Canon imageFORMULA DR-C125 Service Manual

Also see for imageFormula DR-C125: Brochure & specs Brochure & specs Pocket guide User manual Operation guide

CHAPTER 2 FUNCTIONS & OPERATIONII. READING SYSTEM1. Reading UnitThe sectional view of the readingsystem is shown below. The reading units(front and rear) have the same configurationbut the different holder shapes.Reading unit(front)DocumentReading unit(rear)Figure 2-201This configuration with two opposingreading units enables the machine to readboth front and rear sides of a document in asingle scan.The read image data are sent to theimage processing section of the controlPCB.To prevent reading speed fromdecreasing, the image data is divided intothree and output in parallel.The reading unit consists of CIS unit,holder, and case.The CIS unit consists of CIS PCB, lensarray, LED (R/G/B), light guide, and case.The reading glass and white referencesheet are mounted on the holder.Photosensitive pixels are mounted onthe CIS PCB with a density of 600 dpi in aline. The effective reading width is 216 mm,and the number of effective pictureelements is 5107.A set of three basic color LEDs, red,green, and blue (RGB), is mounted only onthe one side. This single-side illuminationcauses a shadow on a document, whichmay effect on the image data quality.In the binary or grayscale modes, imagedata are read with composite lightgenerated by lighting the RGB LEDs at thesame time. In the color mode, the LED issuccessively lit, and reads image data witheach color. As documents are being fed atregular speed while image data are read,the reading positions of RGB are shiftedslightly.In the color dropout mode, only the LEDof a designated color lights. In the coloremphasis mode, the LED of a color otherthan a designated color lights.2-6 COPYRIGHT © CANON ELECTRONICS INC. 2011 CANON DR-C125 FIRST EDITION