Microscopic three-dimensional topometry with ferroelectric liquid-crystal-on-silicon displays.
When three dimensional measurements are conducted with fringe projection, the quality of the grating used for the generation of the fringes is important. It has a direct influence on the achievable depth resolution in a given measurement setup. In the past, Ronchi grating or gratings written in nematic liquid-crystal displays or in digital micromirror devices have been used. We report on the application of a reflective ferroelectric liquid-crystal-on-silicon display as the fringe-generating element in a setup based on a stereo microscope. With this device the depth resolution of measurements by use of phase-shifting algorithms can be significantly improved compared with the application of a Ronchi grating or a nematic liquid-crystal display.
Proll
Klaus-Peter
KP
Institut für Technische Optik, Universität Stuttgart, Pfaffenwaldring 9, 70569 Stuttgart, Germany. proll@ito.uni-stuttgart.de
Nivet
Jean-Marc
JM
Körner
Klaus
K
Tiziani
Hans J
HJ