High power DFB laser diodes for gas sensing in rough environments

摘要

Recent years have seen a considerable increase of laser based gas and liquid sensing including fields of application in medical analytics, environmental monitoring or process control.rnThe significant success of tunable laser diode spectroscopy (TDLS) in these areas is based particularly on its sophisticated detection limits in the range of ppm to ppb. Suitable lasers are an essential prerequisite of this technological approach. Typical devices for example used for H_2O or OH sensing operate at emission wavelengths in the 2.6 - 2.7 μm range due to the very intense absorption features of both water and hydroxide in this wavelength range. Such laser diodes have typical output power levels of 1-3 mW.