Application of a laser heterodyne detector in submillimeter wave spectroscopy with a harmonic generator

Spatial sensitometry variations in a liquid crystal light valve are studied as well as signal induced noise and differences in global and local contrast ratio. The device's off state is investigated and spatial variations in the thickness of the LC layer are used to quantify the results obtained. Operation with low frequency applied ac voltages appears preferable from noise considerations, whereas operation at high frequency appears preferable for improved uniformity.