{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,22]],"date-time":"2026-05-22T13:05:59Z","timestamp":1779455159026,"version":"3.53.1"},"reference-count":42,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2026,5,22]],"date-time":"2026-05-22T00:00:00Z","timestamp":1779408000000},"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>Accurate intraocular pressure (IOP) assessment is essential for glaucoma diagnosis and follow-up. Conventional contact tonometry (e.g., Goldmann and rebound devices) remains widely used, but its accuracy is affected by operator dependence, alignment errors, and patient discomfort. We present a non-contact IOP estimation framework based on corneal stress birefringence and full-field fringe inversion. Ex vivo porcine corneas were imaged under controlled pressure loading from 15 to 20 mmHg, and a coupled stress-optic\/shell mechanics model was used to generate pressure-indexed synthetic fringe fields for inverse fitting. In the 15\u201318 mmHg range, more than 75% of the estimates were within plus or minus 1 mmHg of the reference pressure; performance declined at 19\u201320 mmHg, consistent with a stronger nonlinear biomechanical response and reduced fringe separability. Defect experiments further showed that local stiffness loss caused both near-defect distortion and far-field stress redistribution, supporting the need for full-field rather than point-wise analysis. These results indicate that stress-birefringence imaging is a promising route toward non-contact, region-sensitive IOP assessment.<\/jats:p>","DOI":"10.3390\/s26113289","type":"journal-article","created":{"date-parts":[[2026,5,22]],"date-time":"2026-05-22T12:14:52Z","timestamp":1779452092000},"page":"3289","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Non-Contact IOP Estimation Based on Corneal Stress Birefringence: Experimental and Computational Validation"],"prefix":"10.3390","volume":"26","author":[{"given":"Haoyuan","family":"Li","sequence":"first","affiliation":[{"name":"School of Science, Hebei University of Technology, Tianjin 300401, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yinda","family":"Li","sequence":"additional","affiliation":[{"name":"School of Science, Hebei University of Technology, Tianjin 300401, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zhenhua","family":"Guo","sequence":"additional","affiliation":[{"name":"School of Science, Hebei University of Technology, Tianjin 300401, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yong","family":"Zhang","sequence":"additional","affiliation":[{"name":"School of Science, Hebei University of Technology, Tianjin 300401, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,5,22]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"159","DOI":"10.1159\/000272028","article-title":"The in Vitro Study of Pressure Change Effect on Corneal Birefringence","volume":"43","author":"Xiao","year":"2010","journal-title":"Ophthalmic Res."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"169","DOI":"10.1159\/000320600","article-title":"A New Noncontact Tonometer Using Corneal Photoelasticity: Porcine Eye Study","volume":"45","author":"Hwang","year":"2011","journal-title":"Ophthalmic Res."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"166529","DOI":"10.1016\/j.ijleo.2021.166529","article-title":"Implications of the Structure-Property Relationship on the Optomechanical Characterization of the Cornea: A Review","volume":"232","author":"Gururani","year":"2021","journal-title":"Optik"},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"132","DOI":"10.1007\/s10792-024-03057-1","article-title":"Corneal biomechanics and diagnostics: A review","volume":"44","author":"Komninou","year":"2024","journal-title":"Int. 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