CRO full form is Cathode Ray Oscilloscope, is a very fast X-Y plotter that can display an input signal versus time or another signal.An electrical test device called a cathode ray oscilloscope is used to produce waveforms in response to several input signals. It was originally known as an oscillograph.

The heater of the electron gun generates the electron beam using low voltage. The cathode ray tube needs a high voltage to accelerate the beam. Other oscilloscope control units require the standard voltage supply. In between electron gun and the screen are placed between the horizontal and vertical plates, allowing it to detect the beam in accordance with the input signal, and display it on the screen.

The CRO oscilloscope's time base generator produces the blanking voltage. This additional focusing control in CRO is comparable to astigmatism in optical lenses. Due to the different lengths of the electron pathways at the center and the corners of the screen, a beam that is focused in the monitor's middle would be defocused here

General controls, time base controls, Horizontal and vertical controls, trigger controls

Phosphor crystals are used to cover the inside face of the faceplate and convert electrical energy into light. This phenomenon is known as fluorescence it occurs when an electronic ray strikes the phosphor crystal.