Question

what is cathode ray tube

Answer 1

A high-vacuum tube in which cathode rays produce a luminous image on a fluorescent screen, used in televisions and computer terminals.

Answer 2

The cathode ray tube is a vacuum tube that contains one or more electron guns and a phosphorescent screen, and is used to display images. It modulates, accelerates, and deflects electron beam onto the screen to create the images. 
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