![]() In every monitor device, the entire front area of the tube is scanned repetitively and systematically in a fixed pattern called a raster. The electron beam produces a tiny, bright visible spot when it strikes the phosphor-coated screen. CRT has three electron beams – one for each (Red, Green, and Blue) is clearly shown in the figure. A cathode-ray tube consists of one or more electron guns, possibly internal electrostatic deflection plates, and a phosphor target. The operation of a CRT monitor is very simple. Usually, A CRT has a fluorescent screen to display the output signal. The source of the electron beam is the electron gun the gun is located in the narrow, cylindrical neck at the extreme rear of a CRT which produces a stream of electrons through thermionic emission. The working of CRT depends on the movement of an electron beam which moves back and forth across the back of the screen. This screen is coated with phosphor, which glows when struck by the beam.Ĭathode Ray Tube (CRT) is a computer display screen, used to display the output in a standard composite video signal. This tight, high-speed beam of electrons flies through the vacuum in the tube and hits the flat screen at the other end of the tube. In a TV’s cathode ray tube, the stream of electrons is focused by a focusing anode into a tight beam and then accelerated by an accelerating anode. The anode is positive, so it attracts the electrons pouring off the cathode. The ray is a stream of electrons that naturally pour off a heated cathode into the vacuum. In a cathode ray tube, the cathode is a heated filament and it placed in a vacuum. And also when the external magnetic field is reversed, the beam of electronics is deflected in the opposite direction. The electrons deflected by the magnetic field. A moving charged body behaves like a tiny magnet, and it can interact with an external magnetic field. Therefore a cathode ray must consist of negatively charged particles. When an electric field is applied across the cathode ray tube, the cathode ray is attracted by the plate bearing positive charges. When the ray strikes the specially coated surface, the cathode ray produces a strong fluorescence or bright light. The cathode ray is drawn to the positively charged plate, called the anode, where it passes through a hole and continues traveling to the other end of the tube. When the two metal plates are connected to a high voltage source, the negatively charged plate called the cathode emits an invisible ray.
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