Source: Adopted From www.computerhope.com
Similar to a laser printer, LED printers are non-impact but use a light-emitting diode instead of a laser in the printhead. LED printers were originally developed by Casio and function by focusing light across the entire length of the drum, thus creating areas that are less charged, which attracts toner. The printer then transfers the toner from the drum to the paper and applies intense heat to fuse the toner to the paper.
There are many advantages to owning and LED printer vs. the conventional laser printer, including higher efficiency and reliability, due to their having fewer parts and no moving parts in the print head.
Also published on Medium.