High-voltage cathode-ray tube (CRT) displays, such as those used in older television sets and computer monitors, typically require voltages in the range of thousands of volts to operate properly. The specific voltage requirement can vary depending on the size and design of the CRT, as well as the intended application.
For example, a common CRT television might require an anode voltage (also known as acceleration voltage or high voltage) of around 20,000 to 30,000 volts. Computer monitors with CRT displays might have similar voltage requirements. Keep in mind that these voltages are high and potentially dangerous, requiring appropriate safety measures and equipment when working with them.
The high voltage is used to accelerate the electrons emitted by the cathode towards the screen, allowing them to create the visual image by interacting with phosphorescent materials on the screen's surface. The CRT also includes various other voltages for controlling the electron beams and the various components of the display.
It's important to note that CRT technology has largely been phased out in favor of modern display technologies such as LCDs, OLEDs, and other flat-panel displays, which have lower power consumption, are thinner, and offer better image quality.