DeepLightSeekdefinition:
A light source based on superluminescence.
Super radiation light source (also known asASELight source is a broadband light source (white light source) based on superluminescence. (It is often mistakenly referred to as a superluminescent light source, which is based on a different phenomenon called superfluorescence.) Generally speaking, a superluminescent light source contains a laser gain medium that radiates light after being excited and then amplifies it to emit light.
Super radiation light sources have very low temporal coherence due to their large radiation bandwidth (compared to lasers). Therefore, it greatly reduces the possibility of spot generation, which is often seen in laser beams. However, its spatial coherence is high, and the output light of the superluminescent light source can be well focused (similar to a laser beam), resulting in much higher light intensity than incandescent lamps. Therefore, this light source is highly suitable for optical coherence tomography（Optical Coherence Tomography, OCT）Device characteristic analysis (in fiber optic communication), gyroscope and fiber optic sensor. You can refer to the entry "Super Radiation Diode" for more detailed application information.
The most important type of superluminescent light source is the superluminescent diode（Superluminescent Diodes, SLDs）And fiber amplifiers. Fiber based light sources have higher output power, howeverSLDsIt has a smaller volume and lower cost. The radiation bandwidth of both is at least a few nanometers and tens of nanometers, sometimes even greater thanone hundrednanometer.
For all high gainASEFor light sources, careful suppression of optical feedback (such as reflections from fiber optic ports) is required, which can result in parasitic laser effects. For devices using optical fibers, the Rayleigh scattering inside the fiber will have an impact on the final performance indicators.
apictureone: Generated by fiber amplifiersASESpectrum, a curve calculated at different pump powers. As the power increases, the spectrum shifts towards shorter wavelengths (gain rapidly increases) and the spectral lines become narrower. Wavelength shift is normal for quasi three-level gain media, while spectral line narrowing occurs in almost all superluminescent sources.
