2. Blanking (Whiting) of Non-Image Areas for ReductionIn Reduce mode, the change solenoid (SL1) turns on, and the lens moves accordingto the selected reproduction ratio. When the change solenoid (SL1) turns off, the drive ofthe lens motor is transmitted to gears A and B, thereby moving the slide shutter (rear,front) for the appropriate distance to open the exposure window. In this condition, thelight from the pre-exposure lamp is directed to the photosensitive drum by way of thereflecting plate for size blanking.Figure 4-1163. Blanking (Whiting) Out the Leading/Trailing Edges and between CopiesThe blank shutter solenoid drive signal (BSSSLD) turns on or off under the control ofthe microprocessor (Q301) on the DC controller. The leading/trailing edge and the areabetween copies are blacked (whited) out by opening the open/close shutter in this way.Figure 4-117COPYRIGHT © 1997 CANON INC. CANON NP6218 REV. 0 MAY 1997 PRINTED IN JAPAN (IMPRIME AU JAPON)CHAPTER 4 IMAGE FORMATION SYSTEM4-19A BSize blanking optical pathFull blanking optical pathOpen/close shutterSlide shutterPre-exposure optical pathDrum cartridgeDrum cleaningassemblyPre-exposurereflecting plateReflecting platefor size blankingReflecting platefor full blankingImage exposureoptical pathPhotosensitivedrum
