Capturing the unique coherence properties of lasers and making use of the new advances in data acquisition and processing, we develop new technologies for high speed 3D imaging of biological materials at the micron scale. As an example, we use Optical coherence tomography (OCT) to visualize tissue morphology, as well as its function by monitoring its blood perfusion or birefringence changes. We also combine OCT with other imaging or spectroscopic techniques, such as confocal microscopy, fluorescence imaging, Raman spectroscopy, etc. to provide a more complete image of the tissue morphology and function. Applications include investigations of the morphological and functional changes of the epithelial and intersitial tissue, as well as retinal imaging, with the goal of diagnosing various diseases, guiding therapies, or monitoring therapy response.