Spectrum matching on the test of luminance gain of image intensifier

Luminance gain is one of the evaluation parameters for light quantum performance of image intensifier. In the traditional testing methodology of the luminance gain of image intensifier, the result is obtained only by measuring the incident and emergent radiation without considering the spectrum matching. In this paper, the expression of luminance gain is presented by considering the spectral visibility function and spectral character of incident and emergent radiation. Thus a corrective factor is deduced in detail for the practice application pattern. And the adjusted testing methodology of luminance gain of intensifier is studied and realized in a digitized integral system. The results after long running period are compared with those of routine measurements. And the factors that affect the measurement accuracy are analyzed. The results show that the adjusted test methodology has high measurement precision and stability. The methodology can also be used to evaluate such performance of similar imaging devices after adjusting the illuminance source unit.