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While polarization sensing is vital in many areas of research, with applications spanning from microscopy to aerospace, traditional approaches are limited by method-related error amplification, accumulation, and pre-processing steps, constraining the performance of single-shot polarimetry. Here, we propose a measurement paradigm that circumvents these limitations, based on the use of a universal full Poincaré generator to map all polarization analyzer states into a single vectorially structured light field. All vector components are analyzed in a single shot, extracting the vectorial state through inference from a physical model of the resulting image, providing a single-step sensing procedure. To demonstrate the feasibility of our approach, we use a common graded index (GRIN) optic as our mapping device and show mean errors of < 1 % for each vector component. Our work paves the way for next-generation polarimetry, impacting a wide variety of applications that rely on vector measurement.

We present two FLIM endoscopes for clinical imaging and in vivo cell biology. For subcellular confocal imaging we demonstrated the first confocal FLIM endomicroscope, implementing TCSPC with a Cellvizio®GI, which we have now developed as a self-contained wheeled instrument (1.0 × 0.7 m) incorporating a tunable excitation laser and acquiring images in < 10 s. This has been applied to image FRET in live cells and to image tissue autofluorescence, for which we are implementing "FIFO" for image montaging. For diagnostic screening/guided biopsy, we have developed a complementary wide-field FLIM endoscope employing time-gated detection with violet and UV excitation for imaging over mm-cm fields of view.

We demonstrate that spectral selection from a supercontinuum generated in a microstructured fibre can provide a continuously electronically tunable ultrafast spatially coherent source for confocal microscopy and both scanning and wide field fluorescence lifetime imaging. © 2005 Optical Society of America.