Optimal arrangement of 90 degrees off-axis parabolic mirrors in THz setups

The inherent aberrations of 90 degrees off-axis parabolic mirrors (OAPMs) are investigated. The resulting aberrations of different combinations of OAPMs for collimating and focusing the THz radiation are investigated. It is found that the arrangement with coinciding axes of the parent parabolas has a minimal geometrical optical spot of confusion. (C) 2008 Elsevier GmbH. All rights reserved.