FAQs (Frequently Asked Questions)
than LED and gas-displays because it works on the principle of blocking light rather than
emitting it.
Q:
How are LCDs made?
A:
LCDs are created from two glass plates separated from each other at a distance of a few
microns. The plates are filled with liquid crystal and then sealed together. The top plate is
colored with an RGB pattern to make the color filter. Polarizers are then glued to both plates.
This combination is sometimes called 'glass' or 'cell.' The LCD cell is assembled into a
'module' by adding the backlight, driver electronics and frame.
Q:
What is polarization ?
A:
Polarization is basically directing light to shine in one direction. Light is electromagnetic
waves. Electric and magnetic fields oscillate in a direction perpendicular to the propagation
of the light beam. The direction of these fields is called the 'polarization direction'. Normal or
non-polarized light has fields in several directions; polarized light has a field in only one
direction.
Q:
What differentiates passive matrix LCDs from active matrix LCDs?
A:
An LCD is made with either a passive matrix or an active matrix display grid. An active
matrix has a transistor located at each pixel intersection, requiring less current to control
the luminance of a pixel. For this reason, the current in an active matrix display can be
switched on and off more frequently, improving the screen refresh time (your mouse pointer
will appear to move more smoothly across the screen, for example). The passive matrix LCD
has a grid of conductors with pixels located at each intersection in the grid.
Q:
How does a TFT LCD Panel work?
A:
On each column and row of the TFT LCD panel, a data source drive and a gate drive are
attached, respectively. The TFT drain of each cell is connected to the electrode. The
molecular arrangement of liquid crystal elements differ according to whether it is impressed
with voltage or not. It varies the direction of polarized light and the amount of light by letting
it through different arrays of liquid crystal elements. When two polarized filters are arranged
vertically on a polarized light pole, the light that passes through the upper polarized panel is
turned 90 degrees along with the spiral structure of the liquid crystal molecules and goes
through the polarized filter at the 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.
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