{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T04:20:04Z","timestamp":1760242804895,"version":"build-2065373602"},"reference-count":34,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2016,11,25]],"date-time":"2016-11-25T00:00:00Z","timestamp":1480032000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Ministry of Science and Technology","award":["MOST 104-2622-E-009-014-CC2","NSC 102-2221-E-009-155-MY3","MOST 105-2221-E-008-111"],"award-info":[{"award-number":["MOST 104-2622-E-009-014-CC2","NSC 102-2221-E-009-155-MY3","MOST 105-2221-E-008-111"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>For many practical applications of image sensors, how to extend the depth-of-field (DoF) is an important research topic; if successfully implemented, it could be beneficial in various applications, from photography to biometrics. In this work, we want to examine the feasibility and practicability of a well-known \u201cextended DoF\u201d (EDoF) technique, or \u201cwavefront coding,\u201d by building real-time long-range iris recognition and performing large-scale iris recognition. The key to the success of long-range iris recognition includes long DoF and image quality invariance toward various object distance, which is strict and harsh enough to test the practicality and feasibility of EDoF-empowered image sensors. Besides image sensor modification, we also explored the possibility of varying enrollment\/testing pairs. With 512 iris images from 32 Asian people as the database, 400-mm focal length and F\/6.3 optics over 3 m working distance, our results prove that a sophisticated coding design scheme plus homogeneous enrollment\/testing setups can effectively overcome the blurring caused by phase modulation and omit Wiener-based restoration. In our experiments, which are based on 3328 iris images in total, the EDoF factor can achieve a result 3.71 times better than the original system without a loss of recognition accuracy.<\/jats:p>","DOI":"10.3390\/s16121994","type":"journal-article","created":{"date-parts":[[2016,11,25]],"date-time":"2016-11-25T08:18:15Z","timestamp":1480061895000},"page":"1994","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["Test of the Practicality and Feasibility of EDoF-Empowered Image Sensors for Long-Range Biometrics"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-2813-2286","authenticated-orcid":false,"given":"Sheng-Hsun","family":"Hsieh","sequence":"first","affiliation":[{"name":"Department of Photonics, National Chiao Tung University, 1001 University Road, Hsinchu 30010, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0475-3689","authenticated-orcid":false,"given":"Yung-Hui","family":"Li","sequence":"additional","affiliation":[{"name":"Department of Computer Science &amp; Information Engineering, National Central University, No. 300 Zhongda Road, Zhongli District, Taoyuan 32001, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Chung-Hao","family":"Tien","sequence":"additional","affiliation":[{"name":"Department of Photonics, National Chiao Tung University, 1001 University Road, Hsinchu 30010, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2016,11,25]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"4","DOI":"10.1109\/TCSVT.2003.818349","article-title":"An introduction to biometric recognition","volume":"14","author":"AJain","year":"2004","journal-title":"IEEE Trans. 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