POLARIZATION EFFECTS IN MIRROR TYPE GONIOPHOTOMETERS

摘要

The international standard CIE S025:2015 "Test Method for LED Lamps, LED Luminaires and LED Modules" requires statements of the measurement uncertainty for all relevant quantities [1]. Measurement of luminous intensity distributions of large sized lamps and luminaires are typically performed using a mirror type goniophotometer. Major contributions of uncertainty specific to these types of devices are positioning accuracy, straylight, spectral matching and flatness of mirror. In this paper the effect of polarization is analysed and the contribution to the measurement uncertainty is estimated.