<title>Time-resolved measurements of the spectra of a broadband laser used as light source for the coherence radar</title>

Abstract

For coherence radar measurements of lateral ranges of more than 10 X 10 cm<SUP>2</SUP> broadband light sources with average output powers of several 100 mW in the visible spectral range are needed. This micrometer-scale 3D-imaging technique using the Michelson interferometer technique with low coherence light sources is described in recent papers. The depth resolution is limited by the coherence length of the incident light. That is why light sources with a broad emission spectrum are useful. With the commonly used light sources, e.g. conventional lamps and superluminescent diodes, it is not possible to measure dark and strongly curved objects with a large lateral field of view. This problem is solved by a powerful, broadband laser in fundamental mode operation. The method to obtain a light source with a broad emission spectra presented in this paper is by gain switching a Ti:sapphire laser.