The laser cartridge contains two sections - the imaging section and developing section. The imaging section includes the photosensitive drum, wiper blade, recovery blade, primary charge roller, and waste toner hopper. The developing section contains the magnetic roller, doctor blade, toner agitator bar, toner supply hopper, and electrical contacts. Toner is applied to the drum using a negative charge from the primary charge roller and the magnetic roller. The doctor blade regulates the thickness of toner on the magnetic roller. The image is then transferred to paper using a positive charge from the transfer roller.

1. OPC
“Drum”
Toner
Supply
HopperLaser Beam
Agitator
Doctor
Blade
Magnetic Roller
Sleeve
PCR
Waste
Toner
Hopper
Heating
Element
Recovery
Blade
Wiper
Blade
Paper
Stationary Magnet
Upper and Lower
Fuser Rollers
Static charge
Eliminator
Transfer
Charge
Roller
Direction
Imaging
Section
Developing
Section
The Laser cartridge is a two part shell; Imaging Section (Waste Toner Hopper) and the
Developing Section (Toner Supply Hopper).
The Imaging Section has : Photosensitive Drum, Wiper Blade, Recovery Blade
Primary Charge Roller, Waste Toner Hopper & Electrical
Contacts
The Developing Section has : Magnetic Roller, Doctor Blade, Toner Agitator Bar,
Low Toner Bar (some), Toner Supply Hopper & Electrical
Contacts
A negative charge is applied to the O.P.C. by the P.C.R. Laser then writes to O.P.C. leaving a
positive image. Negative toner from MRS is attracted to the positive image on the drum.
The thickness of toner on M.R.S. is controlled by the doctor blade. Paper passes under the
O.P.C. with a positive charge from transfer roller. The image from the O.C.P. jumps from the
page, then passes across a fuser/static charge eliminator baking the image on the page as it
removes the positive charge.
About 95% of the toner is transferred to the page and the remaining toner on the O.C.P. is
removed by the wiper blade, caught by the recovery blade then falls into the waste toner
hopper. This leaves the O.P.C clean and ready to take the next image.
Basic Laser Cartridge