FAQs (Frequently Asked Questions)
With USB, up to 127 devices can run simultaneously on one computer. USB permits 'hot plug-in.' No
need to shut down, plug in, reboot and run set up to install peripherals. No need to go through the
reverse process to unplug a device. Bottom line: USB transforms today's 'Plug-and-Pray' into true
Plug-and-Play!
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.
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.
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Summary of Contents for 170X4
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