Measuring refractive error in the human eye using a Shack-Hartmann-based autorefractor

Persistent Link:
http://hdl.handle.net/10150/298729
Title:
Measuring refractive error in the human eye using a Shack-Hartmann-based autorefractor
Author:
Beverage, Jacob Lee
Issue Date:
2003
Publisher:
The University of Arizona.
Rights:
Copyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.
Abstract:
The oldest and most prevalent optical system in the world is the human eye. Variations in the anatomical structure of the eye can cause errors in its optical performance, which in turn lead to errors in the overall performance of the visual system. Fortunately, these refractive errors can be measured and then corrected externally with spectacles, contact lenses, or refractive surgery. This dissertation describes the design, fabrication, and testing of a new autorefractor that can be used to objectively measure human refractive error. The new autorefractor is based on Shack-Hartmann wavefront sensing techniques and uses a novel, Fourier transform-based algorithm to estimate refractive error. The Fourier-based data analysis models the wavefront aberration as a combination of defocus and astigmatism only, expresses the simplified wavefront in terms of measurable quantities in Fourier-space, and relates the coefficients describing the wavefront to the patient's refraction. The Shack-Hartmann-based autorefractor (SHAR) is designed to be inexpensive and compact to facilitate its transition to a commercial device. It represents a significant improvement in automated clinical refraction because it can make accurate measurements of a wide range of refractive errors without relying on moving parts or the intensity of light reflected off the retina. To evaluate its performance, the SHAR was compared to the gold-standard among current commercially available autorefractors in a study of human refractive errors. The results from this limited study population suggested that the SHAR has the potential to perform at least as well as the commercial standard autorefractor.
Type:
text; Dissertation-Reproduction (electronic)
Keywords:
Health Sciences, Ophthalmology.
Degree Name:
Ph.D.
Degree Level:
doctoral
Degree Program:
Graduate College; Optical Sciences
Degree Grantor:
University of Arizona
Advisor:
Schwiegerling, James T.

Full metadata record

DC FieldValue Language
dc.language.isoen_USen_US
dc.titleMeasuring refractive error in the human eye using a Shack-Hartmann-based autorefractoren_US
dc.creatorBeverage, Jacob Leeen_US
dc.contributor.authorBeverage, Jacob Leeen_US
dc.date.issued2003en_US
dc.publisherThe University of Arizona.en_US
dc.rightsCopyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.en_US
dc.description.abstractThe oldest and most prevalent optical system in the world is the human eye. Variations in the anatomical structure of the eye can cause errors in its optical performance, which in turn lead to errors in the overall performance of the visual system. Fortunately, these refractive errors can be measured and then corrected externally with spectacles, contact lenses, or refractive surgery. This dissertation describes the design, fabrication, and testing of a new autorefractor that can be used to objectively measure human refractive error. The new autorefractor is based on Shack-Hartmann wavefront sensing techniques and uses a novel, Fourier transform-based algorithm to estimate refractive error. The Fourier-based data analysis models the wavefront aberration as a combination of defocus and astigmatism only, expresses the simplified wavefront in terms of measurable quantities in Fourier-space, and relates the coefficients describing the wavefront to the patient's refraction. The Shack-Hartmann-based autorefractor (SHAR) is designed to be inexpensive and compact to facilitate its transition to a commercial device. It represents a significant improvement in automated clinical refraction because it can make accurate measurements of a wide range of refractive errors without relying on moving parts or the intensity of light reflected off the retina. To evaluate its performance, the SHAR was compared to the gold-standard among current commercially available autorefractors in a study of human refractive errors. The results from this limited study population suggested that the SHAR has the potential to perform at least as well as the commercial standard autorefractor.en_US
dc.typetexten_US
dc.typeDissertation-Reproduction (electronic)en_US
dc.subjectHealth Sciences, Ophthalmology.en_US
thesis.degree.namePh.D.en_US
thesis.degree.leveldoctoralen_US
thesis.degree.disciplineGraduate Collegeen_US
thesis.degree.disciplineOptical Sciencesen_US
thesis.degree.grantorUniversity of Arizonaen_US
dc.contributor.advisorSchwiegerling, James T.en_US
dc.identifier.proquest3108885en_US
dc.identifier.bibrecord.b44824853en_US
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