CertiGuide to A+ (Core Hardware)  9  Chapter 1000:  Multimedia       9  IV  Monitors

Refresh Rate 1 Pop Quiz 1000.00

The component in the monitor that is responsible for creating the images you see is called a Cathode Ray Tube, or CRT.

The digital signals are sent from the video card as three sets of varying voltages.

The signals are then sent to three different electron guns that are mounted on the back end of the CRT. By varying the voltages in each one of the signals, each electron gun can vary its intensity.

The display end of the CRT is coated with three types of phosphors that glow red, green, or blue.

The three electron beams pass over the phosphorus material causing them to glow.

The number of times the electron beams pass over the front of the CRT is the refresh rate.

Some inexpensive monitors use a technique known as interlacing.

Here each electron beam only strikes every other row of phosphors during a pass.

These monitors can be quite annoying to work at, as they tend to flicker.

Because the phosphors are only passed over at half the rate of a non-interlaced monitor, they lose a lot of their intensity before being refreshed, causing the appearance of flickering.

Refresh Rate 1 Pop Quiz 1000.00