Abstract: A high-resolution radiation detector is formed by viewing a scintillation crystal with an electronic camera through an optical lens assembly. The material of the scintillation crystal is selected to have a high density, contain a high atomic number element, and have a high index of refraction, such as Bismuth Germinate Oxide, Cadmium Tungstate, or Gadolinium Silicate. A light absorbing coating is applied to the radiation entry surface of the scintillation crystal to further increase the spatial resolution of the detector. In some embodiments of the invention, the optical lens assembly has a large f-number, providing further improvements in spatial resolution.