Patent ID: 8482823
Filing Date: 2013-07-09
Classification: H04N

Abstract:
1. A contact-type image scanner, comprising: an illumination unit comprising a first light source, a second light source and a third light source for respectively emitting different color light beams on an original surface; a control unit in communication with said illumination unit for controlling on durations of said first light source, said second light source and said third light source, wherein in response to a first start pulse, said first light source is turned on for a first on duration, in response to a second start pulse, said second light source is turned on for a second on duration, and in response to a third start pulse, said first, second and third light sources are simultaneously turned on for a first minor on duration, a second minor on duration and a third minor on duration, respectively, wherein said second light source is turned on immediately after said first light source is turned off or after said first light source is turned off for a delaying time; and a photo-sensing unit for receiving said light beams reflected from said original surface and outputting an image message, wherein said photo-sensing unit obtains a first image data value during said first on duration, obtains a second image data value during a second on duration and obtains a third image data during said first, second and third minor on durations.