X-rays and radiography

Abstract

X-rays were discovered in 1895 by the German physicist Wilhelm Conrad Roentgen. During the course of experiments on electrical discharge tubes he noticed that a screen coated with barium platinocyanide glowed when placed near the tube. After further investigation he concluded that the fluorescence was being caused by invisible rays which were capable of penetrating not only glass but also optically opaque materials. He also found that he could photograph the interior of objects. For example the bone structure of the hand could be photographed because the bone attenuates X-rays to a greater extent than the soft flesh. Photographs obtained by passing X-rays through objects (or people) in this way are known as radiographs.