Deterministic processes for manufacturing conformal (freeform) optical surfaces

This paper describes the computer-controlled machines and deterministic processes developed by the Center for Optics Manufacturing (COM) at the University of Rochester to produce conformal windows and domes that have non-traditional optical surface geometry and unusual shapes. COM's DMG (deterministic microgrinding) technology produces aspheric and conformal (freeform) surfaces in minutes, versus the weeks that are required to produce the surfaces conventionally. The demonstrated techniques and equipment provide a predictable and repeatable optical production process for just about any IR, visible, or UV material. The DMG process, in concert with newly developed CNC machining equipment, typically yields 1.0 wave peak-to-valley form accuracy, 150 Angstroms rms surface finish, and subsurface damage levels low enough that some of the infrared materials do not require additional polishing.