Iconoscope

The Iconoscope ( from Ancient Greek εἰκών eikon " image " as well as ancient Greek σκοπεῖν skopein " look ", " look ") is a camera tube that patented by Vladimir Zworykin in 1923, but was first put into practice in 1926 by Philo T. Farnsworth. The electronic scanning method of the mechanical scanning of the dissolved Ikonoskops Nipkow disc (see also mechanical television).

History

Historical classification

• Vladimir Zworykin ( English spelling of his name ) requested on December 29, 1923 in the United States a patent which was granted on December 20, 1938, U.S. Patent No. 2,141,059.
• Similarities with Philo Farnsworth probe tube led to a lengthy patent dispute.
• This was the basis for the development of advanced image converter.
• The Ikonoskop presented the first electronic basis, which made it possible to transfer directly in the daytime.
• With the Ikonoskop technology in 1937 sat the 441- line standard by officially.
• Together with the cathode ray tube on the receiving side (the actual television tube, also called kinescope ) solved the Iconoscope from the mechanical television.
• The GDR made ​​with the Ikonoskop technology reparations to the Soviet Union.
• The Ikonoskop technique of television cameras was replaced by the orthicon technique.

Olympic Games 1936

The Ikonoskop was referred to in Germany as an image capture and was the camera that was used for the historic television broadcast at the 1936 Olympic Games in Berlin. This camera was developed by Emil Mechau at Telefunken and operated under other by Walter Bruch during the Summer Olympics, where she was then called the " TV " gun. The Ikonoskop was the first mobile television camera in the world. It had a picture resolution of 180 lines and 25 frames / s, the lens has 1.60 m focal length, a lens diameter of 40 cm with a weight of 45 kg and a total length of 2.20 m.

Operation

Small grains photosensitive material (eg, potassium ) are separated by an insulator layer on a metal foil (such as aluminum, see in the picture 34-36). Each of these particles to the metal foil thereby forming a small plate capacitor. If now using lenses ( see in Figure 37 ) an image on the photosensitive side projects, so give the grains depending on the brightness of each pixel electrons, which induces on the metal foil pointwise negative charges.

The metal foil is in a cathode ray tube (see in Figure 27, but also 25/26 and 28-30), in which it is scanned line by line by a beam of electrons. The electrons are repelled to the bright points of the induced charge, but contribute to the dark spots on a current flowing from the aluminum plate to the transmission equipment.

This basic design has been modified slightly to commercial development. Among other things, not the metal foil, but the photosensitive side was scanned.

The mosaic of photosensitive grains compared Zworykin with the realities in the human eye.