Generating a True Color Image with Data from Scanning White-Light Interferometry by Using a Fourier Transform

  • Kim, Jin-Yong (School of Mechanical and Aerospace Engineering, Seoul National University) ;
  • Kim, Seungjae (Sindoh Co., Ltd.) ;
  • Kim, Min-Gyu (School of Mechanical and Aerospace Engineering, Seoul National University) ;
  • Pahk, Heui Jae (School of Mechanical and Aerospace Engineering, Seoul National University)
  • Received : 2019.04.30
  • Accepted : 2019.06.05
  • Published : 2019.10.25


In this paper we propose a method to generate a true color image in scanning white-light interferometry (SWLI). Previously, a true color image was obtained by using a color camera, or an RGB multichannel light source. Here we focused on acquiring a true color image without any hardware changes in basic SWLI, in which a monochrome camera is utilized. A Fourier transform method was used to obtain the spectral intensity distributions of the light reflected from the sample. RGB filtering was applied to the intensity distributions, to determine RGB values from the spectral intensity. Through color corrections, a true color image was generated from the RGB values. The image generated by the proposed method was verified on the basis of the RGB distance and peak signal-to-noise ratio analysis for its effectiveness.


Scanning white-light interferometry;Metrology;True color;Fourier transforms


Supported by : Seoul National University


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