Measurement of waveguide losses using a coherent fiber bundle

Abstract

The intensity profile of light scattered from a waveguide gives a measure of the total losses due to absorption and scatter. Measurement systems which rely on scanning probes suffer from severe alignment problems. A system is described which allows good spatial resolution and fast data acquisition. A coherent optical fiber bundle transfers the image of the scattered light to a detector or array of detectors. The technique may be extended to use computer acquisition of data from a CCD array. Results of measurements on ZnS waveguides are presented.