상세정보
학술대회
Multi-incident Holography Profilometry for Low and High Gradient Object
- 저자
- Moncy S. Idicula, Patryk Mitura, Michał Jozwik, 추현곤, Juan Martinez-Carranza, Kai Wen, Tomasz Kozacki
- 발행일
- 202205
- 출처
- SPIE Photonics Europe 2022 (SPIE 12138), pp.1-9
- 협약과제
- 22HH5700, 홀로그램 기반의 위상 검출용 디지털 홀로그래피 메트롤로지 기술 개발, 임용준
- 초록
- Digital holographic microscopy (DHM) is a non-contact, profilometric tool that allows obtaining microscopic object topography from captured holograms. However, the use of DHM is limited when the object under observation has a high gradient or is discontinuous. Multi-angle digital holographic profilometry (MIDHP) is an alternative solution for overcoming this limitation for measuring the topography with discontinuities. This method combines digital holography and multi-angle interferometry. The method requires a certain number of holograms that are processed into longitudinal scanning function (LSF). The topography of the object is recovered by finding the maxima of the LSF. MIDHP enables to enlarge the measurement range and provides a high axial resolution. This paper investigates MIDHP to measure surfaces with various (low and high) surface gradients. The calculations of LSF requires many Fourier Transforms (FT) and the computations are slow. In this paper, we improve LSF calculations by introducing two algorithms. The first algorithm reduces number of FT needed by applying summation in frequency domain. Second approach applies the method of 3D filtering, which improves the quality of the reconstructed shape. The introduced approaches are verified both numerically and experimentally.
- KSP 제안 키워드
- 3D filtering, Axial Resolution, Digital Holographic Microscopy(DHM), High gradient, Measurement range, Multi-angle, Non-contact, digital holography, fourier transform, frequency domain(FD), surface gradients