Distortion mapping correction in aspheric null testing

摘要

We describe methods to correct both symmetric and asymmetric distortion mapping errors induced by nulltesting elements such as holograms or null lenses. We show experimental results for direct measurementand correction of symmetric mapping distortion, as well as an example result for analytical mappingperformed using an orthogonal set of vector polynomials for asymmetric correction. The empiricaldetermination of symmetric distortion is made via calculation from predicted and measured changes toaberrations induced via known changes to the testing point.