Abstract: An optical system including a beam of radiation, an optical sensing device and boresighting apparatus. The boresighting apparatus includes apparatus for sensing the location of the beam of radiation relative to a given beam reference location and for providing an output indication thereof and including computing apparatus receiving the output indication from the optical sensing device. The boresighting apparatus further includes apparatus for defining an aiming location in the optical sensing device which aiming location is related to the output indication and including apparatus for providing an optical system reference image at a predetermined spatial separation from the beam reference location which is sensible by the optical sensing device.

Abstract: A gamma-ray camera is described including a collimator receiving and collimating the gamma rays, a converter matrix converting the gamma rays to electrons, an electron-image multiplier receiving the electrons and producing a multiplied electron output, and means for reading out the output of the electron-image multiplier.A converter matrix is described for converting gamma-rays to electrons comprising a metal plate emitting electrons upon being impinged by gamma-photons, the metal plate having a face formed with a plurality of spaced parallel surfaces which extend substantially parallel to the direction of the gamma-rays. Also described is a converter matrix of scintillation crystals, one face of each crystal including a photo-sensitive coating, the opposite face of each crystal being clear, the remaining faces of each crystal being coated with a light-reflecting coating.