Operation of a laser printer.

A page description language communicates the image to be printed. The first thing the printer does, is convert the instructions into a bitmap, which is done by its internal processor. An image (in memory), is the result, of which every dot will be placed on the paper. Models designated to be "Windows printers" don't have their own processors. Because of this, the host PC creates bitmap, which writes it directly to the printer's memory. In …

…In the first one, the toner, which was not transferred to the paper, is mechanically scraped off the drum and the waste toner is collected in a bin. Electrical cleaning takes the form of covering the drum with an even electrical charge so the laser can write on it again. This is done by corona wire, an electrical element. The felt pad, which cleans the drum, and the corona wire need to be changed regularly.