This Small Business Innovation Research Program Phase I project will demonstrate innovative new technology for high precision, non-contact 3D imaging and metrology with order of magnitude improvement in lateral resolution, depth of field, and measurement speed over existing commercial optical profiling methods. This technology, called Multistatic Spectral Interferometry (MSI), combines diverse cutting edge technological developments in swept-wavelength interferometry (SWI) and multistatic radar processing. Unlike conventional optical metrology approaches, MSI does not rely on lens based imaging, pixelated image sensors, or mechanical scanning. As a result, MSI can perform 3D surface profile measurements with nanometer level precision in all three dimensions throughout an extended measurement volume, all acquired with a single wavelength sweep of a tunable laser. This approach will enable new solutions to unmet market needs for metrology of high-slope, high-aspect ratio components such as molded aspheric optics. This program will demonstrate the feasibility of MSI though detailed numerical simulation of the system together with experimental verification. The anticipated results will demonstrate the capability of MSI to meet critical market needs and provide a computational framework for design and modeling of MSI systems.
The broader impact/commercial potential of this project includes addressing a critical commercial need within the multibillion dollar CMOS camera market and strengthening research collaborations and technology transfer between industry and academia. Ever increasing image quality requirements for cell phone cameras and other miniature imaging systems have driven the need for new metrology capabilities for rapidly testing diamond turned molds and molded aspheric optics. These components require nanometer level shape tolerances in three dimensions, while their high slopes and high aspect ratios render existing surface profilometry solutions unsuitable. This program will demonstrate the ability of MSI to meet critical market requirements, leading to commercialization of MSI technology, associated job growth, and availability of new measurement capabilities. Through collaboration between industry and academia, this program will promote meaningful educational, research, and mentorship opportunities for engineering students. Additionally, this program will leverage and expand academic research infrastructure, improving available research tools. Development of MSI technology and successful commercialization will provide greatly increased metrological capabilities over current state of the art instrumentation. Improved measurement technology drives improved fabrication and manufacturing technologies, enabling further technological advancement across a wide range of industries and providing new tools for advancing discovery and understanding.
This Small Business Innovation Research Phase I project demonstrated the technical feasibility of an innovative new technology for high-precision, non-contact 3D surface profiling called Multistatic Spectral Interferometry (MSI). This novel measurement technique combines optical methods previously applied to biomedical imaging and fiber optic component testing with data processing algorithms originally designed for radar and radio astronomy to achieve extremely precise measurements of 3D surface profiles. Unlike most conventional optical profiling methods, MSI does not rely on lens-based imaging, pixelated image sensors, or mechanical scanning. As a result, MSI can perform surface profile measurements with nanometer accuracy even for objects with steep angles, high aspect ratios, or substantially deviate from spherical or planar geometries, which are difficult or impossible to measure to the required accuracies using conventional means. This capability can meet a critical need for precision metrology of aspheric optics in the CMOS camera market, where increasing image quality requirements for cell phone cameras and other applications have driven the need for new and improved measurement capabilities. This Phase I research program demonstrated the feasibility of MSI through a combination of numerical system modeling and proof-of-principle experiments, setting the stage for the development of a complete MSI system prototype in Phase II. In addition to the development of a promising new technology that advances the state of the art in precision metrology, this Phase I program has had broader impacts by promoting teaching, training, and learning, as well as by enhancing infrastructure for research and education. A key component of this Phase I program was a research partnership between Chiaro Technologies and the University of Colorado at Boulder that is expected to continue in Phase II. This partnership provided funding for a postdoctoral researcher, and provided a forum for meaningful collaboration between industry and academia.
