Patent ID: 6414652
Filing Date: 2002-07-02
Classification: H04N

Abstract:
A color image reading apparatus comprising:a first lighting controller which, in full-color reading, successively turns on a red light emitting diode, a green light emitting diode and a blue light emitting diode as reading light sources each for a predetermined period; a variable current regulating circuit for supplying current to the light emitting diodes; a first light output controller combined with the current regulating circuit for setting light output of each light emitting diode, which is turned on by the first lighting controller, to a first predetermined level in full-color reading; a second lighting controller for continuously turning on one of the light emitting diodes in monochrome reading; and a second light output controller combined with the current regulating circuit for setting, in monochrome reading, light output of said one light emitting diode, which is turned on continuously by the second lighting controller, to a second predetermined level less than the first predetermined level.