LENS COUPLED SCINTILLATING SCREEN CCD X-RAY AREA DETECTOR WITH A HIGH DETECTIVE QUANTUM EFFICIENCY

An X-ray area detector consisting essentially of a scintillating screen, a fast objective and a cooled 1242 x 1152 slow can CCD camera is described. A detective quantum efficiency (DQE) of > 0.3 for a planar field of view of empty set 110 mm and photon energies between 10 and 20 keV is obtainable at integrated intensity levels above 10(8) eV/mm2/readout without any image intensification. At lower intensities the readout noise of the CCD camera (8 e-/pixel) deteriortates the DQE. The spatial resoslution of the detector is 100 mum (FWHM) and the dynamic range 10(4). The design easily allows the exchange of screens in order to optimize the detector at other photon energies. The performance of the detector will be discussed in terms of DQE, dynamic range, spatial resolution, spatial distortion and uniformity of response. The detector will be initially used for small angle scattering and diffraction experiments as part of the Microfocus Beamline at the European Synchrotron Radiation Facility (ESRF).