CHAPTER 3 EXPOSURE SYSTEMCOPYRIGHT © 1999 CANON INC. CANON NP6512/6612/7120/7130/7130F REV.0 AUG. 1999 PRINTED IN JAPAN (IMPRIME AU JAPON) 3-3Figure 3-103Lens home positionsensor (PS2)Lens shift detecting shaftfor side blanking lampLens unitReductionScanner/lens drive motor(M2)No. 4/5 mirror unitTop ViewSwitching gearWhile the lens is movingLens home position detectionsignal(LHP)Lens solenoid drive signal(LNSLD*)SL3DC controller PCBSL3 SL3ON OFFSwitchinggearSwitchinggearEnlargementCamLens cableWhile the scanner is movingC. Lens Drive System1. OutlineThe lens drive system is driven by the scanner/lens drive motor (M2). When the lens solenoid(SL3) turns on, the switching gear is pushed in the direction of . In this condition, when thescanner/lens drive motor rotates in reverse direction ( ), the lens unit will move in the direction ofreduction ( ) by the work of the gear and the lens cable.At the same time, the No. 4/5 mirror unit operates according to the distance over which the lensunit is moved by the work of the gear and the cam, thereby varying the optical length.At this time, the blanking lamp also moves in conjunction with the lens to blank out the appro-priate front/rear widths to suit the selected reduction ratio.
