| 摘要 |
PURPOSE:To read patterns with different kinds of gradation for plural chrominance components at high speed by performing the gradation correction on each image signal for the plural chrominance components independently by gradation correction characteristic. CONSTITUTION:Shading correction is applied to image output from a CCD at every color by a shading unit 28 in an image processing part 27, and it is gamma-corrected (gradation linearization) by a (gamma) correction unit 29, and is turbidity-corrected by a masking processing unit 30, and under color elimination correction is applied to it by a UCR processing unit 31. Furthermore, gradation reproduction correction is applied to the image output by a dither processing unit 32, and gradation increasing correction is applied to it by a multi-valued processing unit 33, and a laser 21 is modulated by a laser driver unit 34, then a laser beam is image-formed on a photosensitive drum. At this time, an electrostatic latent image is formed, and it is inputted to a developer of four colors. Every kind of processing can be performed by applying three-primary colors separation by a single operation of exposure scan, however, UCR processing output can be issued at every scan of B, G, R, and Bk(black). |
