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LCD
- How it Works.
An LCD TV is sometimes referred to as a "transmissive"
display — light isn't created by the liquid crystals themselves;
a light source (bulb) behind the panel shines light through the
display. A white diffusion panel behind the LCD redirects and scatters
the light evenly to ensure a uniform image.
The
display consists of two polarizing transparent panels and a liquid
crystal solution sandwiched in between. The screen's front layer
of glass is etched on the inside surface in a grid pattern to form
a template for the layer of liquid crystals. Liquid crystals are
rod-shaped molecules that bend light in response to an electric
current — the crystals align so that light cannot pass through
them. Each crystal acts like a shutter, either allowing light to
pass through or blocking the light. The pattern of transparent and
dark crystals forms the image. It's the same display technology
behind your digital watch but way more sophisticated.

The multi-layered structure of an active-matrix LCD panel. Because
they use red, green and blue color filters in place of phosphor
dots, LCD panels are completely immune to image burn-in.
LCD
TVs use the most advanced type of LCD, known as an "active-matrix"
LCD. This design is based on thin film transistors (TFT) —
basically, tiny switching transistors and capacitors that are arranged
in a matrix on a glass substrate. Their job is to rapidly switch
the LCD's pixels on and off. In a color TV's LCD, each color pixel
is created by three sub-pixels with red, green and blue color filters.
One
of the biggest challenges for LCD TV manufacturers has been speeding
up the "pixel response" time (how fast an individual pixel's
color can change without blurring) to ensure that fast-moving objects
don't exhibit "motion lag" or ghosting. It's especially
critical for larger-screen LCD TVs where much of the viewing will
be DVD movies and/or HDTV.
An
important difference between plasma and LCD technology is that an
LCD screen doesn't have a coating of phosphor dots (colors are created
through the use of filters). That means you'll never have to worry
about image burn-in, which is great news, especially for anyone
planning to connect a PC or video game system. LCD TVs are extremely
energy-efficient, typically consuming 60% less power than comparably-sized
tube-type direct-view TVs!
For
more information on TV resolutions Click
Here
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