한국광학회지 (Korean Journal of Optics and Photonics)

  • 제20권2호
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  • Pages.81-86
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  • 2009
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  • 1225-6285(pISSN)
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  • 2287-321X(eISSN)
한국광학회 (Optical Society of Korea)
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굴절률 차이와 디지털 홀로그래피를 이용한 큰 단차측정

Height Measurement by Refractive Index Difference and Digital Holography

  • 발행 : 2009.04.25
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⟨ 이전 논문 다음 논문 ⟩

초록

디지털 홀로그램과 굴절률 차이를 이용하여 사용된 광원의 파장보다 큰 단차를 측정하는 연구를 하였다. 위상차를 측정하여 단차를 측정하는 방식에서는 위상차가 $2{\pi}$보다 큰 경우에는 원리상 단차를 구하기 어렵다. 이를 보완하기 위하여 굴절률 차이를 이용하여 인위적으로 광경로차를 줄여 파장보다 큰 단차를 측정할 수 있는 디지털 홀로그래피 시스템을 구성하였고, 실험적으로 파장의 약 3배 이상의 단차를 측정하였다.

Digital holography and refractive index difference are used to measure a high aspect ratio's patterns. When interference fringes are very closely spaced, the phase data containing high frequencies where $2{\pi}$ ambiguities cannot be resolved. In this technique, the optical path difference is decreased by decreasing the refractive index difference. As a result, we solve the $2{pi}$ ambiguities. Also, this technique is applicable to measure the refractive index if the shape of the sample is known.

키워드

참고문헌

  1. J. W. Goodman and R. W. Lawrence, 'Digital image formation from electronically detected holograms,' Appl. Phys. Lett., vol. 11, no. 3, pp. 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., vol. 17, no. 2, pp. 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, vol. 3396, pp. 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., vol. 40, no. 28, pp. 5046-5051, 2001 https://doi.org/10.1364/AO.40.005046
  5. H. Cho, D. Kim, Y. Yu, W. Jung, and S. Shin, '3-dimensional measurement using digital holographic microscope and phase unwrapping,' 한국광학회지, 제 17권 4호, pp. 329-334, 2006 https://doi.org/10.3807/KJOP.2006.17.4.329
  6. H. Cho, D. Kim, Y, Yu, S. Shin, W. Jung, and J. Son, 'Twin image elimination in an in-line digital holographic microscope,' J. Korean Phys. Soc., vol. 52, no. 4, pp. 1031-1035, 2008 https://doi.org/10.3938/jkps.52.1031
  7. U. Schnars, 'Direct phase determination in hologram interferometry with use of digitally recorded holograms,' J. Opt. Soc. Am. A, vol. 11, no. 7, pp. 2011-2015, 1994 https://doi.org/10.1364/JOSAA.11.002011
  8. C. Wagneer, S. Seebacher, W. Osten, and W. Juptner, 'Digital recording and numerical reconstruction of lensless fourier holograms in optical metrology,' Appl. Opt., vol. 38, no. 22, pp. 4812-4820, 1999 https://doi.org/10.1364/AO.38.004812
  9. Y. Takaki and H. Ohzu, 'Fast numerical reconstruction technique for high resolution hybrid holographic microscopy,' Appl. Opt., vol. 38, no, 11, pp. 2204-2055, 1999 https://doi.org/10.1364/AO.38.002204
  10. L. Xu, J. Miao, and A. Asundi, 'Properties of digital holography based on in-line configuration,' Opt. Eng., vol. 39, no. 12, pp. 3214-3219, 1999 https://doi.org/10.1117/1.1327503
  11. K. Creath, Y. Cheng, and J. C. Wyant, 'Contouring aspheric surfaces using two-wavelength phase-shifting interferometry,' Optica Acta, vol. 32, no. 12, pp, 1455-1464, 1985 https://doi.org/10.1080/713821689
  12. I. Yamaguchi, T. Ida, M. Yokota, and K. Yamashita, 'Surface shape measurement by phase-shifting digital holography with a wavelength shift,' Appl. Opt., vol. 45, no. 29, pp. 7610-7616, 2006 https://doi.org/10.1364/AO.45.007610
  13. J. Kuhn, 'Measurements of corner cubes microstructures by high magnification digital holographic microscopy,' Photonics Europe 2006, Strasbourg, France, 2006
  14. J. W. Goodman, Introduction to Fourier Optics (Roberts & Company Publishers, USA, 2005)
  15. E. Cuche, P. Marquet, and C. Depeursinge, 'Simultaneous amplitude-contrast and quantitative phase-contrast microscopy by numerical reconstruction of fresnel off-axis holograms,' Appl. Opt., vol. 38, no. 34, pp. 6994-7001, 1999 https://doi.org/10.1364/AO.38.006994