How Does A Printer Drum Work?
What Is A Printer Drum?
Well first maybe we better explain what a printer drum is. If you own a Brother laser printer you probably are used to having to change the Brother Printer Drum every few toner changes. Laser printers image paper by using a “drum.” This printer technology is very similar to technology used by photocopiers. Laser printers and copy machines use specially coated printer drums in order to create an image and transfer that image on to a sheet of paper.
Initially, the printer drum is given a total positive charge by the charge corona wire, a wire with an electrical current running through it. (Some printers use a charged roller instead of a corona wire, but the principle is the same.) As the printer drum revolves, the printer shines a tiny laser beam across the surface to discharge certain points. In this way, the laser “draws” the letters and images to be printed as a pattern of electrical charges — an electrostatic image. The system can also work with the charges reversed — that is, a positive electrostatic image on a negative background.
The laser “writes” on a photoconductive revolving print drum. After the pattern is set, the printer coats the printer drum with positively charged toner – a fine, black powder. Since it has a positive charge, the printer toner clings to the negative discharged areas of the printer drum, but not to the positively charged “background.” This is something like writing on a soda can with glue and then rolling it over some flour: The flour only sticks to the glue-coated part of the can, so you end up with a message written in powder. Read More: How Does A Printer Drum Work
