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Applied Optics

Applied Optics

APPLICATIONS-CENTERED RESEARCH IN OPTICS

  • Vol. 40, Iss. 31 — Nov. 1, 2001
  • pp: 5778–5786

Object surface for applying a modified Hartmann test to measure corneal topography

Yobani Mejía-Barbosa and Daniel Malacara-Hernández  »View Author Affiliations


Applied Optics, Vol. 40, Issue 31, pp. 5778-5786 (2001)
http://dx.doi.org/10.1364/AO.40.005778


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Abstract

A modified Hartmann test is proposed for measuring corneal topography. The plane screen with holes used in the typical Hartmann test is replaced with a curved object surface. This object surface yields a plane image for a spherical mirror surface. We show that the object surface is an oval of revolution that can be modeled by an ellipsoid. The plane image will be formed by a square array of circular spots, all with the same diameter. To obtain the square array in the image, we calculated the spatial distribution of the spots on the object surface.

© 2001 Optical Society of America

OCIS Codes
(080.2740) Geometric optics : Geometric optical design
(110.2960) Imaging systems : Image analysis
(170.4460) Medical optics and biotechnology : Ophthalmic optics and devices

History
Original Manuscript: December 18, 2000
Revised Manuscript: June 8, 2001
Published: November 1, 2001

Citation
Yobani Mejía-Barbosa and Daniel Malacara-Hernández, "Object surface for applying a modified Hartmann test to measure corneal topography," Appl. Opt. 40, 5778-5786 (2001)
http://www.opticsinfobase.org/ao/abstract.cfm?URI=ao-40-31-5778


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References

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