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Dr. Tsubokura's Radiation Lecture Vol.91

Author: Masaharu Tsubokura

Editors: Akihiko Ozaki M.D., Yuki Senoo

181. Rontgen, the father of diagnostic radiology/X-rays

There are many technical terms related to the field of radiation, such as Becquerel, Sievert, and X-ray (In Japanese, X-rays are called Roentgens). Many of these words are derived from the names of scientists who made significant contributions to radiation-related research.

For example, in 1895, Wilhelm Rontgen, a German physicist, conducted an experiment to evaluate a quality of an electric current passing inside an evacuated glass tube. This experimental device became a prototype for a cathode-ray tube built in an old TV.

During this experiment, Rontgen noticed that a fluorescent plate placed near the glass tube was glowing, even though the glass tube was tightly covered with black paper. In observing this phenomenon, he hypothesized that "something invisible" was coming out of the glass tube and causing the fluorescent screen to glow. He named that "something invisible" an "X-ray," as the letter "X" is often used in mathematics to mean an unknown value.