Working flat out

The X-ray tube has been the workhorse of medical imaging systems for nearly 100 years. In such a tube, a high-voltage potential is applied across a cathode and an anode, accelerating electrons towards the anode or metal target.

When the electrons collide with the target, they lose their energy and X-rays are emitted. Although effective, X-ray tubes have some limitations.

They are expensive to manufacture and replace, they are fragile and they burn out frequently. In addition, vacuum tubes require high-voltage electronic support systems to create and accelerate the electron beam, as well as associated shielding, which increases their capital cost and weight.

Vacuum-tube-based solutions are also heavy; even existing ’portable’ solutions can weigh 100kg or more. As a result, taking radiological equipment based on them to a patient can be impractical. As even portable systems emit a conical beam of X-rays, it is vital to keep a specificdistance from a patient to obtain an image and to avoid radiation over-exposure to the skin.