{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,10]],"date-time":"2026-04-10T19:27:59Z","timestamp":1775849279517,"version":"3.50.1"},"reference-count":24,"publisher":"MDPI AG","issue":"13","license":[{"start":{"date-parts":[[2021,6,29]],"date-time":"2021-06-29T00:00:00Z","timestamp":1624924800000},"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>The measurement of the Earth\u2019s Outgoing Longwave Radiation plays a key role in climate change monitoring. This measurement requires a compact wide-field-of-view camera, covering the 8\u201314 \u00b5m wavelength range, which is not commercially available. Therefore, we present a novel thermal wide-field-of-view camera optimized for space applications, featuring a field of view of 140\u00b0 to image the Earth from limb to limb, while enabling a high spatial resolution of 4.455 km at nadir. Our cost-effective design comprises three germanium lenses, of which only one has a single aspherical surface. It delivers a very good image quality, as shown by the nearly-diffraction-limited performance. Radiative transfer simulations indicate excellent performance of our camera design, enabling an estimate of the broadband Outgoing Longwave Radiation with a random relative error of 4.8%.<\/jats:p>","DOI":"10.3390\/s21134444","type":"journal-article","created":{"date-parts":[[2021,6,29]],"date-time":"2021-06-29T22:39:43Z","timestamp":1625006383000},"page":"4444","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":8,"title":["Wide-Field-of-View Longwave Camera for the Characterization of the Earth\u2019s Outgoing Longwave Radiation"],"prefix":"10.3390","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-6191-7822","authenticated-orcid":false,"given":"Luca","family":"Schifano","sequence":"first","affiliation":[{"name":"Brussels Photonics (B-PHOT), Applied Physics and Photonics Department, Vrije Universiteit Brussel, Pleinlaan 2, 1050 Brussels, Belgium"},{"name":"Royal Meteorological Institute of Belgium, Avenue Circulaire 3, 1180 Brussels, Belgium"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Lien","family":"Smeesters","sequence":"additional","affiliation":[{"name":"Brussels Photonics (B-PHOT), Applied Physics and Photonics Department, Vrije Universiteit Brussel, Pleinlaan 2, 1050 Brussels, Belgium"},{"name":"Flanders Make, Pleinlaan 2, 1050 Brussels, Belgium"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0822-233X","authenticated-orcid":false,"given":"Francis","family":"Berghmans","sequence":"additional","affiliation":[{"name":"Brussels Photonics (B-PHOT), Applied Physics and Photonics Department, Vrije Universiteit Brussel, Pleinlaan 2, 1050 Brussels, Belgium"},{"name":"Flanders Make, Pleinlaan 2, 1050 Brussels, Belgium"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Steven","family":"Dewitte","sequence":"additional","affiliation":[{"name":"Royal Meteorological Institute of Belgium, Avenue Circulaire 3, 1180 Brussels, Belgium"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,6,29]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Dewitte, S., and Clerbaux, N. 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