Advanced optical imaging techniques and bio/medical applications

Optical microscopes have revolutionized biology and medicine by visualizing small worlds beyond human vision, but still need improved performance or new imaging capabilities. In this regard, we are developing novel optical microscopy methods, considering both hardware (based on physical, chemical and engineering principles) and software (based on machine learning, denoising, deconvolution and others in the name of computational imaging). We are also interested in independent or collaborative bio-application research made possible by our novel tools.

(1) Super-resolution microscopy

Single-molecule localization microscopy (SMLM, aka STORM) is a cellular fluorescence imaging technique with revolutionary imaging resolution down to 20 nm (awarded the Nobel Prize in Chemistry 2014). For its broader applicability toward tissues and small animals, Dr. Kim has developed a new STORM platform (obSTORM in Nature Methods 2019) based on oblique light-sheet imaging. Here at SNU, we are innovating imaging resolution and speed in cell- and tissue-level STORM and discovering new nano-scale biological structure that has never been explored.

(2) High-speed volumetric imaging

While many biological phenomena in living samples occur in three dimensions in real time, it is difficult to visualize them at good spatio-temporal resolution. Based on light-sheet microscopy and computational imaging approaches, we are developing rapid volumetric imaging tools, targeted for cellular and developmental biology, which enable time-lapse 3D observation of rapidly changing biological events.

(3) Advanced Optical Imaging Theory and Computational Imaging

It may seem simple to focus light or image an object through a “lens”, but its accurate theoretical prediction can be very complicated (or even impossible) for a large numerical aperture lens used in microscopy and lithography. We are interested in utilizing our lab’s theoretical expertise in rigorous image formation (such as partially coherent imaging and vector diffraction theory) to develop a variety of important applications: point spread function (PSF) engineering, super-resolution imaging, quantitative phase imaging, adaptive optics, etc. It is also of our interest to apply computational approaches like deep learning to these applications. (* J. Kim et al., JOSAA 35, 526-535, 2018)

Optical manipulation technology

Optical tweezers, a fascinating scientific concept to grab and manipulate microscopic objects like nano particles or cells (awarded the Nobel Prize in Physics 2018), have opened a new door to biophysics research. We are interested in advancing this manipulation technique in a new fashion, combined together with our rapid 3D imaging tool, to enable real-time 3D monitoring/control for broader applications including but not limited to cell mechanics, cell sorting, and optogenetics.

Biophotonic devices and systems

Based on the previous research in lasers, plasmonics and metamaterials (see below), we are interested in devising new photonic devices/systems for biological, healthcare and industrial applications, with an emphasis on new cellular research, medical diagnostics and therapeutics and bio/chemical sensing.

References: Wong et al., Nature Photonics 10, 796-801 (2016); Xia et al., Nano Letters 19, 7100-7105 (2019); Shitrit et al., Physical Review Letters 121, 046101 (2018)