FAQs (Frequently Asked Questions)
Q:
What is a USB hub ?
A:
A USB hub provides additional connections to the Universal Serial Bus. A hub's
upstream port connects a hub to the host, usually a PC. Multiple downstream ports in
a hub allows connection to another hub or device, such as a USB keyboard, camera
or printer.
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LCD Panel Technology
Q:
What is a Liquid Crystal Display?
A:
A Liquid Crystal Display (LCD) is an optical device that is commonly used to
display ASCII characters and images on digital items such as watches, calculators,
portable game consoles, etc. LCD is the technology used for displays in notebooks
and other small computers. Like light-emitting diode and gas-plasma technologies,
LCD allows displays to be much thinner than cathode ray tube (CRT) technology.
LCD consumes much less power 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?
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