4/21 Laser Printers. Roll call Video Lecture: –laser printers

Laser Printers: parts. Paper feeder rollers Laser Mirrors Toner cartridge Drum Corona wire Fusing rollers Paper feeder rollers Laser Mirrors Toner cartridge Drum Corona wire Fusing rollers Paper feeder rollers Laser Mirrors Toner cartridge Drum Corona wire Fusing rollers Paper feeder rollers Laser Mirrors Toner cartridge Drum Corona wire Fusing rollers Paper feeder rollers Laser Mirrors Toner cartridge Drum Corona wire Fusing rollers Paper feeder rollers Laser Mirrors Toner cartridge Drum Corona wire Fusing rollers Paper feeder rollers Laser Mirrors Toner cartridge Drum Corona wire Fusing rollers Paper feeder rollers Laser Mirrors Toner cartridge Drum Corona wire Fusing rollers

How it works: 1. Laser gets info. The computer sends data to the printer that tells where black areas are on the paper. The laser converts the data into pulses of light to beam at the drum.

2. The laser passes it on. The information is set up in a grid of black areas and white areas. The laser beams, horizontal line by horizontal line, this grid of dark areas.

3. The drum receives it. When the drum is hit with the laser beam, it electrically charges the coating at that spot. In HP & Canon printers, the coating is positively charged.

4. The drum rolls past the toner bin. As the drum rolls by, the positively charged parts of the coating on the drum attract the toner particles. Meanwhile, back at the ranch...

5. The paper rolls in. The sheet of paper that is coming along the paper train is also positively charged with electricity. This charge is stronger than the drums charge.

6. The paper lures the toner. The sheet of paper touches the drum coated in toner. The toner jumps to the paper from the drum because of the stronger charge on the paper.

7. The Fusing Rollers. The paper, with the toner particles, goes to the fusing rollers. The rollers use pressure and heat to bind the toner to the paper permanently. Meanwhile, back at the ranch...

8. The Corona Wire Cleans Up. The drum rolls past the corona wire, which restores the coating to its original state: uniformly, negatively charged. The corona wire does this by using a stronger positive charge to wipe the drum clean.

9. Ready to do it again? The printer is now ready for the next sheet of paper.