Investigation of laser‐induced grating spectroscopy of O ₂ for accurate temperature measurements towards applications in harsh environments

We present an in-depth investigation of laser-induced grating spectroscopy (LIGS) for temperature measurements in practical applications using a narrow-band dye laser with 760 nm wavelength and pulse duration 8 ns as the source pump beams creating grating. The was set to be either resonant transition from band O2 generation thermal LIGS or nonresonant purely electrostrictive LIGS. Signals were generated ambient air well high-pressure high-temperature dry mixtures. Pump irradiances up 11 GW/cm2 used, which resulted strong contribution overall signals at atmospheric pressure, low due weak absorption by singlet . advantage disadvantage are discussed, potential environments. Furthermore, precision measurement is discussed comparing different analysis methods.