SBIR Phase II: Novel Holographic 3D Optical Metrology Tool for Precision Engineering and Manufacturing

This Small Business Innovation Research Phase II project is focused on developing reliable, precise, and scalable three-dimensional sensing solutions for manufacturing and industrial processes. The three-dimensional (3D) optical metrology tool to be developed uses a high-resolution, computer-defined 3D light field to perform rapid non-contact measurements on parts during the fabrication process. Computer-defined optics enable the tool to use an adaptive process to perform 3D metrology with sub-10-micron resolution, at a fraction of the price of competing technologies. Low-volume, high-precision manufacturing plays a critical role in the global economy and is currently a limiting factor in the creation of new assembly lines, larger volume manufacturing, research timelines, and tool creation. With modern-day reliance on process automation and tighter tolerance stack-ups, scalable in-process measurements can provide critical insights into manufacturing processes. Accelerating hardware markets, such as Industry 4.0, industrial automation, automotive and aerospace manufacturing, and construction require new, advanced 3D sensors with improved reliability, precision, and ease-of-use. Surface inspection systems already account for a global $4.0 billion market, and this number will grow rapidly as new technology meets the pressing needs of these broader industrial segments. The intellectual merit of this project is founded in the underlying principles of how digital tools sense and interact with the three-dimensional world. Currently available digital tools are largely two dimensional (camera sensors and displays) or one-dimensional in nature (linear or rotary encoders). Attempts to digitally sense and interact with three-dimensional space are often based on interpolation between multiple two- or one-dimensional sensors such as stereo vision or gantry Coordinate Measuring Machines, respectively. These methods depend on several core assumptions and can result in significant errors or noise in the measurement process. By leveraging computer-generated, large field-of-view, high-precision holographic optical systems, digital measurement tools can collect precise, reliable measurements. This capability is based on the reconfigurable nature of a fundamentally three-dimensional digital technology: a computer-generated hologram. This project applies recent advances in computer-generated holograms, in conjunction with digital modeling and inverse design. The result is a novel digital measurement tool with sub-10-micron resolution over a half meter field of view. 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.