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Applied Optics

Applied Optics


  • Editor: Joseph N. Mait
  • Vol. 52, Iss. 35 — Dec. 10, 2013
  • pp: 8532–8539

Design of imaging keratometer with annular object and charge-coupled device detector

Yuanqing He, Yan Wang, Zhaoqi Wang, Yao Wang, Yongji Liu, Lin Zhang, Yi Zhai, and Shengjiang Chang  »View Author Affiliations

Applied Optics, Vol. 52, Issue 35, pp. 8532-8539 (2013)

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A novel imaging keratometer by the aid of modern optoelectronic technology is proposed. The optical system consists of an annular object, a first imaging subsystem, a second imaging subsystem, and a CCD detector. The measurement range of corneal refraction is from 30D to 60D (5.5–11 mm in radius of curvature), and the accuracy reaches 0.156D, 0.072D, and 0.036D, respectively, for the corneal surface of the steepest, the radius of curvature of 7.8 mm, and the corneal surface of the flattest. The accuracy of corneal astigmatism is verified to be 0.05D for cylindrical refraction of 0.75D. Compared with the traditional keratometer, the proposed keratometer possesses advantages of high accuracy.

© 2013 Optical Society of America

OCIS Codes
(120.3890) Instrumentation, measurement, and metrology : Medical optics instrumentation
(330.7327) Vision, color, and visual optics : Visual optics, ophthalmic instrumentation

ToC Category:
Medical Optics and Biotechnology

Original Manuscript: August 19, 2013
Revised Manuscript: November 4, 2013
Manuscript Accepted: November 5, 2013
Published: December 6, 2013

Virtual Issues
Vol. 9, Iss. 2 Virtual Journal for Biomedical Optics

Yuanqing He, Yan Wang, Zhaoqi Wang, Yao Wang, Yongji Liu, Lin Zhang, Yi Zhai, and Shengjiang Chang, "Design of imaging keratometer with annular object and charge-coupled device detector," Appl. Opt. 52, 8532-8539 (2013)

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