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The small correction volume for conventional wavefront shaping methods limits their applications in biological imaging through scattering media. We demonstrate large volume wavefront shaping through a scattering layer with a single correction by conjugate adaptive optics and remote focusing (CAORF). The remote focusing module can keep the conjugation between the AO and scattering layer during three-dimensional scanning. This new configuration provides a wider correction volume by the best utilization of the memory effect in a fast three-dimensional laser scanning microscope. Our results show that the proposed system can provide 10 times wider axial field of view compared with a conventional conjugate AO system when 16,384 segments are used on a spatial light modulator. We also demonstrated three-dimensional fluorescence imaging and multi-spot patterning through a scattering layer.

In this work, we propose a structured illumination (SI) method based on a two-photon excitation (TPE) scanning laser beam. Advantages of TPE methods include optical sectioning, low photo-toxicity, and robustness in the face of sample induced scattering. We designed a novel multi-spot point spread function (PSF) for a fast, two-photon scanning SIM microscope. Our multi-spot PSF is generated with a phase retrieval algorithm. We show how to obtain the phase distribution and then simulate the effect of this distribution on a spatial light modulator (SLM), which produces the multi-spot PSF in the object plane of the microscope. We produce simulations that show the viability of this method. The results are simulated and a multi-spot PSF scanning SIM microscope is proposed.

In traditional seeing-limited observations the spectrograph aperture scales with telescope aperture, driving sizes and costs to enormous proportions. We propose a new solution to the seeing-limited spectrograph problem. A massively fiber-sliced configuration feeds a set of small diffraction-limited spectrographs. We present a prototype, tunable, J-band, diffraction grating, designed specifically for Astronomical applications: The grating sits at the heart of a spectrograph, no bigger than a few inches on a side. Throughput requirements dictate using tens-of-thousands of spectrographs on a single 10 to 30 meter telescope. A full system would cost significantly less than typical instruments on 10m or 30m telescopes., Comment: 9 pages, 5 figures, presented at SPIE Astronomical Telescopes and Instrumentation, 23 - 28 June 2008, Marseille, France. See http://www.ucolick.org/~npk/MEMS for videos