Active Alignment Technique for Measuring Tilt Errors in Aspheric Surfaces During Optical Assembly Using Lens Alignment Station (LAS)

摘要

An optical alignment system and corresponding method measures tilt errors of one or more optical surfaces, including aspheric surfaces, using interference patterns created by an illumination of the edges of an optical surface. An exemplary optical alignment system comprises a test mount centered on (and configured to rotate about) an axis, a laser, a detector and a processing circuit. The laser directs laser light along the axis to illuminate a test surface of an optical assembly disposed in the test mount. The detector detects a tilt orbit of an interference pattern produced in a first image plane perpendicular to the axis when the test mount rotates about the axis. The first image plane is spaced from a second image plane (e.g., paraxial ray focus plane) by a difference Δh. The processing circuit determines a tilt error θ of the test surface from the detected tilt orbit and the difference Δh.