Asphere Metrology

Options for measuring aspheric lenses

This paper will outline the numerous metrology options for aspheres at Optimax, including how they work, any requirements, and what is specified with each method in an effort to help reasonably tolerance aspheres. Effects on the fabrication and cost of the lens will also be discussed. Metrology of aspheres fits into three basic categories: physically measuring the form of the optical surface, reflected wavefront testing, and transmitted wavefront testing. Each category has different methods of testing with varying degrees of accuracy.