This article describes the revision of a lecture in optical engineering based on an evaluation of university teaching by students. Although this evaluation method is widely accepted and investigated, only few practically oriented reports on the deduction of teaching improvements from the evaluation's results on lectures are available. Our approach is the analysis of evaluation results by applying the principles of the explorative factor analysis (EFA). The changes that were derived from this analysis were mainly focused on a revision of the course structure and its presentation style.Finally, the impact of the modifications was measured by the evaluation of the lecture after the completed revision. The later evaluation showed improvements in all intended areas of interests illustrating the benefit of thorough revisions for the quality of teaching.