Separation of measurement of the refractive index and the geometrical thickness by use of a wavelength-scanning interferometer with a confocal microscope.
An improved system for the separate measurement of the refractive index and the geometrical thickness that constitutes a hybrid configuration of a confocal microscope and a wavelength-scanning heterodyne interferometer with a laser diode is presented. The optical path difference can be measured in less than 1 s, which is 10 times quicker than with the low-coherence interferometry previously used, and with a resolution of 10 microm with a fixed reference mirror. Separate measurement of the refractive index and the geometrical thickness of glass plates was demonstrated by use of the arrangement in place of the low-coherence interferometer used previously.
Fukano
T
T
Graduate School of Science and Engineering, Saitama University, 225 Shimo-Okubo, Urawa, Saitama 338-8570, Japan. tenchan@optsun.riken.go.jp
Yamaguchi
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I