Evaluation of emissive infrared projector radiant output parameters

The output from an infrared projector can be characterized in terms of either output signal radiance or effective blackbody temperature. In this paper, expressions from which both parameters may be derived are developed by spectral analysis of the infrared system comprised of an emissive infrared projector and an imaging unit under test (UUT). Features of the analysis include the separation of the infrared projector characteristics from those of the UUT, the calculation of the output signal radiance in terms of standard blackbody radiation formulae and the inherent algebraic connection that is maintained, enabling the UUT signal current to be readily determined once the output signal radiance is known. A dimensionless graphical procedure is developed for the subsequent determination of the effective blackbody temperature.