Thorlabs semiconductor lasers have use in remote sensing
The ULN15PT 1550 nm ultra-low-noise semiconductor laser provides output power >100 mW, linewidth <100 Hz, and relative intensity noise (RIN) <165 dB/Hz. Based on a fiber Bragg grating (FBG) external cavity design, they are designed for remote sensing, optical comb generation, and RF/microwave photonics.
Thorlabs
Newton, NJ