Methods and apparatus of aligning surfaces

Abstract

Ultra-precision freeform surfaces are important to the development of complex and micro-optical-electro-mechanical devices used in many photonics and telecommunication products such as F-theta lenses for laser printers. These surfaces are complex and large scale surface topologies with shapes that generally possesses no rotational symmetry. Due to the geometrical complexities of these ultra-precision freeform surfaces, it is difficult to characterize the form accuracy and surface quality of freeform optical surfaces. The method of this invention is based on feature-point pre-fixture, and iterative precision alignment algorithm, which can provide sufficient capability of form characterization for ultra-precision freeform surfaces with form accuracy down to below sub-micrometer range.