CHAPTER 4 IMAGE FORMATION SYSTEMCOPYRIGHT © 1999 CANON INC. CANON NP6320 REV.0 DEC. 1999 PRINTED IN JAPAN (IMPRIME AU JAPON)4-2B. Basic Operation of Image Formation SystemFigure 4-102ONWMUPRWMUPCopy Start keySCRV SCRVSTBY INTR SCFW SCFWAERLSTR STBYMain motor (M1)/pre-exposure lampScanner movementScanner home positionsensor (Q3) signalScanning lamp (LA1)Primary/transfercorona assemblyForwardGrid bias ON/OFFDeveloping bias DCcomponentDeveloping bias ACcomponentBackward