METHOD FOR CONTROLLING THE SIZE AND SPATIAL PROFILE OF THE LASER SPOT IN THE TARGET PLANE

摘要

The invention relates to a method for controlling the size and spatial profile of the testing laser spot in automatic stations which measure the destruction threshold of optical components irradiated with laser nanosecond pulses. The claimed method uses an optical device with fixed working distance in order to adjust the size and shape of the spatial profile of a laser spot in the target plane and in order to obtain a smooth spatial profile of said spot and consists in carrying on several stages, starting with delivering a laser beam () by a laser source (), controlling the access of the laser beam () to a variable attenuator (), by means of a beam obturator (), where said attenuator sets the energy of laser pulses, after which the beam () is directed and centered on the optical axis of an optical device () by using two mirrors (), said stage being followed by the positioning, transverse to the propagation direction of the beam (), of a sample () whose surface () is to be tested and then adjusting the size and shape of the spatial profile in the plane of the surface-target (), by rotating a graduated adjustment ring of the optical device ().