Editing Laser diode (section)

=== Telecommunications, scanning, and spectrometry ===
Laser diodes are widely used in [[telecommunications]] as easily modulated and easily coupled light sources for [[optical fiber|fiber-optic]] communication. They are used in various measuring instruments, such as [[rangefinding telemeter|rangefinders]]. Another common use is in [[barcode reader]]s. [[visible spectrum|Visible]] lasers, typically [[red]] but later also [[green]], are common as [[laser pointer]]s. 

Both low- and high-power diodes are used extensively in the printing industry, both as light sources for scanning (input) of images and for very-high-speed and high-resolution printing plate (output) manufacturing. 

[[Infrared]] and red laser diodes are common in [[compact disc player|CD players]], [[CD-ROM]]s, and [[DVD]] technology. [[violet (color)|Violet]] lasers are used in [[HD DVD]] and [[Blu-ray Disc|Blu-ray]] technology. Diode lasers have also found many applications in [[laser absorption spectrometry]] (LAS) for high-speed, low-cost assessment or monitoring of the concentration of various species in gas phase. 

High-power laser diodes are used in industrial applications such as heat treating, cladding, seam welding, and for pumping other lasers, such as [[diode-pumped solid-state laser]]s.

Uses of laser diodes can be categorized in various ways. Most applications could be served by larger solid-state lasers or optical parametric oscillators, but the low cost of mass-produced diode lasers makes them essential for mass-market applications. Diode lasers can be used in a great many fields; since light has many different properties (power, wavelength, spectral and beam quality, polarization, etc.), it is useful to classify applications by these basic properties.

Many applications of diode lasers primarily make use of the ''directed energy'' property of the optical beam. In this category, one might include

* [[laser printer]]s
* [[Barcode reader|barcode readers]]
* [[image scanning]]
* illuminators
* designators
* [[Optical disc|optical data recording]]
* [[laser ignition|combustion ignition]]
* [[laser surgery]] - laser used to cut the tissue
* industrial [optical] sorting
* industrial machining
* [[wireless power transfer]], as power beaming
* [[directed energy weaponry]]

Some of the above applications are well-established, while others are emerging.