Refilling the cartridge
In most laser printers, the cartridges contain a large empty space containing a very fine dry powder called toner. The toner is passed on to other components, which eventually melt the toner onto the paper to be printed. Printers have different ways of detecting when the toner runs out. Some Brother printers let light pass through the cartridge, and a large amount of light passing through indicates that there is little toner left. They... Read More "Refilling the cartridge