ONERA (Office National d’Etudes et de Recherches Aérospatiales) is a public, scientific and technical establishment with both industrial and commercial responsibilities, ONERA reports to the French Ministry of Defence and enjoys financial independence. The expertise of ONERA covers all the scientific disciplines involved in aircraft, spacecraft and missile design. The activities of Fundamental and Applied Energetics Department (DEFA) are focused on the operation of propulsion system for aircraft, helicopters, missiles and launch vehicles. A large place is given to the study of internal reactive flows of air breathing propulsion. The activity of the Physics, Instrumentation and Sensing Department (DMPH) is dedicated to the development of instruments and measurements in fields such as combustion, hypersonic flow fields etc.. In the field of the Low Emission Combustion DMPH has a great expertise obtained in the different European programs TLC, MUSCLES, and NEWAC. All these developments required the use of quantitative laser-based diagnostics for measurements of species concentrations and temperature in combustors operating at realistic conditions representative of aircraft engines.