7. Controlling the Activation in Hole Image Erase ModeIn hole image erase mode, images of such holes as punched in the original areerased by turning on LEDs to prevent adhesion of toner along the width.The width may be adjusted between 1 and 20 mm.Figure 4-1208. Controlling the Activation in AE ModeIn AE mode, the surface potential of the drum is measured so that the blankexposure LEDs would have to be turned off.Since only parts of the photosensitive drum are used to measure the surfacepotential, however, those LEDs that are over the area of measurement are turned withthe remaining LEDs kept on.Figure 4-121Photosensitive drumBlank exposure lamp (LEDs)Potential sensorFeedingdirection1 to 20 mmCOPYRIGHT © 1997 CANON INC. CANON NP6350/NP6251 REV. 0 JULY 1997 PRINTED IN JAPAN (IMPRIME AU JAPON)CHAPTER 4 IMAGE FORMATION SYSTEM4-21Download service manual and resetter printer at http://printer1.blogspot.com