High-resolution wide-field microscopy with adaptive optics for spherical aberration correction and motionless focusing.

Live imaging in cell biology requires three-dimensional data acquisition with the best resolution and signal-to-noise ratio possible. Depth aberrations are a major source of image degradation in three-dimensional microscopy, causing a significant loss of resolution and intensity deep into the sample. These aberrations occur because of the mismatch between the sample refractive index and the immersion medium index. We have built a wide-field fluorescence microscope that incorporates a large-throw deformable mirror to simultaneously focus and correct for depth aberration in three-dimensional imaging. Imaging fluorescent beads in water and glycerol with an oil immersion lens we demonstrate a corrected point spread function and a 2-fold improvement in signal intensity. We apply this new microscope to imaging biological samples, and show sharper images and improved deconvolution.