<title>Wavelength scanning confocal interference microscope for separate measurement of refractive index and geometrical thickness</title>

Abstract

We previously proposed a system based on a combination of a confocal microscope and a wavelength scanning heterodyne interferometer, for separate measurement of refractive index and geometrical thickness of lens and plates. However, we used two optical systems successively although they share the same optical system. In this paper, we propose a new measurement scheme which enable us to measure both the confocal profile and the optical path difference of the interferometer by single scanning of an object. We describe here the measurement principle, the apparatus, signal processing means, and some experimental results.

A glass thickness measuring system using the machine vision method

“…Thus, that results in an inconvenience to align because of the refraction of laser. 3 Also, the other methods have a vital error for using in vibrating environment such as continuous glass sheet production line. In the method, two probes data are collected in order, separately, and the error due to the different time sampling is included.…”