Emission characteristics of high power LEDs studied by confocal microscopy

We have developed a method that allows us to measure the emission profiles of millimetre-sized high-power light emitting diodes with micron resolution. The optical cross-sections recorded provide detailed information on the light intensity distribution of LEDs within the substrate till a distance of several tens of millimetres, which can be used to map out strategies for an optimization of the power efficiency or the tailoring of the light distribution of high power LEDs.