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Related to cathode ray: cathode ray oscilloscope
a stream of electrons emitted by a negative electrode when it is bombarded by positive ions, in a gaseous discharge device called a cathode ray tube. The ray is focused and deflected by electromagnets that control the position at which it strikes a screen coated with a phosphor, creating a visible pattern.
A ray composed of negatively charged electrons discharged by a cathode through a vacuum, moving in a straight line and producing x-ray photons upon hitting solid matter.
See also: ray