한국광학회지 (Korean Journal of Optics and Photonics)

  • 제31권3호
  • /
  • Pages.134-141
  • /
  • 2020
  • /
  • 1225-6285(pISSN)
  • /
  • 2287-321X(eISSN)
한국광학회 (Optical Society of Korea)
권호 표지
DOI QR코드

DOI QR Code

3차원 광학 측정을 위한 디지털 프린지 투사에 있어서 LCD 비선형 감마 에러 개선 방법

An Improved Method of LCD Gamma-nonlinearity Error Reduction in Digital Fringe Projection for Optical Three-dimensional Shape Measurement

  • Kim, Woo Sung (Department of Electronic Engineering, Suwon University)
  • 투고 : 2020.02.13
  • 심사 : 2020.03.16
  • 발행 : 2020.06.25
PDF 다운로드
⟨ 이전 논문 다음 논문 ⟩

초록

디지털 프린지 투사를 이용한 3차원 광학 측정시스템은 많은 비접촉 측정 응용에 사용된다. 수 ㎛까지 측정할 수 있는 이 시스템은 LCD를 사용하여 디지털 프린지 패턴을 생성한다. 이는 다양한 디지털 프린지 패턴을 컴퓨터 소프트웨어로 쉽게 만들 수 있기 때문이다. LCD 감마비선형에 의하여 물체에 투사된 디지털 프린지 패턴 에러는 3차원 물체 측정의 정확도에 영향을 준다. 정확도를 개선하기 위하여 광도전달함수(intensity transfer function)의 역함수를 사용하여 LCD 감마비선형에 의한 에러를 줄일 수 있는 개선된 방법을 제안하였다. 표준 반도체시편을 가지고 컴퓨터에서 생성한 사인파와 카메라에서 얻은 사인파의 차를 측정하여 제안한 방법의 개선효과를 보였다.

Optical three-dimensional (3D) measurement systems based on digital fringe projection are used in many contactless measurement applications. The system which can measure a dozen micrometers uses a liquid-crystal display (LCD) as the projection unit for generating a digital fringe pattern, because a flexible fringe pattern can be easily made by computer software. According to the gamma nonlinearity of the LCD projection unit, the digital fringe projection error on the object affects the accuracy of 3D object measurement. An improved method of LCD gamma-nonlinearity error reduction is proposed, by using the inverse function of the intensity transfer function to improve the accuracy. The improvement due to the proposed method is shown by measuring the difference in precision between a computer-generated sine wave and a camera-obtained sine wave for a standard semiconductor specimen.

키워드

참고문헌

  1. G. H. Notni and G. Nonti, "Digital fringe projection in 3D shape measurement: an error analysis," Proc. SPIE 5144, 372-380 (2003).
  2. Y. Choi, N. Park, and H. Kim, "High speed 3D inspection on wafer bump using White light scanning Interferometry," in Proc. The Korea Society of Manufacturing Technology Engineers Spring Meeting (Seoul Univ. of Science and Technology, Korea, May 2009), pp. 96-101.
  3. K. W. Ko, J. H. Sim, and M. Y. Kim, "A high-speed white-light interferometer for bump inspection of semiconductor manufacture," J. Korean Soc. Precis. Eng. 30, 702-708 (2013). https://doi.org/10.7736/KSPE.2013.30.7.702
  4. P. S. Huang, F. Jin, and F. P. Chiang, "Quantitative evaluation of corrosion by a digital fringe projection technique," Opt. Lasers Eng. 31, 371-380 (1999). https://doi.org/10.1016/S0143-8166(99)00019-6
  5. M. Dai, F. Yang, and H. Xiaoyuan, "Calibration of a fringe projection 3D measurement system using an equi-phase coordinate method based on two-reference-plane," Optics 4, 18-23 (2015). https://doi.org/10.11648/j.optics.s.2015040301.15
  6. R. Anchini, G. D. Leo, C. Liguori, and A. Paolillo, "A new calibration procedure for 3-D shape measurement system based on phase-shifting projected fringe profilometry," IEEE Trans. Instrum. Meas. 58, 1291-1298 (2009). https://doi.org/10.1109/TIM.2009.2012952
  7. H. Miao, C. Quan, C. J. Tay, and Y. Fu, "Analysis of phase distortion in phase-shifted fringe projection," Opt. Lasers Eng. 45, 318-325 (2007). https://doi.org/10.1016/j.optlaseng.2005.12.008
  8. C. A. Poynton, "SMPTE Periodical - SMPTE Tutorial: "Gamma" and its disguises: The nonlinear mappings of intensity in perception, CRTs, film, and video," SMPTE J. 102, 1099-1108 (1993). https://doi.org/10.5594/J01651
  9. C. R. Coggrave and J. M. Huntley, "High-speed surface profilometer based on a spatial light modulator and pipeline image processor," Opt. Eng. 38, 1573-1581 (1999). https://doi.org/10.1117/1.602209
  10. H. Guo, H. He, and M. Chen, "Gamma correction for digital fringe projection profilometry," Appl. Opt. 43, 2906-2914 (2004). https://doi.org/10.1364/AO.43.002906
  11. D. H. Kim, W. J. Ryu, N. K. Park, and Y. J. Kang, "A study on the calibration of shape measurement system using digital moire," in Proc. The Korea Society of Manufacturing Technology Engineers Spring Meeting (Korea, Apr. 2003), pp. 255-259.
  12. R. Talebi, A. Abdel-Dayem, and J. Johnson, "3-D reconstruction of objects using digital fringe projection: survey and experimental study," World Acad. Sci. Eng. Technol. 7, 1010-1019 (2013).