X-ray are electromagnetic radiations. These radiations have extremely short wavelengths
ranging from 0.1 to 10 nanometers. They are emitted by atoms when electrons fall from a higher energy shell to a lower energy shell. X-ry have high energy.
Nikola Tesla investigated X-ry in 1887 by using high voltages and vacuum tubes. He
invented a single-electrode X-ray tube different from other tubes, which had no target electrode. His X-ry tube was based on a principle known as the Bremsstrahlung process. According to this process, when charged particles such as electrons pass through matter, high-energy secondary X-ry emission is produced. IHe performed many experiments. However, he could not categorise the X-ry.
X-ry were first generated and detected by Femando Sanford in 1891, when he was studying about cathode rays. Cathode rays are streams of electrons observed in vacuum tubes.When voltage is applied across separate electrodes, cathode rays are produced in vacuum tubes.
Heinrich Hertz started his experiments in 1892 He demonstrated that cathode rays can penetrate very thin metal foil. His student, Philipp Lenard, researched and developed a version of the cathode tube He studied how X rays penetrated various materials. He produced X-ry without realizing it. Hermann von Helmholtz devised the mathematical equation for X-ry. He proposed his dispersion theory based on the electromagnetic theory of light but it did not work with X-ry.
Wilhelm Conrad Roentgen was a German physics professor. He began his observations of X-rays while doing experiments with vacuum tubes in 1895. He categorised the X-rys
and referred to it as X stating it as an unknown type of radiation. Roentgen received the first Nobel Prize in Physics for his discovery. X-rays are also called Roentgen rays
Roentgen noticed a faded green light against the wall while working on an old cathode ray
generator, projected through a glass vacuum tube. The light travelled through various
materials such as paper, wood, and books. He also noticed the outline of the bones of his hand displayed on the wall. Roentgen discovered the medical use of X-rys when he saw his wife’s hand on the photographic plate that was formed due to x rys.
Some more developments in the history of X-rays
Charles Barkla discovered in 1906 that X-rays could be scattered by gases.Max von Laue, Paul Knipping, and Walter Friedrich observed the diffraction of X-ray by crystals in 1912.
Karl Manne Georg Siegbahn discovered the M series of X-ray with newer wavelengths in 1913 He also proved that X rys are refracted like light rays when they pass through prisms X-ry tube.William David Coolidge invented the X-ray tube that contained a tungsten filament. This tube was known as Coolidge tube. It was the first stable
X-ry generator used in radiology. The X ry machines using Coolidge tube could easily detect deep-rooted tumours.
The X ry microscope is an instrument that produces images of very small objects using
X ry. It was first developed by Kirkpatrick and Baez in 1948. It produces images of very small objects by using electromagnetic radiation in the soft X ry band. The X rays do not reflect or refract casily and are invisible to the human eye. Early microscopes used grazing-incidence reflective optics to focus the X ray while the modern microscopes use a charge coupled device to detect X ry.