Microfocus X-ray tubes for very large geometric magnifications
Open microfocus X-ray tubes have an umlimited lifespan and make very strong magnification possible.
X-ray radiation is caused by fast-moving electrons that collide with a solid body. The electrons are generated in a vacuum by a glowing filament (cathode). In the case of open microfocus tubes, this filament can be replaced. As a result, the lifespan for this type of tube is unlimited. The freely moving electrons are accelerated within the vacuum by an electrical field. This field lies between the filament and the centering coils (alignment unit).
The special features of microfocus X-ray tubes in comparison to conventional X-ray tubes are the centering coils and the focusing coils (objective lens). The centering coils center the beam of electrons so that it hits the target in the center. The focusing coils focus the electrons on the target. As a result, the beam source measures only a few micrometers. The fact that this beam source is so extremely small means that a several thousandfold geometric magnification can be achieved.
This technology is used in the YXLON X-ray systems Y.Cheetah and Y.Cougar.