Search results
Results From The WOW.Com Content Network
A cathode-ray tube (CRT) is a vacuum tube containing one or more electron guns, which emit electron beams that are manipulated to display images on a phosphorescent screen. [2] The images may represent electrical waveforms on an oscilloscope , a frame of video on an analog television set (TV), digital raster graphics on a computer monitor , or ...
In 1906, Lee De Forest found that a small voltage on a grid of metal wires between the cathode and anode could control a current in a beam of cathode rays passing through a vacuum tube. His invention, called the triode , was the first device that could amplify electric signals, and revolutionized electrical technology, creating the new field of ...
Before the introduction of the CRO in its current form, the cathode ray tube had already been in use as a measuring device. The cathode ray tube is an evacuated glass envelope, similar to that in a black-and-white television set, with its flat face covered in a fluorescent material (the phosphor). The screen is typically less than 20 cm in ...
Electron gun from an oscilloscope CRT Setup of an electron gun. 1. Hot cathode.2. Wehnelt cylinder.3. Anode. A direct current, electrostatic thermionic electron gun is formed from several parts: a hot cathode, which is heated to create a stream of electrons via thermionic emission; electrodes generating an electric field to focus the electron beam (such as a Wehnelt cylinder); and one or more ...
Flying-spot scanner technology was later implemented by DuMont Laboratories in the Vitascan color television system, released in 1956. Vitascan produced NTSC color video using a camera that acted in reverse by housing the flying-spot CRT which was projected through the camera's lens and illuminated the subject in a special light-tight studio.
A teltron tube (named for Teltron Inc., which is now owned by 3B Scientific Ltd.) is a type of cathode-ray tube used to demonstrate the properties of electrons. There were several different types made by Teltron including a diode, a triode, a Maltese Cross tube, a simple deflection tube with a fluorescent screen, and one which could be used to ...
In 1899 Jonathan Zenneck equipped the cathode ray tube with beam-forming plates and used a magnetic field for sweeping the trace. [ 15 ] Early cathode ray tubes had been applied experimentally to laboratory measurements as early as 1919 [ 16 ] but suffered from poor stability of the vacuum and the cathode emitters.
The following table compares cathode-ray tube (CRT), liquid-crystal display (LCD), plasma and organic light-emitting diode (OLED) display device technologies. These are the most often used technologies for television and computer displays.