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An Auto-Focusing Method in Microscopic Testbed for Optical Discs



Xiao Tang, P L'Hostis, Y Xiao


An auto-focusing method is described and practically applied to an optical disc test-bed. In this application, an optical microscope was used to create clear pit images of optical discs. A CCD camera generated the graphic signals for the images. A standard deviation value of the gray levels for all pixels in the image is used as a feedback for auto-focusing control. The performance and possible applications of this method are discussed and test results for optical discs are given in this paper.
Journal of Research (NIST JRES) -
105 No. 4


auto-focus, disc testbed, optical discs, standard deviation


Tang, X. , L'Hostis, P. and Xiao, Y. (2000), An Auto-Focusing Method in Microscopic Testbed for Optical Discs, Journal of Research (NIST JRES), National Institute of Standards and Technology, Gaithersburg, MD (Accessed April 15, 2024)
Created July 1, 2000, Updated February 17, 2017