Gas Plasma Displays

How does a plasma display work?

Plasma monitors work much like CRT monitors, but instead of using a single CRT surface coated with phosphors, they use a flat, lightweight surface covered with a matrix of tiny glass bubbles, each containing the gas-like substance, plasma, and having a phosphor coating. Each of the "pixels" in this matrix is actually comprised of three sub-pixels, corresponding to the colors red, green and blue.

In a CRT monitor, an electron beam is fired from the rear of the long picture tube, hitting the phosphors on the front surface which makes them glow. Complex circuitry and high voltage deflections coils are required to aim, focus and move the beam to create an entire image.

Plasma displays eliminate the need for high voltage deflection coils and the long neck of a CRT. In a flat plasma monitor, a digitally controlled electric current flows through the appropriate parts of the matrix, causing the plasma inside the bubbles to give off ultraviolet rays. These rays in turn cause the bubbles' phosphor coatings to glow the appropriate color.

Plasma display diagram, courtesy of Fujitsu General America, Inc.