Digital Light Processing Television

Based on TI Info., "DLP^TM stands for Digital Light Processing. DLP^TM technology was invented by Dr. Larry Hornbeck of Texas Instruments in 1987. It's a projection/display technology that's used in large-screen TVs, business projectors, home theater/home cinema projectors, video walls, conference room projectors and movie theaters. It can be considered an alternative projection/display technology to CRT (Cathode Ray Tube), LCD (Liquid Crystal Display) and plasma. The first products to feature DLP^TM technology were shipped in early 1996.

At the heart of DLP^? technology is an amazing semiconductor: the Digital Micromirror Device, or DMD.

The principle of the DMD is very simple. It uses an array of microscopically small, square, hinged mirrors each of which acts as a light switch. One mirror corresponds to one pixel in the projected image?so in a large-screen TV, there would typically be 1,280 x 720 individual mirrors.

Under opposite corners of each mirror are electrodes that cause the mirror to tilt 12 degrees in either direction. (As each mirror has only two states-12 degrees in one direction or 12 degrees in the other-DLP^TM technology can truly be said to be a digital technology.) The electrodes are activated by the graphics or video signal in the underlying memory chip. Tilting the mirror in the "on" direction causes light from a lamp to be reflected out through a lens and on to the screen, where it appears as a white pixel. Tilting the mirror in the "off" direction causes no light to be passed through the lens and on to the screen, resulting in a black pixel in the corresponding position on the screen.

Shades of gray are created by varying the proportion of time a mirror is on or off. Each mirror can switch on and off up to 5,000 times per second; the human eye integrates this and does not see the individual switching movements. Thus, a light grey pixel is produced by increasing the proportion of time a mirror is on relative to its off time, and a dark grey pixel by increasing the proportion of time the mirror is off relative to its on time.

In a simple projection system, such as in a large screen TV, only a single DMD is used. Color is created by placing a rapidly rotating color filter wheel between the lamp and the surface of the DMD. Now, instead of white light falling on the surface of the mirrors, red, green and blue lights shine sequentially on them. Up to 16 million colors can be created by varying the proportion of time a mirror is reflecting red, green or blue light.

Thus, to create a purple pixel: The mirror "responsible" for that pixel would be switched "on" when red light is shining on it and also "on" when blue light is shining on it. The human eye integrates the rapid switching of the red and blue light and sees only a purple pixel.

Higher Contrast: The simpler optical system reduces the unwanted effect of "stray" light, allowing for better contrast ratios, which means sharper, more detailed images.

Sharper: The unique single-panel design of DLP^TM technology means that the onscreen image is always precisely converged, without the misalignment that can occur with three-panel technologies.

Better Motion Reproduction: Pixel switching speeds in DLP^TM technology are faster, allowing more accurate reproduction of fast-moving action without blur, smear or ghosting.

More Film-like Images: The high "fill factor" of DLP^TM technology creates images that are smoother and more film-like, compared with technologies where individual pixels in the image are clearly visible, creating a "screen door" effect.

Digital: DLP^TM technology is digital, as opposed to analog, so images are reproduced more accurately and performance is not affected by environmental factors.

Reflective: DLP^TM technology is reflective, as opposed to transmissive, which means that it is less susceptible to degradation caused by the absorption of light and heat.

At larger screen sizes, TVs based on DLP^TM technology are much more affordable, yet are slim, lightweight and visually attractive. DLP^TM technology also offers superior picture quality; lower power consumption; no phosphor "burn-in"; and a longer product lifetime.

Almost every television manufacturers are using DLP^TM technology to apply to their products, such as Hitachi, Mitsubishi, Sony, Pioneer, Sharp, Dell, InFocus, Panasonic, Viewsonic, Zenith, NEC, RCA, Samsung, Toshiba, Philips, JVC.

Let's see how the DLP^TM astonishingly works. Here is the DLP demo (requires Flash application)

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