Vol. 36, issue 08, article # 8

Abstract:

A simplified mathematical model and the results of experimental studies on the spectral composition of radiation from a compact waveguide CO₂ laser with RF excitation for a laser opto-acoustic gas analyzer are presented. The aim is to improve measurement accuracy by eliminating unwanted 10R-branch lines from the laser spectrum. Laser radiation signatures are measured under various resonator and active medium parameters without the use of additional selection elements. It is demonstrated that optimal signatures can be achieved by selecting the appropriate pressure of the gas mixture, the transmittance coefficient of the output mirror, and the optimal resonator length, which can be obtained by varying the nominal (base) length within a range of 2 mm. The effectiveness of optimizing the spectral composition of laser radiation is practically confirmed by statistical results for 64 lasers. The open up new possibilities for improving the measurement accuracy of SF₆ laser opto-acoustic gas analyzers and extending its application in various fields of science and technology.

Keywords:

CO2 laser, stabilization, gas analysis, signature, wavelength selection, mid-infrared range

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