DOI QR코드

DOI QR Code

이중푸리에변환을 이용한 2 파장 디지털 홀로그래픽 연구

Study on the Two-wavelength Digital Holography Using Double Fourier Transform

  • 투고 : 2010.04.26
  • 심사 : 2010.06.01
  • 발행 : 2010.06.25

초록

디지털 홀로그램을 이용하여 상을 재생 할 때 재생상의 크기는 재생거리와 파장의 함수이다. 이러한 재생거리와 파장 의존성을 제거하기 위하여 이중푸리에변환법이 제안되었고, 이중푸리에변환을 이용하면 일정 크기의 재생상을 얻을 수 있다. 일반적으로 사용된 광원의 파장보다 큰 단차의 높낮이 측정은 단일파장 디지털 홀로그래픽 방식으로 측정이 가능하지 않기 때문에 2 파장홀로그래피가 제안되었는데, 두 파장에서 얻어진 각각의 재생상의 크기가 같아야 하는 제약이 있다. 본 연구에서는 투과 및 반사형 2 파장 디지털 홀로그래픽 현미경을 이용하여 각각의 파장별로 홀로그램을 촬영하고 이중푸리에변환을 이용하여 재생함으로써 두개의 파장에서 얻어진 재생상의 크기를 같게 만들어 주는 과정 없이 단차를 가진 샘플의 3차원 높낮이 측정을 할 수 있었다.

The size of a reconstructed image depends on the reconstruction distance and wavelength. The double fourier transform method is proposed to eliminate the dependence on the reconstruction distance and wavelength. We can get a fixed reconstructed image size by using the double fourier transform method. Two wavelength digital holography is proposed to measure the step height, which is larger than a single wavelength. The two image size of different wavelength holograms should be the same in order to apply two wavelength digital holography. We use two wavelength digital holography and double fourier transforms to measure the step height. The measured data were reasonable and we found that the double fourier transform is useful in two wavelength digital holography.

키워드

참고문헌

  1. J. W. Goodman and R. W. Lawrence, “Digital image formation from electronically detected holograms,” Appl. Phys. Lett. 11, 77-79 (1967). https://doi.org/10.1063/1.1755043
  2. M. A. Kronrod, N. S. Merzlyakov, and L. P. Yaroslavski, “Reconstruction of hologram with a computer,” Sov. Phys. Tech. 17, 434-444 (1972).
  3. G. K. Wernicke, O. Kruschke, N. Demoli, and H. Gruber, “Investigation of-micro-opto-electro-mechanical components with a holographic microscopic interferometer,” Proc. SPIE 3396, 238-243 (1998). https://doi.org/10.1117/12.301528
  4. L. Xu, X. Peng, J. Miao, and K. Asundi, “Studies of digital microscopic with application to microstructure testing,” Appl. Opt. 40, 5046-5051 (2001). https://doi.org/10.1364/AO.40.005046
  5. S. Kim, H. Lee, and J. Son, “Recording of larger object by using two confocal lenses in digital holography,” Hankook Kwanghak Hoeji (Korean J. Opt. Photon.) 14, 244-248 (2003). https://doi.org/10.3807/KJOP.2003.14.3.244
  6. U. Schnars, “Direct phase determination in hologram interferometry with use of digitally recorded holograms,” J. Opt. Soc. Am. A11, 2011-2015 (1994).
  7. C. Wagneer, S. Seebacher, W. Osten, and W. Juptner, “Digital recording and numerical reconstruction of lensless Fourier holograms in optical metrology,” Appl. Opt. 38, 4812-4820 (1999). https://doi.org/10.1364/AO.38.004812
  8. Y. Takaki and H. Ohzu, “Fast numerical reconstruction technique for high resolution hybrid holographic microscopy,” Appl. Opt. 38, 2204-2055 (1999). https://doi.org/10.1364/AO.38.002204
  9. L. Xu, J. Miao, and A. Asundi, “Properties of digital holography based on in-line configuration,” Opt. Eng. 39, 3214-3219 (1999). https://doi.org/10.1117/1.1327503
  10. K. Creath, Y. Chengi, and J. C. Wyant, “Contouring aspheric surfaces using two-wavelength phase-shifting interferometry,” Optica Acta 32, 1455-1464 (1985). https://doi.org/10.1080/713821689
  11. J. Gass, A. Dakoff, and M. K. Kim, “Phase imaging without $2{\pi}$ ambiguity by multiwavelength digital holography,” Opt. Lett. 28, 1141-1143 (2003). https://doi.org/10.1364/OL.28.001141
  12. F. Zhang and I. Yamaguchi, “Algorithm for reconstruction of digital holograms with adjustable magnification,” Opt. Lett. 29, 1688-1670 (2004).
  13. J. W. Goodman, Introduction to Fourier Optics (Roberts & Company Publishers, USA, 2005).