Sub-aperture stitching for data measured on spherical and aspherical lenses using interferometry

Abstract

In order to measure an optical lens surface shape using optical interference with sufficient accuracy, it is usually necessary divide area into sub-apertures and then captures each sector separately. When the data are acquired, it is necessary to merge elements together for further analysis. This paper is primary about stitching sub-apertures on spherical and aspherical optical lens. The main content of this paper is mostly the description of a stitching procedure and troubleshooting during process. The paper for example contains a description how sub-apertures tilt was compensated and how sub-apertures rotation was solved. Another topic in this paper is dealing with final adjustment during stitching. The paper contains description for used algorithms. For example an algorithm for finding a sub-aperture centre and algorithm for overlap deviation evaluation are included in this paper. Very useful part in this paper is the description of used computational complexity optimisation methods. And finally real measured and processed data are presented.