Alignment of multistate laser amplifiers with periodic space filtration of beam

Multistage laser amplifiers with periodic space filtration of the beam, used for many applications as diverse as nonliner spectroscopy and X-ray lithography, contain many optical components which must be aligned for optimum or even adequate performance. Except for computer-aided automatic alignment of parallel channels, most alignment is done manually, either directly or from a remote control panel. Alignment is complete when the apertures of all successive optical components have been centered within required accuracy in the direction of the laser beam. For this, along with the beam from the driving pulse source, there is also passed through the amplifier channel a continuous beam from an aligning laser with the same space structure and wavelength. The basic procedure is demonstrated on a single-channel amplifier with a Nd3+ glass laser and several successive stages of planar optics, each preceded by a space filter, with an eyepiece behind the last stage.