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bottom. When impressed with voltage, liquid crystal molecules are
arranged vertically from the original spiral structure and the
direction of the light is not turned through 90 degrees. In this case,
light that comes through the top polarized panel may not go through
the polarized panel at the bottom.
Q: What are the advantages of TFT LCD compared with CRT?
A: In a CRT monitor, a gun shoots electrons and general light by
colliding polarized electrons on fluorescent glass. Therefore, CRT
monitors basically operate with an analog RGB signal. A TFT LCD
monitor is a device that displays an input image by operating a liquid
crystal panel. The TFT has a fundamentally different structure than a
CRT: Each cell has an active matrix structure and independent active
elements. A TFT LCD has two glass panels and the space between
them is filled with liquid crystal. When each cell is connected with
electrodes and impressed with voltage, the molecular structure of
the liquid crystal is altered and controls the amount of inlet lighting
to display images. A TFT LCD has several advantages over a CRT,
since it can be very thin and no flickering occurs because it does not
use the scanning method.
Q: Why is vertical frequency of 60Hz optimal for an LCD monitor?
A: Unlike a CDT monitor, the TFT LCD panel has a fixed resolution.
For example, an XGA monitor has 1024x3 (R, G, B) x 768 pixels and
a higher resolution may not be available without additional software
processing. The panel is designed to optimize the display for a
65MHz dot clock, one of the standards for XGA displays. Since the
vertical/horizontal frequency for this dot clock is 60Hz/48kHz, the
optimum frequency for this monitor is 60Hz.
Q: What kind of wide-angle technology is available? How does it work?
A: The TFT LCD panel is an element that controls/displays the inlet
of a backlight using the dual-refraction of a liquid crystal. Using the
property that the projection of inlet light refracts toward the major
axis of the liquid element, it controls the direction of inlet light and
displays it. Since the refraction ratio of inlet light on liquid crystal
varies with the inlet angle of the light, the viewing angle of a TFT is
much narrower than that of a CDT. Usually, the viewing angle refers
to the point where the contrast ration is 10. Many ways to widen the
viewing angle are currently being developed and the most common
approach is to use a wide viewing angle film, which widens the
viewing angle by varying the refraction ratio. IPS (In Plane Switching)
or MVA (Multi Vertical Aligned) is also used to give a wider viewing
angle.
Q: Why is there no flicker on an LCD Monitor?
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User Manual 190S6FGT
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