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?
A: Technically speaking, LCDs do flicker, but the cause of the phenomenon is different from
that of a CRT monitor -- and it has no impact of the ease of viewing. Flickering in an LCD
monitor relates to usually undetectable luminance caused by the difference between
positive and negative voltage. On the other hand, CRT flickering that can irritate the human
eye occurs when the on/off action of the fluorescent object becomes visible. Since the
reaction speed of liquid crystal in an LCD panel is much slower, this troublesome form of
flickering is not present in an LCD display.
Q: Why is an LCD monitor virtually free of Electro Magnetic Interference?
A: Unlike a CRT, an LCD monitor does not have key parts that generate Electro Magnetic
Interference, especially magnetic fields. Also, since an LCD display utilizes relatively low
power, its power supply is extremely quiet.
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Ergonomics, Ecology and Safety Standards
Q:
What is the CE mark?
A: The CE (Conformité Européenne) mark is required to be displayed on all regulated
products offered for sale on the European market. This 'CE' mark means that a product
complies with the relevant European Directive. A European Directive is a European 'Law'
that relates to health, safety, environment and consumer protection, much the same as the U.
S. National Electrical Code and UL Standards.
More information is provided in the Regulatory Information section.
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