laser diode


Also found in: Dictionary, Thesaurus, Medical, Acronyms, Wikipedia.

laser diode

[′lā·zər ¦dī‚ōd]

laser diode

A semiconductor-based laser used to generate analog signals or digital pulses for transmission through optical fibers. Both laser diodes and LEDs (light-emitting diodes) are used for this purpose, but the laser diode generates a smaller beam that is easier to couple with the smaller core of singlemode fibers. Laser diodes are designed to emit light either from their edge or their surface, the latter providing a circular beam that couples better with the round core of the fiber.

Laser diodes work on the same principle as the bigger gas lasers. They function as an optical oscillator by stimulating a chain reaction of photon emission inside a tiny chamber. In edge-emitting lasers, the semiconductor waver is cleaved, and the inherent properties of the semiconductor create reflective ends that may or may not be enhanced with additional reflective films. With vertical cavity surface emitting lasers (VCSELs), the reflectivity has to be added.

The most common semiconductors used in laser diodes are compounds based on gallium arsenide (750 to 900 nm in the infrared), indium gallium arsenide phosphide (1200 to 1700 nm in the infrared) and gallium nitride (near 400 nm in the blue). See laser and solid state laser.


Laser Diodes
Laser diodes such as these are all fabricated using semiconductor processes just like CPU and memory chips. Note that the VCSELs (vixels) produce a circular beam that couples well with a fiber.







A Tunable Laser Diode
Laser diodes also make great sensors. This laser diode from Jet Propulsion Labs is tunable to different frequencies in order to detect various gases both on this and other planets. (Image courtesy of JPL's Microdevices Laboratory; Robert M. Brown, photographer)
References in periodicals archive ?
Favoring mass storage at superior formats, Blu-ray and high density digital versatile disk (HD DVD) technologies are expected to drive the 405 nm laser diodes in an appreciable manner, triggering product developments and performance enhancements in the blue-violet laser diode market.
Photonic Products is an ISO9001:2000 certified manufacturer of custom designed laser diode modules and an authorized distributor of high performance industrial laser diodes manufactured by Sanyo, Opnext (formerly Hitachi) and Sony, LEDs, and precision optical lenses.
Red and blue laser diodes have been commercially available among the primary red-green-blue (RGB) colors,but there has been greater need for high output green laser diodes towards the development of high performance laser projectors and display devices.
At the speed at which the industry is moving, I wouldn't be surprised if in four to five years, when you go to Best Buy to buy cables for all your electronics, you'll be selecting cables with laser diodes embedded in them," Deppe said.
By exploring the geographical and temporal transfer of laser diode fabrication technology, we investigate how this scientific knowledge made the transition from the United States to Japan, where it flourished in mass market applications.
A DVD-ROM pickup unit requires two laser diodes, one for DVD and another for CD since reading CD-R media is a requirement for a combo drive.
Last year, a team of Japanese researchers announced that it had developed gallium nitride (GaN) semiconductor laser diodes that provide a continuous output of blue light at room temperature.
Because of the small core diameters of single-mode fibers, a laser diode (LD) rather than a light emitting diode (LED) is preferred as a light source.
This represents the world's first desktop projector demonstration based on high power nonpolar-semipolar laser diode technology.
Tenders are invited for UCB - AR Coated Laser Diode -1 each Antireflection (AR)-coated Laser Diode suitable for injection-locking at 461nm.
com)-- The Optoelectronics Company is delighted to announce that Oclaro's high power HL63193MG laser diode is now in mass production, news which will interest the laser TV, video projection and show laser markets, desperate as they are for higher and higher power output from ever smaller laser diode packages.

Full browser ?