How do projectors work?
There are two types of projectors: The two types of projectors are LCD and DLP.
LCD stands for Liquid Crystal Display. The way this places an image on a screen is fascinating and not nearly as complex as you might imagine. A bulb is set up to shine a fairly powerful light through a prism. The prism splits the light into its component colors and these are sent through small LCD screens. The screens themselves are sent signals to allow just so much of the light through at specific pixel locations. The light is then beamed through a lens onto a screen where the images can be seen by the human eye.
DLP, or Digital Light Processing is a bit more complex. This time the light is shined through a spinning color wheel onto a chip that is mounted with hundreds of thousands of tiny mirrors. The mirrors are turned off or on by electronic impulses according to the need for the color at that moment. Even though only one color is shown at a time, one color follows another so quickly that the primary colors seem to blend into the appropriate color. The image appears to be constantly lit, when in fact small parts of it are constantly flickering. This technology was developed by Texas Instruments and is based on an older technology that was used for color television in the 1950s.
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