SBIR Phase II: Closed-loop control of MEMS deformable mirror for two-photon microscopy

This Small Business Innovation Research (SBIR) Phase II project will enable video-rate three-dimensional (3D) imaging within two-photon microscopes (2PMs) by developing novel deformable membrane mirror (DMM) technology for fast, precise focus control. As a subset of laser scanning microscopes (LSMs), 2PMs achieve very high spatial resolution by using a focused, high-power laser beam to excite fluorescence via the simultaneous absorption of two low-energy infrared photons to stimulate emission in the visible spectrum. Because of the increased resolution, and increased penetration of infrared light into tissue compared with other LSM methods, 2PMs have become widely accepted for use in the life sciences, specifically for neuroscience. The DMM technology developed for this project will address the $165 million 2PM market by delivering an electrically tunable optic capable of simultaneously controlling focus and aberrations while operating an order of magnitude faster than competitive technologies. The 3D imaging capabilities enabled by this technology will propel new research in the field of neuroscience aimed at solving widespread, chronic medical problems like stroke and Alzheimer's disease. Once the 2PM entry market is addressed, this technology will be refined to address the much larger $5.8 billion 3D laser printing market. During the Phase I project, new mirror coatings were developed to handle the high-power lasers used in 2PMs. With the core DMM technology in place, this Phase II project is aimed primarily at control of mirror actuation and shape for reliable use in 2PMs. The first objective of this Phase II project will develop electronics for robust control of mirror actuation and shape. Objective two will center on refining the core DMM technology and fabrication methods to enable position sensing of the membrane and improve mirror stroke to satisfy customers in 2PM markets. The final objective will involve the creation of optical and mechanical assemblies and modules for incorporating the DMM technology into key microscopes. The result of this Phase II will be a market-ready DMM product with active focus control to address the growing 2PM market. 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.