Differential absorption measurement by use of self-seeded gain-switched Fabry-Perot laser diode

Abstract
Differential absorption measurement for acetylene has been carried out by the use of a self-seeded, gain-switched Fabry-Perot (FP) laser diode. During the measurement, the two wavelengths from the laser output can be conveniently selected by switching the repetition frequency. The system has flexible wavelength tunability, larger sensitivity than those based on DFBs, and high potential for multi-point, multiple gas sensing.