cathode-ray beam
Quick Summary
A cathode ray is a stream of electrons originating from a negative electrode (cathode) in a low-pressure discharge tube or emitted from a heated filament in certain electron tubes. When these rays strike a screen coated with specific molecules, they cause it to emit light. This light-producing effect, combined with the ability to control the electron beam's direction using electric or magnetic fields, is the basis for technologies like the cathode-ray tube (CRT). CRTs are vacuum tubes that generate images by directing electron beams onto a phosphor-coated screen, causing it to glow. This technology was fundamental to early televisions and radar systems.1234
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