{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,12]],"date-time":"2026-06-12T22:53:35Z","timestamp":1781304815734,"version":"3.54.1"},"reference-count":18,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2020,4,30]],"date-time":"2020-04-30T00:00:00Z","timestamp":1588204800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100005632","name":"Narodowe Centrum Bada\u0144 i Rozwoju","doi-asserted-by":"publisher","award":["DOB-1-6\/1\/PS\/2014"],"award-info":[{"award-number":["DOB-1-6\/1\/PS\/2014"]}],"id":[{"id":"10.13039\/501100005632","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>In this paper, we present a novel configuration of an optical angle-of-incidence (AOI) sensor based on the application of a freeform mirror. The main challenge in designing this mirror was to provide a strictly linear transformation between AOI and the spatial position of the spot created on the linear detector array. Another two goals of this paper were to minimize stray light issues (improve the dynamic range) and create an intermediate focus and lateral shift in the detector position with respect to the plane of incidence. From an optical point of view, the designed mirror can thus be understood as the composition of three components: a high-numerical-aperture (NA) fully achromatic f-theta lens in one cross-section and a perfectly focusing lens, combined with a deviating prism in the second (orthogonal) cross-section. In comparison to the standard \u201cshade\u201d methods, the proposed approach allows a constant angular resolution to be maintained over the entire field of view. The mirror was designed on the basis of fundamental geometrical rules by numerically solving differential problems using an innovative scheme based on the minimization of the specific merit function. The proposed method was practically applied to design a freeform mirror for a 90\u00b0\/120\u00b0 field-of-view sensor, showing a satisfactory performance.<\/jats:p>","DOI":"10.3390\/s20092569","type":"journal-article","created":{"date-parts":[[2020,5,4]],"date-time":"2020-05-04T14:00:43Z","timestamp":1588600843000},"page":"2569","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":12,"title":["Freeform Mirror Design for Novel Laser Warning Receivers and Laser Angle of Incidence Sensors"],"prefix":"10.3390","volume":"20","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-2771-4471","authenticated-orcid":false,"given":"Jacek","family":"Wojtanowski","sequence":"first","affiliation":[{"name":"Institute of Optoelectronics, Military University of Technology, 00-908 Warsaw, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Marcin","family":"Jakubaszek","sequence":"additional","affiliation":[{"name":"Institute of Optoelectronics, Military University of Technology, 00-908 Warsaw, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9058-9178","authenticated-orcid":false,"given":"Marek","family":"Zygmunt","sequence":"additional","affiliation":[{"name":"Institute of Optoelectronics, Military University of Technology, 00-908 Warsaw, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2020,4,30]]},"reference":[{"key":"ref_1","unstructured":"Nerri, F. 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Opt."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"20974","DOI":"10.1364\/OE.21.020974","article-title":"A mathematical model of the single freeform surface design for collimated beam shaping","volume":"21","author":"Wu","year":"2013","journal-title":"Opt. Expr."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"439","DOI":"10.1109\/34.3909","article-title":"A method for enforcing integrability in shape from shading algorithms","volume":"10","author":"Frankot","year":"1988","journal-title":"IEEE Trans. Pattern Anal. Mach. Intell."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"1019","DOI":"10.1080\/09500340.2017.1422563","article-title":"Efficient numerical method of freeform lens design for arbitrary irradiance shaping","volume":"65","author":"Wojtanowski","year":"2018","journal-title":"J. Mod. Opt."},{"key":"ref_17","unstructured":"Zemax (2020, March 10). Everything You Need to Design Optical Systems. 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