The process and efficiency of ultraviolet generation from gallium nitride blue light emitting diodes

To obtain small size, high speed ultraviolet sources, we studied the ultraviolet (UV) generation process and efficiency of gallium nitride (GaN) blue light emitting diodes (LEDs). The blue and UV emissions follow a four-level recombination model. Depending on the pump pulse amplitude, the UV-to-blue generation ratio increases and then saturates with increasing pump pulse duration. High efficiency, up to 450 mu W UV power at 380 nm, can be obtained from a 1.2 mW blue LED. (C) 1997 American Institute of Physics.