laser printer \laser printer\ n.
   A printer controlled by a computer, using a laser beam to
   produce images in a fine dot-matrix pattern of charge on an
   electrostatic drum, to which fine particles of ink are
   subsequently caused to adhere, and the image of which is
   subsequently transferred to paper or another type of material
   in sheet form. It is capable of high-speed production of
   images with a higher resolution than those from dot-matrix
   impact printers.
   [PJC]

	

	laser printer
    n 1: electrostatic printer that focuses a laser beam to form
         images that are transferred to paper electrostatically

	

	laser printer

    A non-impact high-resolution printer which uses a
   rotating disk to reflect laser beams to form an electrostatic
   image on a selenium imaging drum.  The developer drum
   transfers toner from the toner bin to the charged areas of the
   imaging drum, which then transfers it onto the paper into
   which it is fused by heat.  Toner is dry ink powder, generally
   a plastic heat-sensitive polymer.

   Print resolution currently (2001) ranges between 300 and 2400
   dots per inch (DPI).  Laser printers using chemical
   photoreproduction techniques can produce resolutions of up to
   2400 DPI.

   Print speed is limited by whichever is slower - the printer
   hardware (the "engine speed"), or the software rendering
   process that converts the data to be printed into a bit map.

   The print speed may exceed 21,000 lines per minute, though
   printing speed is more often given in pages per minute.  If a
   laser printer is rated at 12 pages per minute (PPM), this
   figure would be true only if the printer is printing the same
   data on each of the twelve pages, so that the bit map is
   identical.  This speed however, is rarely reached if each page
   contains different codes, text, and graphics.

   In 2001, Xerox's Phaser 1235 and 2135 (with Okidata engines)
   could print up to 21 colour ppm at 1200x1200 DPI using a
   single-pass process.

   Colour laser printers can reach 2400 DPI easily (e.g. an HP
   LaserJet 8550).  Some printers with large amounts of RAM can
   print at engine speed with different text pages and some of
   the larger lasers intended for graphics design work can print
   graphics at full engine speed.

   Although there are dozens of retail brands of laser printers,
   only a few original equipment manufacturers make print
   engines, e.g. Canon, Ricoh, Toshiba, and Xerox.

   (2002-01-06)