Acquisition of Color Image Using a Monochrome Camera in White-Light Interferometer

Abstract

In this research, it is suggested to acquire a color image using a monochrome camera from white-light scanning interferometer without any hardware modification and addition. Previous research is necessarily required to install a color camera and other optical system change. Therefore, this research aims to obtain the spectral intensity of interferogram by Fourier transform from existing monochrome camera. Since the intensity also includes reference mirror component, it is removed by measuring silicon sample which is known its reflection coefficient. After RGB filtering of acquired sample intensity, it is converted to 8-bit digital value and the whole surface is expressed as color image by applying the above process to each pixel. Lastly, 3 samples color images are obtained and they are evaluated by PSNR. It is verified that the color can be recognized by color acquisition method meeting up at least 24dB. This research is expected to reduce hardware cost and obtain color image by the software process. The acquired color image helps understanding of sample intuitively and can be utilized for sample review, target positioning and pattern matching.