Abstract (EN):
Dither demodulation of fibre Bragg grating sensors illuminated with multimode light from cheap compact disc laser diodes is investigated. Quasi-static temperature and strain sensitivities of 0.09 degrees C/root Hz and 0.6 mu epsilon/root Hz are obtained. It is shown that small ac signals outside the loop bandwidth can be measured using synchronous detection at double the dither frequency.
Language:
English
Type (Professor's evaluation):
Scientific