Decoded: Digital Light Processing (DLP)
DLP technology has slashed the cost of projectors from hundreds to tens of thousands of rupees.
Digital Light Processing or DLP was developed by Dr. Larry Hornbeck -- who worked for Texas Instruments at the time -- in 1987. The technology is based on an optical semiconductor called the Digital Micromirror Device (DMD,) which enables light to be modulated digitally with the help of a cluster of microscopic mirrors. Each one of these mirrors usually represents a single pixel on a screen.
When a signal enters the technology, it causes each of these microscopic mirrors to reflect a light source through a projection lens and onto a screen. The video out from these mirrors are different shades of grey. In most cases, colour is added to these monochrome images using a colour wheel. The wheel is placed between the light reflected from the mirrors and the digital micromirror device. When all these components come together they reproduce a color video image on the display surface.
Even though the technology was demonstrated in 1987, the first commercial DLP projector was introduced only ten years later by Digital Projection Ltd.
Apart from its application in home and commercial projectors, DLP is also used in television sets, digital signs and in about 85 percent of digital cinema projection systems.