laser diode

(redirected from Laser diodes)
Also found in: Dictionary.
Related to Laser diodes: CW laser, Semiconductor lasers

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 ?
Significant increase in the use of laser diodes in several end-use markets due to a number of valuable features provided by this technology compared to traditional technology is a chief factor driving the global market.
m distributed feedback (DFB) laser diodes for 100Gbit/s transceivers, the company said.
Oclaro's high performance laser diodes are proven to consume a low operating current which extends battery life whilst maintaining the integrity of the laser diode power in a variety of applications such as inspection, measurement and biomedical applications and as a light source for optical equipment.
Handbook of Distributed Feedback Laser Diodes appears in its second updated edition - the first since 1997 - to cover the many changes in the industry and the changed role of DFB laser diodes.
This cross-licensing agreement grants each party the right to use inventions related to LED and laser diodes covered by the patents owned by the respective companies around the world.
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.
The new laser diodes represent a sharp departure from past commercial devices in how they are made," Deppe said.
The first laser diodes were developed simultaneously by four American institutions working independently--General Electric (GE), International Business Machines (IBM), the University of Illinois Urbana-Champaign (UIUC), and the Massachusetts Institute of Technology (MIT) in 1962.
The receptacle packaged laser diodes, with wavelengths from 635 nm to telecomms wavelengths of 1310-1550 nm and optical output powers from 0.
The OZII with Laser Diodes eliminates spherical distortion, pin cushioning or barrel distortion.
Tunable laser diodes and related optical sources, 2d ed.
said Wednesday they have agreed to cooperate to develop mass production-level blue-violet laser diodes used in rewritable optical memory disks by the spring of 2003.

Full browser ?