A distributed-feedback laser (DFB) is a type of laser diode, quantum-cascade laser or optical-fiber laser where the active region of the device contains a periodically structured element or diffraction grating. Typically, the periodic structure is made with a phase shift in its middle. The acronym DFB laser stands for distributed feedback laser. It's important to note that the wavelength tunability. The DFB1550P laser diode is available as a turnkey laser system (Item # DFB15TK). Please see our Low-Noise, Narrow-Linewidth Laser Systems for more. They are used for high-performance gas sensing applying tunable diode laser spectroscopy. nanoplus lasers operate reliably in more than 100,000 installations worldwide. Applications include power plants, gas pipelines and emission control systems as well as airborne and satellite applications.