{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,28]],"date-time":"2026-01-28T10:12:13Z","timestamp":1769595133406,"version":"3.49.0"},"reference-count":44,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2016,3,25]],"date-time":"2016-03-25T00:00:00Z","timestamp":1458864000000},"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>A terahertz (THz) imaging system based on narrow band microbolometer sensors (NBMS) and a novel diffractive lens was developed for spectroscopic microscopy applications. The frequency response characteristics of the THz antenna-coupled NBMS were determined employing Fourier transform spectroscopy. The NBMS was found to be a very sensitive frequency selective sensor which was used to develop a compact all-electronic system for multispectral THz measurements. This system was successfully applied for principal components analysis of optically opaque packed samples. A thin diffractive lens with a numerical aperture of 0.62 was proposed for the reduction of system dimensions. The THz imaging system enhanced with novel optics was used to image for the first time non-neoplastic and neoplastic human colon tissues with close to wavelength-limited spatial resolution at 584 GHz frequency. The results demonstrated the new potential of compact RT THz imaging systems in the fields of spectroscopic analysis of materials and medical diagnostics.<\/jats:p>","DOI":"10.3390\/s16040432","type":"journal-article","created":{"date-parts":[[2016,3,29]],"date-time":"2016-03-29T16:00:28Z","timestamp":1459267228000},"page":"432","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":75,"title":["Spectroscopic Terahertz Imaging at Room Temperature Employing Microbolometer Terahertz Sensors and Its Application to the Study of Carcinoma Tissues"],"prefix":"10.3390","volume":"16","author":[{"given":"Irmantas","family":"Ka\u0161alynas","sequence":"first","affiliation":[{"name":"Department of Optoelectronics, Center for Physical Sciences and Technology, Savanoriu Ave. 231, Vilnius 02300, Lithuania"}]},{"given":"Rimvydas","family":"Venckevi\u010dius","sequence":"additional","affiliation":[{"name":"Department of Optoelectronics, Center for Physical Sciences and Technology, Savanoriu Ave. 231, Vilnius 02300, Lithuania"}]},{"given":"Linas","family":"Minkevi\u010dius","sequence":"additional","affiliation":[{"name":"Department of Optoelectronics, Center for Physical Sciences and Technology, Savanoriu Ave. 231, Vilnius 02300, Lithuania"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7369-1103","authenticated-orcid":false,"given":"Aleksander","family":"Se\u0161ek","sequence":"additional","affiliation":[{"name":"Faculty of Electrical Engineering, University of Ljubljana, Trzaska 25, Ljubljana 1000, Slovenia"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8920-1383","authenticated-orcid":false,"given":"Faustino","family":"Wahaia","sequence":"additional","affiliation":[{"name":"Instituto de Investigacao e Inovacao em Saudeand, Instituto de Engenharia Biomedica, University of Porto, Rua do Campo Alegre, 823, Porto 4150-180, Portugal"}]},{"given":"Vincas","family":"Tamo\u0161i\u016bnas","sequence":"additional","affiliation":[{"name":"Department of Optoelectronics, Center for Physical Sciences and Technology, Savanoriu Ave. 231, Vilnius 02300, Lithuania"}]},{"given":"Bogdan","family":"Voisiat","sequence":"additional","affiliation":[{"name":"Department of Optoelectronics, Center for Physical Sciences and Technology, Savanoriu Ave. 231, Vilnius 02300, Lithuania"}]},{"given":"Dalius","family":"Seliuta","sequence":"additional","affiliation":[{"name":"Department of Optoelectronics, Center for Physical Sciences and Technology, Savanoriu Ave. 231, Vilnius 02300, Lithuania"}]},{"given":"Gintaras","family":"Valu\u0161is","sequence":"additional","affiliation":[{"name":"Department of Optoelectronics, Center for Physical Sciences and Technology, Savanoriu Ave. 231, Vilnius 02300, Lithuania"}]},{"given":"Andrej","family":"\u0160vigelj","sequence":"additional","affiliation":[{"name":"Faculty of Electrical Engineering, University of Ljubljana, Trzaska 25, Ljubljana 1000, Slovenia"}]},{"given":"Janez","family":"Trontelj","sequence":"additional","affiliation":[{"name":"Faculty of Electrical Engineering, University of Ljubljana, Trzaska 25, Ljubljana 1000, Slovenia"}]}],"member":"1968","published-online":{"date-parts":[[2016,3,25]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1325","DOI":"10.1088\/0034-4885\/70\/8\/R02","article-title":"Imaging with Terahertz Radiation","volume":"70","author":"Chan","year":"2007","journal-title":"Reports Prog. 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