Micronic intensity analysis and imaging in laser optics by means of micro-thermoelectrical sensors

This work deals with the use of ultra-thin thermoelectric couples as a mean for illumination control and investigation in the field of laser optics. After the description of the different sensors and their main characteristics, their different uses for measurement and imaging of laser beams or laser sheets profiles are presented, the spatial and temporal qualities of such sensors allowing the localized detection of light power densities. A more specific and versatile sensor is then proposed to be used in the field of laser Doppler velocimetry where special needs have appeared. Besides, the positioning and energy analysis of the measurement volume, this probe allows the precise determination of the fringes spacing under real conditions, this parameter governing the precision of the velocity measurement. Finally, such thermoelectric sensors appear to be an interesting alternative to the previous techniques of positioning and analysis of coherent light distributions because of a low cost, and a simple carrying out.