METROLOGY FOR LED LAMPS AND MODULES

(1)An integrating sphere with a spectrometer is the recommended instrument for the measurements of LED lamps and modules. A new coating solution for the integrating spheres with an optimum coefficient of reflectance will be presented as a compromise between the sensitivity of the sphere to contamination and aging and the directional dependence during the measurement. It will be shown, that prior stabilisation of the lamp and the correction of its self-absorption are crucial for the measurements of SSL light sources in the middle of integrating sphere (4 pi). Large lamps with forward directed light should be measured on the side port of the sphere in the 2 pi geometry due to large self-absorption when placed at the sphere centre.