An inverse method for the design of TIR collimators to achieve a uniform color light beam

Color-over-angle (CoA) variation in the light output of white LEDs is a common and unsolved problem. In this article we introduce a new method to reduce CoA variation using a special collimator. The method is based on analytical inverse design methods. We present a numerical algorithm to solve the differential equations arising from this method and verify the results using Monte Carlo raytracing.