Single crystal and powder neutron diffraction can be enhanced through the use of polycapillary focusing optics for convergent beam neutron crystallography. Using polycapillary optics, neutrons can be focused into a small spot resulting in an increased neutron current density on the sample. Polycapillary optics can also provide large gains over conventional unfocused neutron beams. Convergent beam neutron crystallography using capillary optics can be effectively used in crystal structure or phase distribution studies for small samples of small-to-medium-size molecules. This is particularly important for ultra high pressure or low temperature measurements. Enhanced thin film analysis Powder diffraction using neutron focusing optics enables the analysis of small samples or weakly diffracting polycrystalline materials such as polymers. High spatial resolution studies of strain, phase, and texture distributions in extended samples may also be possible.