Numerical analysis of a chain-reaction H₂–Cl₂chemical laser

Abstract

The construction of a three-stage tunable birefringent filter using variable phase shifters fabricated from ammonium dihydrogen phosphate is described and its performance, evaluated for white light with a divergence of 2-3 mrad, is found to compare well with the predicted behaviour. A brief description of the principles of operation is included. Theoretically, the filter scans the spectrum from 250 nm to 750 nm with a bandwidth ranging in value from 35 nm at 250 nm to 85 nm at 750 nm. Theoretically, the voltage necessary to scan the above spectrum range is f 25 kV. Experimentally, a bandwidth ranging from 41 nm at 350 nm to 80 nm at 700 nm was obtained. Losses at various wavelengths have been determined. For example, at the centre wavelength (500 nm) where the bandwidth was 47 nm a ratio of Iout/Iin= 1/15 was obtained. Causes for deviation between theoretical and experimental results are examined and suggestions made for further work.