Comptia A+ 220-701 Laser Printers

Photosensitive Drum

aka Image Drum. aluminum cylinder.

Hopper (Laser printers)

the reservoir where toner is stored

Finishers (Laser printer)

Add collating, stapling and binding functions.

Memory overflow errors, the solution (Laser printer)

Add more RAM.

Power supplies (Laser printers)

All laser printers have 2 power supplies. One is the primary power supply, the other is the high voltage power supply which powers only the primary corona, very dangerous, always unplug before opening the printer for anything but a cartridge change.

Duplexer (Laser printer)

Devices that allow you to print on both sides of the paper. If your printer doesn't have one, you can usually purchase one as an add-on component.

Laser printer

Type of nonimpact page printer that quickly produces quality text and images using powdered ink.

Step 2 in Laser Printing Process

(Charge) The primary corona wire applies a uniform negative charge to the entire surface of the drum, normally between 600 and 1000 volts.

Step 1 in Laser Printing Process

(Clean) A rubber head cleans loose particles off the photosensitive drum and the erase lamp gives the drum a totally neutral charge.

Step 4 in Laser Printing Process

(Develop) The negatively charged toner particles now stick to the positively charged spots making up the image on the drum.

Step 6 in Laser Printing Process

(Fuse)- The toner is physically attached to the paper by the Fuser, which contains a heat roller and a pressure roller. The paper is done.

Step 5 in Laser Printing Process

(Transfer) To transfer the image from the drum onto the paper, the transfer corona wire charges the paper with a positive charge. Once in proximity to this positive charge, the negatively charged toner particles leap from the drum to the paper. Then the static charge eliminator removes the paper's positive charge, leaving the particles resting on the paper, and the paper won't wrap around the drum since it is now neutral.

Step 3 in Laser Printing Process

(Write) The laser beam writes a positively charged image on the surface of the drum.

Toner cylinder (Laser printer)

Charges the ink particles negative so they stick to the positively charged drum.

Electrophotographic Laser Printing process

Clean, Charge, Write, Develop, Transfer, Fuse (Mnemonic: Clean Computers Will Develop True Friends) The process cycles once for each color. Laser printers have more than one drum to do a color picture etc.

Ozone Filter (Laser printer)

The amount of ozone generated by the coronas isn't harmful to humans, but it can damage printers at high levels. Replace periodically.

Toner (Laser printer)

The negatively charged ink is made to jump around from the drum image onto the paper (Both positively charged).

Toner Cartridge Components (Laser printers)

These are high-maintenance parts that are often included on the cartridge itself, so a replacement will replace the component too. Often it is the image drum, fuser assembly and ozone filter.