한국정밀공학회지 (Journal of the Korean Society for Precision Engineering)

  • 제26권5호
  • /
  • Pages.72-78
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  • 2009
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  • 1225-9071(pISSN)
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  • 2287-8769(eISSN)
한국정밀공학회 (Korean Society for Precision Engineering)
권호 표지

다파장 광원을 이용한 위상 물체의 2 차원 굴절률 분포와 두께 측정을 위한 분리 알고리즘

Separation Algorithm for 2D Refractive Index Distribution and Thickness Measurement of Transparent Objects using Multi-wavelength Source

  • 이광천 (한국과학기술연구원 기계항공시스템공학부 기계공학과) ;
  • 류성윤 (한국과학기술연구원 기계항공시스템공학부 기계공학과) ;
  • 이윤우 (한국표준과학연구소) ;
  • 곽윤근 (한국과학기술연구원 기계항공시스템공학부 기계공학과) ;
  • 김수현 (한국과학기술연구원 기계항공시스템공학부 기계공학과)
  • 발행 : 2009.05.01
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초록

We propose the separation algorithm to simultaneously measure two-dimensional refractive index distribution and thickness profile of transparent samples using three wavelengths. The optical system was based on the Mach-zehnder interferometer with LD (Laser Diode)-based multi-wavelength sources. A LCR (Liquid Crystal Retarder) was used to obtain interference images at four phase states and then the optical phase of the object is calculated by four-bucket algorithm. Experimental results with a glass rod are provided at the different wavelengths of 635nm, 660nm and 675nm. The refractive indices of the sample are distributed with accuracy of less than 0.0005 and the thickness profile of sample was cylindrical type. This result demonstrates that it is possible to separate refractive index distribution and thickness profile of samples in two dimensions using the proposed algorithm.

키워드

참고문헌

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