FAQs (Frequently Asked Questions)
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 and
attached, respectively. The TFT drain of each cell is connected to the electrode. The
molecular arrangement of liquid crystal elements differs 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.
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 in 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
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