Abstract: Method for shielding a high-power laser apparatus (S) in which a laser beam is generated and then amplified in at least a first amplification stage, including spatial filtering (4) of the amplified laser beam, phase correction (3) carried out on the laser beam before it is spatially filtered, and a measurement of the aberrations (7) on the laser beam. The phase of the beam is corrected so as to produce a beam having minimal aberrations after spatial filtering. The shielding device (D, D?) implementing this method may in particular be employed in apparatus using an intense laser beam of high (terawatt) peak power and in proton therapy units.

Abstract: A device for amplifying high-energy ultrashort light pulses, includes a generator (1), a first amplifying/time-stretching element (2) including a time-stretching element (3), a regenerative amplifier (4), a multipass amplifier (5) and a compressor (6). The device further includes a second amplifying/time-stretching element (11), arranged at the output of the generator (1), amplifying and time-stretching the initial light pulses (7) to generate amplified and time-stretched pulses (13), and a filtering element (12) arranged between the second amplifying/time-stretching element (11) and the amplification unit (2), blocking the low-amplitude light signals (14) of the amplified and time-stretched pulses (13).

Abstract: Method for shielding a high-power laser apparatus (S) in which a laser beam is generated and then amplified in at least a first amplification stage, including spatial filtering (4) of the amplified laser beam, phase correction (3) carried out on the laser beam before it is spatially filtered, and a measurement of the aberrations (7) on the laser beam. The phase of the beam is corrected so as to produce a beam having minimal aberrations after spatial filtering. The shielding device (D, D?) implementing this method may in particular be employed in apparatus using an intense laser beam of high (terawatt) peak power and in proton therapy units.

Abstract: A device for amplifying high-energy ultrashort light pulses, includes a generator (1), a first amplifying/time-stretching element (2) including a time-stretching element (3), a regenerative amplifier (4), a multipass amplifier (5) and a compressor (6). The device further includes a second amplifying/time-stretching element (11), arranged at the output of the generator (1), amplifying and time-stretching the initial light pulses (7) to generate amplified and time-stretched pulses (13), and a filtering element (12) arranged between the second amplifying/time-stretching element (11) and the amplification unit (2), blocking the low-amplitude light signals (14) of the amplified and time-stretched pulses (13).

Abstract: A power cable joint device includes at least one tubular rigid support element, a cold-shrinkable, pre-expanded sleeve, and a releasable means for immobilizing the at least one support element with respect to the pre-expanded sleeve. Most of an exterior surface of the at least one support element is lubricated by a grease that does not flow under action of a pressure exerted by the pre-expanded sleeve. The pre-expanded sleeve grips the at least one support element over most of a length of the at least one support element. The pre-expanded sleeve also grips the at least one support element at internal ends of the at least one support element. The grease is based on a silicone or on a polyalkylene glycol and includes a filler, a pressure-withstanding additive, or both the filler and the pressure-withstanding additive.