What technology does the laser printer use to print document?

Most consumer inkjet printers, from companies including Canon, Hewlett-Packard, and Lexmark (but not Epson), use print cartridges with a series of tiny chambers each containing a heater, all of which are constructed by photolithography. To eject a droplet from each chamber, a pulse of current is passed through the heating element causing a rapid vaporisation of the ink in the chamber to form a bubble, which causes a large pressure increase, propelling a droplet of ink onto the paper (hence Canon's tradename of Bubble Jet for its technology). The ink's surface tension, as well as the condensation and thus contraction of the vapor bubble, pulls a further charge of ink into the chamber through a narrow channel attached to an ink reservoir.

Laserjet printers employ a xerographic printing process (i.e. electrical transfer of an image's negative) but differ from analog photocopiers in that the image is produced by the direct scanning of a laser beam across the printer's photoreceptor. In total, there are six steps to the printing process: cleaning, charging, writing (or exposing), developing, transferring, and fusing.