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Phototube. A phototube or photoelectric cell is a type of gas-filled or vacuum tube that is sensitive to light. Such a tube is more correctly called a 'photoemissive cell' to distinguish it from photovoltaic or photoconductive cells. Phototubes were previously more widely used but are now replaced in many applications by solid state photodetectors.
A vacuum tube, electron tube, [ 1][ 2][ 3] valve (British usage), or tube (North America) [ 4] is a device that controls electric current flow in a high vacuum between electrodes to which an electric potential difference has been applied. The type known as a thermionic tube or thermionic valve utilizes thermionic emission of electrons from a ...
Photomultiplier tubes ( photomultipliers or PMTs for short) are extremely sensitive detectors of light in the ultraviolet, visible, and near-infrared ranges of the electromagnetic spectrum. They are members of the class of vacuum tubes, more specifically vacuum phototubes. These detectors multiply the current produced by incident light by as ...
YD1336 – 1.8 kW, Air-cooled, UHF power triode. YD1342 – 30 MHz, 530 kW, Water-cooled RF power triode. YD1352S (8867, DX334) – 5 MHz, 2 kW, Water-cooled Neotron, a gridless field-effect tube where a magnetically focused electron beam is modulated by varying the voltage of a gate electrode surrounding it.
A vacuum-tube computer, now termed a first-generation computer, is a computer that uses vacuum tubes for logic circuitry. While the history of mechanical aids to computation goes back centuries, if not millennia, the history of vacuum tube computers is confined to the middle of the 20th century. Lee De Forest invented the triode in 1906.
Video camera tube. A display of numerous video camera tubes from the 1930s and 1940s, photographed in 1954, with iconoscope inventor Vladimir K. Zworykin. Video camera tubes were devices based on the cathode-ray tube that were used in television cameras to capture television images, prior to the introduction of charge-coupled device (CCD) image ...
Photocathodes operate in a vacuum, so their design parallels vacuum tube technology. Since most cathodes are sensitive to air the construction of photocathodes typically occurs after the enclosure has been evacuated. In operation the photocathode requires an electric field with a nearby positive anode to assure electron emission.
Atanasoff contemplated storing the coefficients of an equation in capacitors located on the periphery of a cylinder. He apparently had a prototype of his machine working "early in 1940". This machine was, it should be emphasized, probably the first use of vacuum tubes to do digital computation and was a special-purpose machine.