PUB - Publikationen an der Universität Bielefeld

Novel interferometers for length and displacement measurements based on sampling an optical standing wave will be presented. The interference of two laser beams propagating in opposite direction results in a sinusoidal light intensity profile, which can be detected by thin transparent photodiodes based on amorphous silicon. Two individual detectors positioned on he optical axis of a standing wave allow bi-directional fringe counting. The operation principle of set-ups consisting of two individual nip-photodiodes on one hand and a phase sensitive transparent photodiode based on two integrated nip-diodes on the other hand will be discussed. With both set-ups Lissajous figures are detected demonstrating the feasibility of the new concept for length and displacement measurements.