Cooled CCD camera with tapered fibre optics for electron microscopy

A CCD camera for use in electron microscopy, with 1286 x 1152, 37 mu m pixels and an input aperture of 60 mm diameter, is described in this paper. An attempt is made to optimise the phosphor resolution for 120 keV electrons using Monte-Carlo simulation methods. Incident electrons are converted to visible light in a polycrystalline phosphor (P43) deposited on tapered fibre optics and imaged on to a cooled slow-scan CCD which is controlled from a Sun spare-station, running under a Unix platform, through a VME-based drive and read-out electronics system. The camera is attached to a Philips CM12 microscope and is used mainly for recording electron-diffraction patterns from two-dimensionally ordered protein arrays. Data can be displayed rapidly on the Sun monitor and can also be transferred for further analysis to a Dec Alpha computer via Ethernet for application of various image-processing programs.