Collaborative Research: Manufacturing of Complex Optical Elements for Advanced Imaging Systems

University Of North Carolina At Charlotte, Charlotte NC

Investigators

Abstract

This grant supports research that contributes new knowledge related to an advanced manufacturing process that is required for creating complex optical components. It will promote the advancement of science and strengthen our national capabilities for manufacturing of advanced optical systems. Ultra-precision machines utilize single crystal diamond tools to manufacture optics with dimensional accuracies that are on the order of a small fraction of the diameter of a human hair, approximately one ten-millionth of one meter. New ultra-precision machine technology enables the manufacture of optics of nearly arbitrary shape, known as freeform optics. This freedom allows optics designers to think in entirely new ways. As one of the enabling technologies for freeform optics, ultra-precision machining is poised to play a major role in an optical revolution. A prime application area of this technology is the manufacture of optics for thermal imaging and night vision systems. This award supports fundamental research needed for the cost-effective manufacture of freeform optics. While the immediate impact area is thermal imaging, the research has broader application to many industry sectors critical to the U.S. economic sectors including solar energy, healthcare, biomedical, aerospace, defense and automotive. This research crosses the disciplines of manufacturing, mechanical engineering, materials science and optical science and the multi-disciplinary approach is used to broaden participation of underrepresented groups in research and positively impact engineering education. The research objective of this researched study is to test the hypothesis that there is a shift in material removal mechanism at increased cutting velocities when single point diamond machining brittle single crystal materials such as germanium or silicon. Ultra-precision diamond machining experiments will be performed at the University of North Carolina at Charlotte that are designed to explore the effect of increased cutting velocities on the governing cutting mechanics. The study will focus on 1) high speed diamond flycutting, 2) high speed orthogonal cutting using a fast tool servo to allow rapid tool withdrawal from the cut, and 3) ohmic contact cutting to explore the possibility of a material phase change. High bandwidth dynamic forces, chip morphology and changes in material phase, if any, will be quantified. The surface and subsurface of the machined specimens will be characterized by atomic force microscopy, channeling Rutherford backscattering spectrometry, Raman spectroscopy and cross-sectional transmission electron microscopy to be performed at Oklahoma State University and Los Alamos National Laboratory. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.