Optical device for adjusting the spatial distribution of a laser beam. The device (1) comprises an assembly (2) of two matrices (3, 4) of lenses (5a), said matrices (3, 4) being identical and arranged parallel to one another with a uniform spacing between them, said assembly (2) being traversable by a laser beam (6), and controllable activating means (10) capable of modifying the spacing between the two matrices (3, 4) to create a zoom effect.
