Multiplex advantage in Hadamard transform spectrometry utilizing solid-state encoding masks with uniform, bistable optical transmission defects

The effect of a uniform bistable optical transmission defect in the encoding mask on the multiplex efficiency is investigated for solid-state Hadamard transform spectrometry with thermal detection. It is demonstrated that encoding masks which possess nonideal optical transmission properties, i.e., bistable transmission defects, need not impare the multiplex capability provided a sufficient number of resolution elements are multiplexed. Application to the SNR of a general algorithm for the calculation of the average mean square error in the estimate of the spectrum shows that reasonable SNR improvements can be expected when compared to conventional dispersive instruments.