Dual Mode T-DHM/IR Spectral Sensor for Time-resolved Pathogen Imaging

Physical Sciences Inc. (PSI) proposes to develop a dual-mode, nanometer-scale, 3D optical imaging system that combines tomographic digitalholographic microscopy (T-DHM) with infrared (IR) absorption spectroscopy. The proposed sensor will be capable of generating high data rate,sub-wavelength axial/lateral resolution, 3D structural images with simultaneous and complementary functional information of micron-scalepathogen organisms including biological warfare agents. This capability will enable real-time observation of the organisms for structural(conformational) and functional (chemical) changes in response to external stimuli such as therapeutics or antibiotics. In the Phase I program,PSI will develop a system model projecting the overall performance of the T-DHM/IR sensor. The model will be validated through the buildand characterization of a breadboard sensor coupled with standard holographic and filtered backpropagation tomographic reconstructionalgorithms. The breadboard will be used to demonstrate 3D functional measurement of polystyrene spheres and non-infectious E coli. Finally,a conceptual design will be generated for a prototype T-DHM/IR sensor to be developed and validated in full in a Phase II program.