Thickness and Refractive Index Measuring Arrangement as a first Stage for an Optical Coherence Tomography System

Abstract

This work deals with the first step of optical image technique called optical coherence tomography (OCT), an interferometric imaging technique that provides cross-sectional views of the subsurface microstructure of a sample. Following a discussion of the basic theory of OCT, an overview of the issues involved in the design of the main components of OCT system is presented. Also, a Michelson interferometer with scanner unit (digital CCD camera and photodetector with oscilloscope) was used, and the shift in the circular fringes was used to measure the thickness and refractive index of transparent materials through the mathematical relation between the differences of the number of fringes before and after putting the transparent glass plate and thickness.