Abstract: A portable system for the real time detection and measurement of one or several gases is a gaseous mixture is disclosed. Such systems can be applied to industrial domains in which gases are to be measured and particularly toxic, dangerous, or polluting gases are generated. The system uses absorption spectrometry of a gas from a gaseous medium of interest. The optical means is at least two laser diodes with matchable cavities to generate a first and second wavelength, a light beam mixer prism, a double refraction crystal rotating on a controlled table. The tuned beam causes the gas to be measured to fluoresce and emit a signal to an infrared radiation detector which can indicate the identity and magnitude of the gas being measured.