Patent ID: 6741041
Filing Date: 2004-05-25
Classification: G11B,H05B

Abstract:
A power controller for controlling a power of light emitted from a light source, comprising:target value setting unit for setting a plurality of target values; a plurality of feedforward unit, provided corresponding to each of said plurality of target values, for generating feedforward currents corresponding to each of said target values; first switching unit for allowing the respective feedforward currents generated by said plurality of feedforward unit to be exclusively switched and then supplied to said light source; second switching unit for allowing said plurality of target values to be exclusively switched for output; and feedback unit for supplying a feedback current to said light source, the feedback current having been adjusted such that a difference between the power of light emitted from said light source and a target value output by said second switching unit is stabilized at a predetermined value, wherein upon changing each of said target values, said first switching unit and said second switching unit are switched simultaneously corresponding to a target value changed.