Patent ID: 7085053
Filing Date: 2006-08-01
Classification: G02B

Abstract:
1. A device for shaping the cross section of a light beam, comprising at least one beam shaping unit with beam splitter means, beam deflection means and beam combining means, the beam splitter means being able to divide the light beam which is incident on the beam shaping unit into two component beams, the beam deflection means being able to deflect at least one of the component beams onto the beam combining means, and the beam combining means being able to combine the two component beams, such that the cross section of the light beam emerging from the beam shaping unit compared to the light beam entering the beam shaping unit is reduced in at least one direction (X), wherein the beam combining means is made as a polarization-selective beam splitter and beam combination unit which comprises at least two parts with a boundary surface which is located between them, and the two separated component beams are incident on the boundary surface from different directions, and depending on their linear polarization one of the component beams pass the boundary surface unhindered and the other of the component beams are reflected on the boundary surface so that the two component beams are combined in the area of the boundary surface and leave the beam splitter and beam combination unit essentially at the same location in the same direction, wherein the beam shaping unit comprises a polarization rotation element which can rotate the linear polarization of one of the two component beams, wherein the polarization rotation element is made as a prism which is arranged such that the cross section of the corresponding component beam is turned during passage through the prism, in this way the corresponding rotation of the linear polarization of this component beam taking place.