title: Interferometric testing of high-numerical-aperture convex surfaces.
abstract: Interferometric tests of convex surfaces for large-N.A. lens systems often present problems. We show how such surfaces can be tested with a reference surface having a much smaller N.A. by making use of the aplanatic imaging properties of a spherical surface.
authors.forename: K
authors.initials: K
authors.lastname: Creath
authors.forename: Y A
authors.initials: YA
authors.lastname: Gilliand
authors.forename: P
authors.initials: P
authors.lastname: Hariharan