LG 42LB4D, Руководство по обучению

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Directview LCD Training
10
Theory
TheOry
TFT Element
Pixel Electrode
(Transparent)
Insulator
Semi-conductor
Source
Gate
Drain
Glass Panel
Data Line
Gate Line
Pixel Electrode
Liquid Crystal
Common Electrode
Color Filter
Polarizer
Polarizer
Transistor
lIquId CRYSTAl PANEl
Below (on the left) is a cross section of a liquid crystal panel. The key to an LCD’s operation is the
polarizers. The polarizers only allow a certain wavelength of light to pass through. The two polarizers
are mounted at a 90 degree angle with respect to each other, which prevents light from passing through.
The liquid crystals are used to twist the light beam 90 degrees and allow light to pass through that
cell. Color comes from a simple light filter.
Each sub-pixel or cell (a red, green, and blue sub-pixel equals one
pixel) is controlled by a Thin Film Transistor (TFT). This provides
accurate control of each cell and makes for an accurate picture.
Some methods used in the past that didn’t involve a switch and
current could leak to surrounding cells resulting in a blurred image.
A TFT is a semiconductor (bottom-right picture), it behaves like a
relay switch.