Structure of the modern schiefspiegler I Pseudo axis, magnification, and distortion

Abstract

The modern schiefspiegler is an optical system consisting of two prolate spheroid mirrors coupled by conjoining the distal focus of the first spheroid with the proximal focus of the second. A ray through the proximal focus of the first spheroid must, after reflection, pass through the common focus and then, after a second reflection, through the distal focus of the second spheroid. The pseudo axis is such a ray with the property that all other meridional rays are symmetric about it. The entrance and the exit pupils are perpendicular to the pseudo axis and are located, respectively, at the first proximal focus and the second distal focus. Therefore rays through the foci are chief rays. It is shown that all chief rays are symmetric with respect to the pseudo axis and that, therefore, magnification is uniform for all object points. An expression for magnification is obtained that leads to a distortion function that depends only on magnification.