Specifications

Figure 4 Laser printing produces an attractive “embossed” appearance because the toner is fused to the
surface of the paper. Extremely rough paper can cause imaging problems, although laser printers can handle
many more types of paper than inkjet printers can.
LED Page Printers
LED page printers, pioneered by Okidata and produced by Okidata and Lexmark, represent an excel-
lent alternative to a “true” laser printer. Both technologies use a rotating drum and copier-like fusing
mechanism to create high-quality printing. The difference is that LED page printers use an LED (light-
emitting diode) array, rather than a laser beam, to place the image data on the imaging drum (see
Figure 5). This difference in imaging provides three advantages:
■ A straight-through paper path
■ A longer warranty on the print head compared to laser printers
■ Faster color printing because all colors can be placed in a single pass, compared to the four-pass
method that must be used by color laser printers (one color per pass)
Upper Teflon Roller
Heater Halogen
Toner applied in
powder form
Lower Pressure Roller
Dear Sir:
Focusing lens
Toner
Rotating
drum
LED array
Figure 5 LED printers use a light-emitting diode array to place the image on the imaging drum.
From the standpoint of print quality and speed, LED page printers produce quality comparable to
similar laser printers. In essence, LED page printers are “laserless laser printers.”
Note
Whether you print black or white text or graphics with a typical LED page or laser printer, similarly rated printers produce
an identical page at about the same time. The same is not true for color, however. Why?