Abstract: Device for sampling a plurality of parts of a light beam, comprised of at least one optical component which comprises a plate made of a material which is transparent to the light beam, where this plate has first and second faces which are flat and parallel, and a third face which is flat and which forms a dihedron with the first face, where the angle of this dihedron is equal to ?-? where 0<??Arcsin(1/n) where n if the refractive index of the material, so that by sending the light beam onto the first face, at an angle of incidence equal to Arcsin(n·sin(?)), a first sampled part (44) and a second sampled part are recovered, as well as the greater part of the light beam. The device is applicable in particular to the diagnostics of a laser beam.

Abstract: Optical system for processing a light beam comprises first and second optical means that are convergent and divergent respectively and form an afocal optical device. The first optical means comprises a single convergent lens. According to the invention, this convergent lens provides an order 0 beam and an order 2 beam resulting from the light beam to be processed passing through this lens after having been subjected to a 0 reflection and 2 reflections respectively on the lens faces, and the lens is optimised for the order 2 beam and has an aperture f/# less than 4 for this order 2 beam, with a wave front quality less than ? peak-to-valley, where ? is the wavelength of the light beam to be processed.

Abstract: Optical system for processing a light beam comprises first and second optical means that are convergent and divergent respectively and form an afocal optical device. The first optical means comprises a single convergent lens. According to the invention, this convergent lens provides an order 0 beam and an order 2 beam resulting from the light beam to be processed passing through this lens after having been subjected to a 0 reflection and 2 reflections respectively on the lens faces, and the lens is optimised for the order 2 beam and has an aperture f/# less than 4 for this order 2 beam, with a wave front quality less than ? peak-to-valley, where ? is the wavelength of the light beam to be processed.

Abstract: Device for sampling a plurality of parts of a light beam, comprised of at least one optical component which comprises a plate made of a material which is transparent to the light beam, where this plate has first and second faces which are flat and parallel, and a third face which is flat and which forms a dihedron with the first face, where the angle of this dihedron is equal to ?-? where 0<??Arcsin(1/n) where n if the refractive index of the material, so that by sending the light beam onto the first face, at an angle of incidence equal to Arcsin(n·sin(?)), a first sampled part (44) and a second sampled part are recovered, as well as the greater part of the light beam. The device is applicable in particular to the diagnostics of a laser beam.