In case you’re wondering why I refer to certain types of laser-like printers as “laser-class” devices, rather than simply laser printers, there’s a sound technical reason, I assure you. “True” laser printers use a laser mechanism inside to draw the page image to be printed onto the printer’s drum (which then picks up and transfers toner to the page). This is quite similar to what LED printers do, but they don’t do it with lasers.
LED-based machines, on the other hand, charge the page image onto the print drum with an array of light-emitting diodes. (Mind you, this isn’t a ploy by manufacturers to make knock-off laser printers; substituting LEDs for lasers simply allows printer manufacturers to make smaller and lighter printers with fewer moving parts.) All else being equal, LED models tend to cost less to manufacture than do their laser counterparts. Aside from the economics involved, though, LED-based printers function much the same as laser devices do, and they act identically from the outside; hence, I call them “laser-class” printers—though there is nothingÂ laserÂ about them.
Read the entire article at About.com.