@incollection{MIP-0710,
author="T. Hanning, O. Smirnow",
title="On the point spread function introduced by first order optics",
institution="Fakult{\"a}t f{\"u}r Informatik und Mathematik, Universit{\"a}t Passau,
year=2007,
number={MIP-0710}
}
In computer vision the blurring of observed objects in an image is modeled by a convolution with a point spread function (PSF). The extraction of basic image feature like points, lines, circles or ellipses is done generally without knowing the PSF exactly. Therefore, the point extraction must result in an erroneous position. In this article we show that even for first order optics the point spread function is not symmetrical. Furthermore, we show that it depends on the position of the observed point. Therefore, for optical measurement systems any feature point extraction should be corrected with respect to this position.
