CHARACTERIZATION OF A TRANSFORMATION FUNCTION OF A PHOTOCHROMIC ADAPTIVE FILTER

Simple, fast and accurate procedure is developed for measuring a Trans formation Function (TF) of a Photochromic Adaptive Filter (PAF). Photo chromic filters, whose spectral transmittance depends on previous and immediate radiant exposure and other environmental conditions, require special methods of spectrophotometry to determine their properties. T his article describes methodology of characterizing the luminous trans mittance as a function of light intensity using easy to implement meth od. Transformation functions of sample filters for different sources o f radiation and varied light intensity are evaluated. The measuring sy stem can also be used for fast determination of spatially and spectral ly uniform light sources with UV spectral component.