Metrology System Enhancement for Advanced Optical Systems

Modern optical designs can deviate from traditional spherical and aspherical shapes in order to maximize overall system performance. For the case of missile domes, the overall system performance can include other factors aside from optical performance such aerodynamic drag, time to target, and damage sustained from environmental conditions. To account for these factors, the traditional spherically shaped dome is replaced by a bullet like ogive shape.  While these aerodynamically optimized shapes provide superior performance, they present challenges to both the manufacturing process and the ability to measure them to precision optical tolerances. OptiPro already has the technology to measure complex optical components using its UltraSurf non-contact metrology system. Therefore, effort will be focused on improving performance and precision of the current commercial version of the UltraSurf system, but the system is unable to achieve current advanced optical system tolerances. The main objective is to determine the feasibility of adding a reference frame to the UltraSurf in-order to improve the overall stability and accuracy of the machine. A reference frame is thermally stable and mechanically stiff structure that can be coupled with high-resolution optical feedback. The result is a machine that can position accurately on the nanometer scale. With this Phase I effort, OptiPro plans to demonstrate the ability to accurately measure the surface irregularity to higher precision than previously achieved. Once the feasibility is proven a full system will be proposed that takes advantage of the reference frame technique for measuring the advanced optical systems within the Air Force Research labs and DoD prime contractors.