Plasma

Understanding plasma technology

A plasma TV is a very thin television that doesn’t use a vacuum tube to produce the image on the screen. Cathode ray tubes found in CRT televisions use vacuum tubes and are bulky and heavy. The reason for this is that the larger the size of the screen, the deeper the tube needs to be for the electron gun to reach all parts of the screen. The plasma monitor is much thinner for an equal size of television screen. A plasma display illuminates tiny fluorescent lights to create the image. Every pixel contains 3 colors: red, blue and green. The intensity of the colors varies in order to create the range of colors on the plasma screen.

How Plasmas Work

A Panasonic plasma TV uses xenon and neon gas compressed into tiny cells sandwiched between two glass plates. Two sets of electrodes are positioned on either side of the cells filled with the gas. One set of electrodes is positioned horizontally and the other set is positioned vertically. This creates a series of rows and columns. When a certain cell is to be turned on, an electrical charge is sent through the cells, and the pixel where the electrodes intersect is activated. This turning on and off of cells happens thousands of times in a fraction of a second. When the electrical charge passes through the cell and ionizes the gas it produces ultraviolet light. Coating the inside of the cell is a phosphorous material, which heats up and becomes visible light when hit with the ultraviolet light from the ionized gas.

The technology used in plasma TVs produces a very bright and clear picture. It can have a much wider viewing screen than an LCD. Plasma HDTVs are much more expensive than standard plasma. The difference is that there are more pixels crammed into the same amount of space, resulting in more screen resolution and better picture quality. Often HDTVs will be equipped with 5.1 Dolby surround sound which allows the user to have a much more enriching sound.

Different manufacturers use different frame rates to change the image on the screen. The frame rate is the number of times per second the screen is refreshed and this can be anywhere from 25 to 60 frames per second. When choosing a plasma TV, choose one under good lighting and with different, high intensity coloring to get a good feel of what one model looks like compared to another.