A gold-palladium thin-film microsensor array for thermal imaging of laser beam waists

A new thermal microsensor, developed to control the position, focusing and 2D energy profile of laser beam waists is described. The sensitive area con sists of a planar array of 16 individual thin-film gold-palladium thermocou ple junctions (8 x 8 mu m(2)), processed by means of standard integrated ci rcuit technology (metallization on a glass substrate). The sensor thermoele ctric response is determined; especially, the dynamic behaviour is characte rized by measuring the time constant. Finally, thermal images and 2D beam e nergy profiles are obtained by scanning the sensor through Gaussian waists; a good agreement between the experimental results and the Gaussian beam th eory is observed. (C) 2000 Elsevier Science S.A. All rights reserved.