The first cathode ray tube scanning device was invented by the German scientist Karl Ferdinand Braun in 1897. Braun introduced a cathode-ray tube with a fluorescent screen, known as the cathode-ray oscilloscope.

Braun, a German physicist shared the Nobel Prize for Physics in 1909 with Guglielmo Marconi for the development of wireless telegraphy. He demonstrated the first oscilloscope (Braun tube) in 1897, after work on high frequency alternating currents.

Cathode-ray Oscilloscope
The cathode-ray oscilloscope is an electronic display device containing a cathode-ray tube (CRT), used to produce visible patterns that are the graphical representations of electrical signals.

Karl Ferdinand Braun
Though Karl Ferdinand Braun shared, with Guglielmo Marconi, the 1909 Nobel Prize in Physics for achievements in wireless telegraphy, he is rarely remembered for that honor. He is better known for building the first cathode ray tube (CRT), or "Braun tube" as it is still known in Germany, in 1897.

Ferdinand Braun - Cathode Ray Tube
Ferdinand Braun shared the 1909 Nobel prize with Marconi "in recognition of their contributions to the development of wireless telegraphy". View an actual 1897 Braun Tube (Braunsche Röhre).

Karl Ferdinand Braun, Dr : 1850 - 1918
Braun, who spent his career as a professor of physics at German universities, increased the range of Marconi's transmitter, invented the crystal rectifier (a device that allows current to flow in only one direction, and improves radio transmission), and later invented the oscilloscope, a cathode-ray-tube laboratory device that was the forerunner of today's television and radar tubes.

Ferdinand Braun
In 1874, Karl Ferdinand Braun (1850-1918) discovered one way conduction in metal sulfide crystals. Radio receivers required a device called a rectifier to detect signals. He used the rectifying properties of the galena crystal, a semiconductor material composed of lead sulfide, to create the cat's whisker diode for this purpose. Thus was born the first semiconductor device.

Related Innovations
History of the Cathode Ray Tube
Telegraphy
The History of Television

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