{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,28]],"date-time":"2026-02-28T10:47:22Z","timestamp":1772275642827,"version":"3.50.1"},"reference-count":27,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2026,2,26]],"date-time":"2026-02-26T00:00:00Z","timestamp":1772064000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Guangzhou National Laboratory","award":["GZNL2024A01029"],"award-info":[{"award-number":["GZNL2024A01029"]}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"crossref","award":["62505056"],"award-info":[{"award-number":["62505056"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"crossref"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["J. Imaging"],"abstract":"<jats:p>Lensless on-chip microscopy enables high-throughput, wide-FOV imaging; however, the Bayer color filter array (CFA) in standard color sensors spatially multiplexes spectral channels, introducing sub-sampling and spectral crosstalk that degrade phase retrieval. We propose a Wirtinger Poly-Gradient Solver (WPGS) for quantitative phase reconstruction with Bayer-filtered color sensors under sequential Red\u2013Green\u2013Blue Light-Emitting Diode (RGB-LED) illumination. The method combines Transport of Intensity Equation (TIE)-based initialization with polychromatic Wirtinger optimization to suppress CFA-induced artifacts and enable pixel super-resolution (PSR). Experiments resolve a 2.76\u00a0\u03bcm linewidth using a 1.85\u00a0\u03bcm pixel-pitch sensor, exceeding the nominal Nyquist limit imposed by pixel sampling. We further demonstrate label-free imaging of HeLa cells and unstained tissue sections, supporting high-throughput digital pathology and offering potential for longitudinal biological observation.<\/jats:p>","DOI":"10.3390\/jimaging12030101","type":"journal-article","created":{"date-parts":[[2026,2,26]],"date-time":"2026-02-26T14:51:29Z","timestamp":1772117489000},"page":"101","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Lensless Quantitative Phase Imaging with Bayer-Filtered Color Sensors Under Sequential RGB-LED Illumination"],"prefix":"10.3390","volume":"12","author":[{"given":"Jiajia","family":"Wu","sequence":"first","affiliation":[{"name":"School of Physics, TEDA Institute of Applied Physics, Nankai University, Tianjin 300071, China"},{"name":"Guangzhou National Laboratory, Guangzhou International BioIsland, Guangzhou 510005, China"}]},{"given":"Yining","family":"Li","sequence":"additional","affiliation":[{"name":"Guangzhou National Laboratory, Guangzhou International BioIsland, Guangzhou 510005, China"}]},{"given":"Yuheng","family":"Luo","sequence":"additional","affiliation":[{"name":"Guangzhou National Laboratory, Guangzhou International BioIsland, Guangzhou 510005, China"}]},{"given":"Leiting","family":"Pan","sequence":"additional","affiliation":[{"name":"School of Physics, TEDA Institute of Applied Physics, Nankai University, Tianjin 300071, China"},{"name":"Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan 030006, China"}]},{"given":"Pengming","family":"Song","sequence":"additional","affiliation":[{"name":"Guangzhou National Laboratory, Guangzhou International BioIsland, Guangzhou 510005, China"}]},{"given":"Qiang","family":"Xu","sequence":"additional","affiliation":[{"name":"Guangzhou National Laboratory, Guangzhou International BioIsland, Guangzhou 510005, China"}]}],"member":"1968","published-online":{"date-parts":[[2026,2,26]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"E151","DOI":"10.1038\/35019639","article-title":"Lessons from the history of light microscopy","volume":"2","author":"Amos","year":"2000","journal-title":"Nat. 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