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Applications which may make use of "narrow spectral" properties of diode lasers include range-finding, telecommunications, infra-red countermeasures, spectroscopic sensing, generation of radio-frequency or terahertz waves, atomic clock state preparation, quantum key cryptography, frequency doubling and conversion, water purification (in the UV), and photodynamic therapy (where a particular wavelength of light would cause a substance such as porphyrin to become chemically active as an anti-cancer agent only where the tissue is illuminated by light).

Applications where the desired quality of laser diodes is their ability to generate ultra-short pulses of light by the technique known as "mode-locking" include clock distribution for high-performance integrated circuits, high-peak-power sources for laser-induced breakdown spectroscopy sensing, arbitrary waveform generation for radio-frequency waves, photonic sampling for analog-to-digital conversion, and optical code-division-multiple-access systems for secure communication.

Common wavelengths

>INVISIBLE

• 375 nm - excitation of Hoechst stain, Calcium Blue, and other fluorescent dyes in fluorescence microscopy

• 405 nm - InGaN blue-violet laser, in Blu-ray Disc and HD DVD drives

>VISIBLE

• 473 nm - Bright blue laser pointers, still very expensive, output of DPSS systems

• 485 nm - excitation of GFP and other fluorescent dyes

• 532 nm - AlGaAs Bright green laser pointers, frequency doubled 1064 nm IR lasers (SHG)

• 593 nm - Yellow-Orange laser pointers, DPSS

• 635 nm - AlGaInP better red laser pointers, same power subjectively 5 times as bright as

670 nm one

• 640 nm -

• 650 nm - AlGaInP DVD drives, laser pointers

• 660 nm -

• 670 nm - AlGaInP cheap red laser pointers

•

>INVISIBLE

• 785 nm - GaAlAs Compact Disc drives

• 808 nm - GaAlAs pumps in DPSS Nd:YAG lasers (e.g. in green laser pointers or as arrays in higher-powered lasers)

• 848 nm - laser mice

• 980 nm - InGaAs pump for optical amplifiers, for Yb:YAG DPSS lasers

• 1064 nm - AlGaAs fiber-optic communication

• 1310 nm - InGaAsP fiber-optic communication

• 1480 nm - InGaAsP pump for optical amplifiers

• 1550 nm - InGaAsP fiber-optic communication

• 1625 nm - InGaAsP fiber-optic communication, service channel