Generation of coherent optical radiation by electronic means: the electro-optical parametric oscillator

We describe a novel external light control element that is capable of stabilizing both the amplitude and the frequency of an optical input field. A demanding application of this electro-optical parametric oscillator, conversion of incoherent inputs into coherent, phase-trackable outputs with small residual intensity modulation, is reported. Estimations show that commercially available light-emitting diodes have the potential to act as pump sources, although the incoherent optical input field used in these initial experiments was prepared by filtering of the coherent emission of a laser diode.