An LED printer is a type of computer printer similar to a

laser printer Laser printing is an electrostatic digital printing process. It produces high-quality text and graphics (and moderate-quality photographs) by repeatedly passing a laser beam back and forth over a negatively-charged cylinder called a "drum" t ...

. Such a printer uses a

light-emitting diode A light-emitting diode (LED) is a semiconductor device that emits light when current flows through it. Electrons in the semiconductor recombine with electron holes, releasing energy in the form of photons. The color of the light (c ...

(LED) array as a light source in the printhead instead of the laser used in laser printers and, more generally, in the

xerography Xerography is a dry photocopying technique. Originally called electrophotography, it was renamed xerography—from the roots el, ξηρός, label=none ''xeros'', meaning "dry" and -γραφία ''-graphia'', meaning "writing"—to emphasiz ...

process. The LED bar pulse-flashes across the entire page width and produces the image on the print drum or belt as it moves past.

LED A light-emitting diode (LED) is a semiconductor device that emits light when current flows through it. Electrons in the semiconductor recombine with electron holes, releasing energy in the form of photons. The color of the light ...

s are more efficient and reliable than conventional

s, since they have fewer

moving parts Machines include both fixed and moving parts. The moving parts have controlled and constrained motions. Moving parts are machine components excluding any moving fluids, such as fuel, coolant or hydraulic fluid. Moving parts also do not includ ...

, allowing for less mechanical wear. Depending on design, LED printers can have faster rates of print than some laser-based designs, and are generally cheaper to manufacture. In contrast to LED printers, laser printers require combinations of rotating mirrors and lenses that must remain in alignment throughout their use. The LED print head has no moving parts, and the individual assemblies tend to be more compact.

History

Oki Electric Industry , commonly referred to as OKI, OKI Electric or the OKI Group, is a Japanese information and communications technology company, headquartered in Toranomon, Minato-ku, Tokyo and operating in over 120 countries around the world. OKI produced the ...

claims to have made the first LED printer in 1981. A commercialized variant called OPP6220 was developed in 1986. It was a compact monotonic printer with a resolution of 240 dpi and a speed of 16 ppm. A 1989 model called OL400 was noted for its low cost. By 1997, Oki has pushed the resolution to 1200 dpi, and has produced upscaled models that handle A3-sized paper. The OKIPAGE 8c from 1998 was the first color LED printer for OKI. It simply utilizes a tandem array of four LED-toner pairs.

Variants

OKI Data has developed specialty LED Printers that use a CMYW toner system rather than

CMYK The CMYK color model (also known as process color, or four color) is a subtractive color model, based on the CMY color model, used in color printing, and is also used to describe the printing process itself. The abbreviation ''CMYK'' refers ...

. The OKI 920WT and 711WT have been developed for apparel-decorating processes, replacing the typical black toners ("K") with a white toner. The purpose is to allow the heat transfer application to dark fabrics and maintain the vibrancy of the colors. The LED immediately prints and dries the full color image onto a velum-like material, which is then heat-pressed to an adhesive sheet for application.

References

External links

* Computer printers Non-impact printing {{Comp-hardware-stub