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Published on: July 6, 2019
Assessing the phase retardation in corneal tissues using a femtosecond laser
William Calhoun1, Richard Weiblinger, Alexander Beylin
1Optical Therapeutics and Medical Nanophotonics Laboratory, Office of Science and Engineering Laboratories U.S. Food and Drug Administration, Silver Spring, Maryland 20993, USA.
Abstract:
We developed and validated a versatile test method for precise quantification of phase retardation in corneal tissues using a femtosecond laser. It is based on an experimental system for direct measurement of corneal phase rotation due to corneal birefringence effects using a dual-polarizer, computer-controlled, femtosecond laser design. It also includes a comprehensive analytical model using Jones matrices. The test method presented is used for quantification of phase retardation in corneal tissues by employing the experimental data obtained from corneal phase rotation measurements and using analytical model assessments. The experimental and theoretical results obtained, and thus, the system's high accuracy and repeatability potential for assessing the corneal phase retardation are validated using control phase retardation evaluation.
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