Refraction of the Eye Using the Properties of Laser Speckle. Diffractive Multi-Color Phoroptor Based on Laser Speckle.
Abstract
Relative motion between an observer and a scattering screen illuminated with coherent light can cause the resulting speckle pattern to scintillate. The relative direction of motion can therefore be used to measure the refractive error of the eye. If the speckles do not move but seem to boil in space, the object is determined to be conjugate to the retina. The primary objective of the research is to demonstrate the feasibility of a lensless, multi- color phoroptor system that uses laser speckle. The instrument must be easy to operate and the data should require little or no further analysis. The vision test should require the patient to provide only simple answers to questions regarding speckle motion. We have identified innovative designs that employ a minimum of optical elements without sacrificing performance or light efficiency while maintaining mechanical stability. During Phase I, we have generated detailed optical designs and have fabricated a functional breadboard multi-color laser optometer. We investigated innovative uses of conventional and diffractive optics in new designs for future-generation systems that utilize red, green and blue visible laser diodes. The manufacturability of the system components was studied. We have developed a SBIR Phase II program that we believe will lead to versatile and commercially viable laser-based optometers. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Aug 15, 1991
- Accession Number
- ADB158962
Entities
People
- Dean Faklis
- John P. Bowen
- Lennart A. Saaf