Optical tests of large hyperbolic secondary mirrors has been always challenging. Many methods have been proposed and used in the past, including different combinations of auxiliary optics and configurations. Starting from a review of known methods, a new approach has been identified that offers a wide range of applicability, being modular and reusable for other applications. Two classes, one based on traditional null lens optics and a new one that relies on computer-generated holograms, are described.
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