NEAR FIELD CHARACTERIZATION OF LED SOURCES WITH FOURIER OPTICS INSTRUMENT

摘要

We describe a new method based on Optical Fourier Transform (OFT) system that allowsrnobtaining near field luminance and color distribution of all types of light sources. The lightrndistribution of one virtual small emission spot is measured in quasi all the hemisphere withinrnseconds. A simple XY stage moving the light source in front of the system is used to map arnsurface adapted to the total size of the source. Detailed near field color and luminancerndistribution model is then deduced with very high angular resolution and can be directlyrnconverted to ray sets for optical design. The method is applied to LED sources to obtain veryrnprecise near field emission diagram with high spatial and angular resolutions.