Brother International MFC-P2000 Service Manual - Page 38

2) Exposure Stage After the drum is positively charged, it is exposed to the light emitted from the laser unit. Drum Laser Beam Paper Laser detector Laser diode Lens Laser beam f
lens Polygon mirror Motor Fig. 2-27 The area exposed to the laser beam is the image to be printed. The surface potential of the exposed area is reduced, forming the electrostatic image to be printed. Surface Potential (V) +1150 +700 +400 Drum +300 Sleeve 1 Cycle of drum 1 2 34 (a) (b) 1 Primary charging 2 Laser beam exposure and developing (a) Unexposed area ( Non image area ) (b) Exposed area ( Image area ) 3 Transfer the image to paper 4 Erase the residual potential Time Fig. 2-28 II-19