A single-stage modular modulator for pulsed illumination sources uses a full-range converter which converts unregulated DC to a 40-50 kHz carrier modulated at a frequency of a few hundred to a few thousand hertz. The modulated carrier is applied to the illumination source through a step-down...http://www.google.fr/patents/US5691607?utm_source=gb-gplus-shareBrevet US5691607 - Modular high power modulator
