Patent ID: 7928671

Claim:
A method of controlling current, comprising: adjusting an illumination intensity, including providing a plurality of unit pulses during a plurality of consecutive time intervals, wherein each unit pulse of the plurality of unit pulses has a fixed on-time of a first duration and a fixed off-time of a second duration, wherein each time interval of the plurality of consecutive time intervals is of a third duration, and wherein providing the plurality of unit pulses includes: providing a first determined number of unit pulses of the plurality of unit pulses during a first time interval of the plurality of consecutive time intervals; and providing a second determined number of unit pulses of the plurality of unit pulses during a second time interval of the plurality of consecutive time intervals, wherein the second determined number of unit pulses of the plurality of unit pulses is different from the first determined number of unit pulses of the plurality of unit pulses, and wherein the first determined number is not zero and the second determined number is not zero.