Information on the structure and function of proteins is important for unveiling biological processes taking place on a molecular level. X-ray crystallography has been successful in determining protein structure, however, it is not well suited for analyzing hydrogen atoms and water molecules. It has been shown that the thermal neutrons are a far better tool for probing interactions between proteins and water, because they interact directly with light nuclei, not their electron clouds as in case of x-ray diffraction. However, the use of thermal neutrons has been underutilized, partially due to the lack of adequate detectors. Current two-dimensional detectors for neutrons do not provide adequate area coverage, spatial resolution, sensitivity, and geometry best suited for the given application. To address these issues, we propose to develop a large area digital imaging detector for thermal neutrons, which offers a better combination of surface coverage, spatial resolution, detection efficiency and dynamic range than is currently possible. The detector is based on a novel, large-area scintillator, tailored for imaging thermal neutrons, coupled to a digital readout. This thermal neutron imaging system will advance the state-of-the-art of detectors used in macromolecular crystallography and neutron radiography. High resolution neutron imaging will provide better insights into biological systems, and polymers and other ordered structures. For example, it will provide better understanding of disease progression, improved insights into viral structures through neutron diffraction studies. The proposed detector could be employed at any neutron source facility and would help to advance basic research in protein mechanisms as well as drug design. Non-biomedical applications could be found in non-destructive testing and secuity scanning at entry ports and strategic facilities. [unreadable] The goal of this Phase II project is to develop at high spatial resolution scintillator for neutron macromolecular crystallography, which compliments x-ray crystallography in its ability to precisely locate hydrogen atoms in protein molecules. The information on hydrogen location is important for monitoring protein dynamics and helps to understand nature of disease. The proposed detector could be employed at any neutron source facility and would help to advance research of protein mechanisms as well as drug design. [unreadable] [unreadable] [unreadable]