Frequently Asked Questions

The FBG acts as an external reflector placed close to the laser diode. By reflecting a narrow slice of the diode's emission back into the cavity at a precisely defined wavelength, it locks the laser's output wavelength instead of letting it drift with temperature or current.

Low-reflectivity gratings (2–5%, FWHM 0.3–0.8 nm) are ideal for pump-diode power stabilization. Higher-reflectivity gratings (10–20%, FWHM around 0.1 nm) placed close to the laser chip are used to create single-frequency sources.

FORC-Photonics offers wavelength-locker FBGs with positioning accuracy up to ±0.02 nm.