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Caltech Brain Imaging Center Seminar

Friday, June 21, 2024
10:30am to 11:30am
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Online Event
Photoacoustic, Light-Speed, and Quantum Imaging
Lihong Wang, Bren Professor of Medical Engineering and Electrical Engineering; Andrew and Peggy Cherng Medical Engineering Leadership Chair; Executive Officer for Medical Engineering, Caltech,

Abstract: We developed photoacoustic tomography (PAT) to peer deep into biological tissue. PAT provides in vivo functional, metabolic, molecular, and histologic imaging across the scales of organelles through organisms. We also developed light-speed compressed ultrafast photography (CUP) to record 219 trillion frames per second, orders of magnitude faster than commercially available camera technologies. CUP can record in real time the fastest phenomenon in nature, namely, light propagation for the first time and can be slowed down for slower phenomena such as neural conduction. We are exploring quantum entanglement for imaging.

PAT physically combines optical and ultrasonic waves. Conventional high-resolution optical imaging of scattering tissue is restricted to depths within the optical diffusion limit (~1 mm). PAT beats this limit and provides centimeter-scale deep penetration at high ultrasonic resolution and high optical contrast by sensing molecules. Broad applications include early-cancer detection and brain imaging. The annual conference on PAT has become the largest in SPIE's 20,000-attendee Photonics West since 2010.

CUP with a single exposure can image transient events occurring on a time scale down to 10s of femtoseconds. Akin to traditional photography, CUP is receive-only—avoiding specialized active illumination required by other single-shot ultrafast imagers. CUP can be coupled with front optics ranging from microscopes to telescopes for widespread applications in both fundamental and applied sciences, ranging from biology to cosmophysics.

Quantum imaging at the Heisenberg limit improves spatial resolution linearly with the number of quanta, faster than the square-root standard quantum limit.

This seminar is part of the "Future Advances in Multi-modal Neuroimaging Methods" series. Existing methods for measuring human brain function non-invasively such as fMRI, MEG and EEG have helped to considerably advance our understanding of human brain function over the past several decades. However, these methods suffer from substantial limitations in spatial and temporal resolution, thereby imposing major constraints on the kinds of neuroscience research questions that can be addressed in humans. This seminar series explores cutting-edge new technologies and methodologies for multi-modal imaging. We will ask whether such new approaches have the potential to overcome existing limitations and open up new research directions in human neuroscience over the coming decades.

For more information, please contact Mary Martin by phone at 626-395-4571 or by email at [email protected].