Sherry has been tackling a challenging optical modeling problem that is critical to the next generation of single-molecule microscopy methods. Single-molecule microscopy has, over the past ten years, evolved from a method of identifying and locating single molecules to using polarization to identify molecular orientation, an approach that is seen as critical to unraveling the mysteries of protein folding and similar challenges in multidimensional microscopy. Sherry is tackling the problem of calibration both theoretically and experimentally. She is building a microscope system to simulate a linear dipole emitter in three dimensions in a high-NA optical microscope in a way that will allow us to calibrate polarization dependent point spread functions. She is also working on a new software tool to simulate single-molecular emitters as well as nanoparticle phantoms. Of special interest is her work, done as part of Professor Julie Bentley’s lens design class, on the design and analysis of a high-NA objective for single molecule microscopy.  In this effort, Sherry went beyond simply the objective design to include optimization of the relay system and analysis/correction of the fluorescence spectral width over which the single-molecule microscope would be well corrected.

Sherry is also participating in a project on the design, implementation, calibration, and testing of a new super-resolution fluorescence polarization microscopy technique that provides information about the 3D position, 3D orientation, and wobbling of collections of molecules. Her research work has so far led to one article about the use of fluorescent beads and polarizing optical elements for the calibration of novel fluorescent polarization microscopy techniques. While the focus is on the new technique she is developing, the analysis applies to any fluorescent microscopy technique. A second manuscript on this topic is currently nearing completion.

Sherry is also writing Python code to model this type of microscope, which will help with the design of the birefringent masks she uses. She is also starting work on a new experimental technique to calibrate this type of microscopy system using a metallic nanotip that generates a dipolar field with controllable orientation.