Patent ID: 8833945
Filing Date: 2014-09-16
Classification: G02B,G02F

Abstract:
1. A speckle reduction device for a coherent light beam comprising: an optical element configured to be passed through by the coherent light beam to be treated, characterised by: for speckle reduction of the coherent light beam; a heating means configured to heat said optical element; a cooling element coupled to said optical element in a manner effective to cool the optical element; and a control module configured to control the heating means and the cooling element in a manner effective to create random or pseudo-random thermal perturbations in the optical element, thereby causing corresponding variations in the refractive index of the said optical element, wherein said optical element is a piezoelectric crystal, and the heating means comprise electrodes applied to the crystal and connected to the control module to excite a vibratory mode of the crystal causing its heating.