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(Reference retrieved automatically from SciELO through information on FAPESP grant and its corresponding number as mentioned in the publication by the authors.)

Preliminary results of a high-resolution refractometer using the Hartmann-Shack wave-front sensor: part I

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Luis Alberto Carvalho ; Antonio Carlos Romao ; Marcos Stefani ; Luiz Antonio Carvalho ; Jarbas Caiado de Castro ; Fátima Yasuoka ; Francisco Scannavino Júnior ; Juselino dos Santos ; Paulo Schor ; Wallace Chamon
Total Authors: 10
Document type: Journal article
Source: Arquivos Brasileiros de Oftalmologia; v. 66, n. 3, p. 261-268, Jun. 2003.

In this project we are developing an instrument for measuring the wave-front aberrations of the human eye using the Hartmann-Shack sensor. A laser source is directed towards the eye and its diffuse reflection at the retina generates an approximately spherical wave-front inside the eye. This wave-front travels through the different components of the eye (vitreous humor, lens, aqueous humor, and cornea) and then leaves the eye carrying information about the aberrations caused by these components. Outside the eye there is an optical system composed of an array of microlenses and a CCD camera. The wave-front hits the microlens array and forms a pattern of spots at the CCD plane. Image processing algorithms detect the center of mass of each spot and this information is used to calculate the exact wave-front surface using least squares approximation by Zernike polynomials. We describe here the details of the first phase of this project, i. e., the construction of the first generation of prototype instruments and preliminary results for an artificial eye calibrated with different ametropias, i. e., myopia, hyperopia and astigmatism. (AU)

FAPESP's process: 00/06810-4 - Development of equipment for the determination of ocular aberrations using wave-front measurements by way of the Harmann-Shack Technique
Grantee:Jarbas Caiado de Castro Neto
Support type: Research Grants - Innovative Research in Small Business - PIPE