Utilizzo dei laser DFB per la rivelazione di ossigeno gassoso

A DFB laser has been used for the detection of gaseous oxygen inside food packaging. The technique that we have applied is the Tunable diode laser spectroscopy (TDLAS) with Wavelength modulation spectroscopy (WMS). We have abandoned the classical analogic lock-in configuration and we have implemented a WMS completely digital, called dWMS. To overcome noise in measurements due mostly to self-mixing of light back-scattered from surfaces, we have investigated some solutions, like differential measurements, mechanical vibration, averaging.