Method and apparatus for temporal and spatial beam integration

Abstract

A method and apparatus for providing sequential temporal and spatial integration of a collimated non-symmetrical excimer laser beam to optimize the temporal and spatial characteristics of the beam. The temporal integrator comprises a pair of cylindrical lenses spaced along the beam axis by a distance substantially equal to the sum of the focal length of both lenses, and a motor mechanism for rotating the two spaced cylindrical lenses about the beam axis. The spatial beam integrator includes a plurality of prisms distributed about a hollow center, the outlet face of each prism being angled with respect to the body axis of the spatial beam integrator so that portions of the laser beam passing through a given prism are refracted towards the center upon emergence from the outlet face. The spatial beam integrator is preferably rotated about the beam axis at twice the rotation rate of the cylindrical lenses so that the rotated beam emerging from the temporal beam integrator is stationary with respect to the spatial beam integrator. Alternatively, the spatial beam integrator may be rotated at the same rate as the cylindrical lenses, or may be maintained stationary, i.e., not rotated at all.

Dependencies are inferred from the claim text.