Responses to light and radiation: a guide to units,conversion factors and computations

Abstract

The paper gives explicit instruction on numerical procedures applicable in photometry and radiometry, for example in deriving the spectral power distribution of a source from spectrophotometric comparison with an existing standard, the luminous efficacy of a radiation, responses of detectors including the 'photometric eye', and in the various conversions of such responses from one basis to another. With an introduction on the relation between photometry and radiometry, particularly as regards units, and with mention of the special problems of biological and photographic responses, it is intended as a practical guide for those whose work overlaps these various fields or who may be unfamiliar with the basic radiometric concepts. It includes a table of values of K(x) and of the luminous efficacy of black-body radiations over the range 1800 to 3400 K.