Canon DR-9080C Service Manual

Also see for DR-6080: Quick reference Instructions Maintenance Guide

Contents

COPYRIGHT © 2003 CANON ELECTRONICS INC. CANON DR-6080/9080C REV.0 SEPT. 2003 2 - 9CHAPTER 2 FUNCTIONS & OPERATION2. Reading Unit ConfigurationFig. 2-204 is a sectional diagram of thereading unit. The reading unit consists of thesensor drive PCB, image sensor PCB, lens array,LEDs (R/G/B), light guide, and reading glass.The contact image sensors (CIS) are mountedon the image sensor PCB in a single row, with adensity of 600 dpi. The valid reading width is 305mm, and the number of valid pixels is 7260. Theoptical resolution can be switched between 600 dpiand 300 dpi by an external signal.The main feature of this reading unit is that itprovides lighting for the image sensors using twoLEDs, lighting the document from both the rightand left sides as shown in the figure. The lightguides are arranged on the right and left side, anda red (R), green (G), and blue (B) LED is arrangedfor each light guide on the image sensor PCB.LEDs light illuminate the document throughthe light guides, and the light reflected from thedocument enters the image sensors through thelens array. The image sensors convert the light toan analog signal. The analog signal is sent to thesensor drive PCB, and then to the main CPU PCBas a digital signal after A/D conversion andshading correction.In the binary or grayscale mode, the image isread with composite light generated by lighting allthe RGB LEDs simultaneously. In the color mode,the RGB LEDs are sequentially lit, and the imagedata is read separately for each color. In thedrop-out color mode, only the LEDs of thedesignated color are lit.In the previous models (DR-5020/5080C), A/Dconversion and shading correction were handledby the image processor on the main CPU PCB, butin this model they are processed internally by thereading unit.Reading glassSensor drive PCBImage sensorPCBImage sensor (CIS)Light guideLight guideLens arrayLEDs (R/G/B)LEDs (R/G/B)DocumentFig. 2-204