A light emitting diode (LED) driving apparatus includes a drive section for driving an LED to emit light, and a control section that controls a driving current supplied from the drive section to the LED. The control section implements luminous power control by controlling an ON/OFF ratio of the driving...http://www.google.de/patents/US7916101?utm_source=gb-gplus-sharePatent US7916101 - LED driving apparatus and method of controlling luminous power
