L band (infrared)
L-band is a name used for a fixed range of infrared frequencies. The definition of the range depends on the application, with different bands used for fibre-optic communications and astronomy.
Fibre-optic telecommunications

In infrared optical communications, L-band refers to the wavelength range 1565–1625 nm.[1] The L-band is located next to the conventional (C) band (1530–1565 nm).
Infrared astronomy

In infrared astronomy, the L band is an atmospheric transmission window centred on 3.5 micrometres (in the mid-infrared).
References
- ↑ Optical Fiber Communications article in rp-photonics' Encyclopedia of Laser Physics and Technology (accessed Nov. 11 2010)
