Etendue analysis and measurement of light source with elliptical reflector

The efficiency and lumen output of light source for illumination system were analyzed based on Etendue, this analytical approach can predict light source collection efficiency. A new method for measuring the output intensity distribution of light source with elliptical reflector was put forward; the collection efficiency vs. Etendue curve was estimated with this technique. The Etendue was changed by moving the mobile aperture gradually and the intensity distributions were recorded by CCD camera in this measurement method. The method is very convenient and the experimental result matches well with the theoretical model.