Light collection engines with micro compound-eye arrays for pico-projection displays

摘要

Light emitting diodes (LEDs) have recently gained much interest as projection light sources due to their long lifetimes, large color gamut, small size, and absence of mercury vapor. In this work, a compound parabolic concentrator (CPC) coupled to a compound-eye array is designed and fabricated as a light collection engine of LED-based pico-projection diaplay. The results indicate that more than 90% light can be collected by the CPC coupled to a compound-eye array and transmitted within the designed angle. This method is advantageous in many respects compared with those available, such as compact volume, high collection efficiency, rectangular radiation pattern and controllable output divergence angle. These features and results validate the potential of a CPC coupled to a compound-eye array as a light collection engine of pico-projection display application.