fiber gratings (MI-LPFGs). Moreover, the proposed mechanically-induced long-period fiber gratings with a single rejection band open the feasibility to implement coarse wavelength division multiplexing systems that are based on long-period fiber gratings.<\/jats:p>","DOI":"10.3390\/s20092582","type":"journal-article","created":{"date-parts":[[2020,5,4]],"date-time":"2020-05-04T14:00:43Z","timestamp":1588600843000},"page":"2582","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":19,"title":["Mechanically-Induced Long-Period Fiber Gratings Using Laminated Plates"],"prefix":"10.3390","volume":"20","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-6701-2677","authenticated-orcid":false,"given":"Ismael","family":"Torres-G\u00f3mez","sequence":"first","affiliation":[{"name":"Centro de Investigaciones en \u00d3ptica AC, Loma del Bosque 115, Le\u00f3n Gto. 37150, Mexico"}]},{"given":"Daniel E.","family":"Ceballos-Herrera","sequence":"additional","affiliation":[{"name":"Instituto de Ingenier\u00eda, Universidad Nacional Aut\u00f3noma de M\u00e9xico (UNAM), Cd. Universitaria, Alcald\u00eda Coyoac\u00e1n 04510, Mexico"}]},{"given":"Karla M.","family":"Salas-Alcantara","sequence":"additional","affiliation":[{"name":"Centro de Investigaciones en \u00d3ptica AC, Loma del Bosque 115, Le\u00f3n Gto. 37150, Mexico"}]}],"member":"1968","published-online":{"date-parts":[[2020,5,1]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"58","DOI":"10.1109\/50.476137","article-title":"Long-period fiber gratings as band-rejection filters","volume":"14","author":"Vengsarkar","year":"1996","journal-title":"J. Lightware Technol."},{"key":"ref_2","unstructured":"Chiang, K.S., and Liu, Q. (2006, January 23\u201327). Long-period grating devices for application in optical communications. 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