MEASUREMENT OF THICKNESSES OF OPTICALLY TRANSPARENT LAYERED STRUCTURES BY THE SPECTRAL INTERFEROMETRY METHOD

Abstract

The results of applying the method of spectral interferometry in optical band for measuring the thicknesses of thin films are presented in this paper. We have analyzed analytically and experimentally the spectrum of the total radiation at the output of the fiber optic Fabry-Perot interferometer which is formed by broadband light reflections from the multilayer structures, including the special case of two reflections when the object of study are the thin films. The spectrum informative components corresponding to the distances to the reflective surfaces have been obtained. The results of experiments conducted using broadband LED light sources of optical radiation are in full agreement with the results which were obtained theoretically. A software tool with a graphical user interface for processing and visualization of the experimental results has been developed. The obtained results will help improve the performance of the measuring equipment in medicine, profilometry, and create standards for metrology.

Keywords

• double spectral analysis
• fiber optic interferometer
• led
• noise radar technology
• secondary spectrum
• spectral interferometry method
• thin films