Illumination with beams of light in unconventional polarization states departs from the usual, textbook description. Two popular examples of unconventional polarization states are radial and azimuthal polarizations (sometimes called Cylindrical Vector Beams). A wide variety of unconventional polarizations exist -- some have been well studied, while many remain unexplored. This research activity brings together three investigators that have been studying unconventional polarization states and their mathematical representation, the propagation and focusing of polarized light, and light scattering from small particles such as those found within biological cells.
This investigation makes use of a novel mathematical representation (complex-focus basis) for modeling optical focusing and scattering, the study of radial, azimuthal, and Full Poincare fields as representatives of a complex-focus basis, and the scattering of unconventional polarization states from mesoscopic particles, including cell organelles. In the process, we also address the formulation and testing of a theory of partially coherent unconventional polarization states, the coupling of unconventional polarization states to nanostructures, and develop numerically efficient theoretical models for coherent and partially coherent light propagation. We make use of the recently-introduced concept of stress- engineered optical elements to adapt an existing light scattering microscope to carry out polarization- sensitive scattering experiments. In the process, we are advancing optical physics by introducing new analytic tools for scattering analysis, a new experimental tool for rapid-acquisition pupil polarimetry, and find better ways to use polarization as a tool for improving projection imaging systems such as LCD projectors and semiconductor lithography systems.
Polarization--the vector nature of light--influences the scattering of light in profound ways, and is therefore fundamental to how we gain information about a scatterer from the scattered light. This has been used to good result in advancing cell identification for immune cell research, for example. Scattering is also important in the inspection processes that are used to guarantee high quality semiconductor circuits for computers and electronic devices. A better understanding of the physics of new polarization states will therefore have a broad impact on fields such as optical engineering and biomedical optics. The educational impact is seen annually through involvement by both undergraduates and graduate students, not merely as research assistants, but as students in training who are encouraged toward independent initiatives. Our role as educators at the Institute of Optics offers us a unique platform from which to take the results of the work, bring them into the classroom at the MS and BS levels, and to take the exciting features of polarized light with us on educational activities in area schools and science museums. Our presence at the Institute of Optics offers technology transfer to over 30 companies who are members of our Industrial Associates Program.
