In an X-ray generator device a target member emitting X-rays by electron bombardment is arranged in a rod-shaped tubular probe and is provided with a conically tapering front part facing a comparatively narrow aperture in a controlling electron beam diaphragm for the purpose of forming a substantially...http://www.google.es/patents/US4563769?utm_source=gb-gplus-sharePatente US4563769 - X-Ray generator device
