An X-ray television system for rapid recording and processing of diffraction patterns

An X-ray television camera using a phosphor screen coupled to an image orthicon tube was prepared to detect and record diffraction patterns rapidly. It is about 750 times more sensitive than photographic film, producing a video signal of S/N = 10 for incident 4 × 10⁴ Cu Kα quanta sec⁻¹ mm⁻², and has a dynamic range of 1:30 and a spatial resolution of 6.4 Lp mm⁻¹. The detector system was tested by recording rotation patterns from a single-crystal of diformylhydrazine, where it was demonstrated that one can measure reflection intensities with an accuracy better than 10%. To process the TV picture by computer, an image readout device using a storage tube was built. The high sensitivity and the large detection window (42 mm in diameter) of the camera and the fast speed (40 μs for each 80 × 80 μm resolution element) of the readout device make the incorporated system most appropriate for rapid measurement of simultaneous reflexions from macromolecular crystals. The camera can also record small-angle diffraction patterns from muscle in an exposure time of a few seconds.