DLP televisions are based on a technology invented
by Texas Instruments back in 1987 called Digital
Light Processing. The technology is based on
an optical semiconductor called DMD (Digital
Micromirror Device) chip. It is a highly reliable,
all-digital display chip that delivers the best
picture across a broad range of products, including
large screen digital TVs, and projectors for
business, home, professional venue and digital
cinema.
The chip consists of over one million mirrors
to process light. They come in either single
chip or 3 chip configurations. One-chip DLP
systems use a projection lamp to pass white
light through a color wheel that sends red-green-blue
colors to the DMD chip in a sequential order
to create an image on-screen. Only one DMD chip
is used to process the primary RGB colors. Three-chip
DLP systems use a projection lamp to send white
light through a prism, which creates separate
red, green, and blue light beams. Each beam
is sent to their respective red, green, and
blue DMD chip to process the image for display
on-screen. One-chip models are said to produce
a display of over 16-million colors. Three-chip
models can produce a display of over 35-trillion
colors. The result is maximum fidelity: a picture
whose clarity, brilliance and color must be
seen to be believed.
When a DLP chip is coordinated with a digital
video or graphic signal, a light source, and
a projection lens, its mirrors can reflect an
all-digital image onto a screen or other surface.
The DLP chip and the sophisticated electronics
that surround it are what we call Digital Light
ProcessingT technology.
Benefits of Single chip DLP:
1. Fantastic color accuracy.
2. The best contrast ratios and shadow detail.
3. Generally very quiet.
4. Very little space between each pixel creates
a very smooth image, even when using lower resolution
projectors.
5. Light engine failures are very rare so repairs
are less costly than other technologies.
6. Technology doesn't degrade over time. With
proper routine maintenance, DLPT projectors
consistently provide just-out-of-the-box performance.
(DLPT is the only technology that makes this
claim).
Benefits of Three chip DLP:
1. Good contrast; much greater than film theaters.
2. Good shadow detail.
3. Can provide high brightness compared to
the limited brightness of single chip versions.
4. Overall image quality deemed as the best
of any type of micro display technology.
5. Same technology as projectors installed
in digital theaters.
6. Pure digital technology.
The bit-streamed image code entering the semiconductor
directs each mirror to switch on and off up
to several thousand times per second. When a
mirror is switched on more frequently than off,
it reflects a light gray pixel; a mirror that's
switched off more frequently reflects a darker
gray pixel. In this way, the mirrors in a DLP
projection system can reflect pixels in up to
1,024 shades of gray to convert the video or
graphic signal entering the DLP chip into a
highly detailed grayscale image.
The white light generated by the lamp in a
DLP projection system passes through a color
wheel as it travels to the surface of the DLP
chip. The color wheel filters the light into
red, green, and blue, from which a single-chip
DLP projection system can create at least 16.7
million colors. And the 3-chip system found
in DLP CinemaT projection systems is capable
of producing no fewer than 35 trillion colors.
The on and off states of each micromirror are
coordinated with these three basic building
blocks of color. For example, a mirror responsible
for projecting a purple pixel will only reflect
red and blue light to the projection surface;
our eyes then blend these rapidly alternating
flashes to see the intended hue in a projected
image.
| About The Author
Mitchell Medford is an author and product
consultant for several consumer electronics
manufacturers. Visit his website for more
information on home theater, LCD TVs,
and plasma televisions: http://www.newtechnologytv.com
|
This article was posted on November 13,
2005