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Digital TV / The Coming Resolution

The image you see on your television screen is made up of small rectangular dots called pixels. The word pixel stands for Picture Element, and it's the smallest resolvable rectangular area of an image. Dot Pitch GraphicActually, each pixel is itself composed of three close dots of color: red, green, and blue. Combined together on the phosphor screen, the three separate colors appear to blend into a single color.

Each phosphor emits light in proportion to the intensity of the electron beam hitting it. On a standard television screen, the electron beam has about 256 levels of intensity for each of the three colored phosphors. Therefore, each pixel has a spectral range of about 16.8 million colors. Ideally, the three phosphors would be in exactly the same spot, but they're only close enough together to fool your eyes into thinking they are.

From a distance, each pixel ends up looking like a single dot of color. If you look up close, though, you'll see that each pixel is really a rectangular trio of red, green, and blue. You can really see it on a projection television when the colors separate a little more. The resolution on current television isn't very good. To improve the resolution, HDTV is going to use smaller pixels that are closer together, and they're going to be square.

Hip To Be Square[next]


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