FIELD: medicine; ophthalmology.
SUBSTANCE: digital photorecording of lens surface through optical filter propagating wavelength 530-540 nm is performed. Digital photo is analysed for average pixel brightness corresponding to meniscus area of maximum lachrymal recovery along contact lens periphery, average pixel brightness corresponding to contact lens edge, pixel brightness corresponding to analysed point of contact lens. For this point lachrymal gap thickness is calculated by formula: where H is lachrymal gap thickness in analysed point under contact lens, B is pixel brightness corresponding to this point of digital photo, Bm is average pixel brightness corresponding to meniscus area of maximum lachrymal recovery along contact lens periphery, Br is average pixel brightness corresponding to contact lens edge, l is thickness of contact lens edge.
EFFECT: method enables to control accuracy of hard contact lens adjustment and to improve fit quality.
3 dwg, 2 ex
Authors
Dates
2009-03-10—Published
2008-04-14—Filed