29 December 1998 Two-frequency phase-shifting projection moire topography
Author Affiliations +
Proceedings Volume 3520, Three-Dimensional Imaging, Optical Metrology, and Inspection IV; (1998) https://doi.org/10.1117/12.334348
Event: Photonics East (ISAM, VVDC, IEMB), 1998, Boston, MA, United States
Abstract
Adopting phase-shifting technique in moire topography provides many advantages in measuring complex surface profiles with varying reflectance. However, still the so- called 2(pi) -ambiguity problem remains, which limits the maximum measurable step height difference between two neighboring sample points to be less than half the equivalent wavelength of moire fringes. To cope with the problem in this investigation, a two-wavelength scheme of projection moire topography is proposed along with necessary hardware design considerations. Test results prove that the proposed scheme is capable of finding absolute fringe orders automatically, so that the 2(pi) -ambiguity problem can be effectively overcome so as to treat large step discontinuities in measured surfaces.
© (1998) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Seung-Woo Kim, Jung-Taek Oh, Moon-Sik Jung, Yi-Bae Choi, "Two-frequency phase-shifting projection moire topography", Proc. SPIE 3520, Three-Dimensional Imaging, Optical Metrology, and Inspection IV, (29 December 1998); doi: 10.1117/12.334348; https://doi.org/10.1117/12.334348
PROCEEDINGS
7 PAGES


SHARE
Back to Top