Q: What is USB (Universal Serial Bus)?
A: Think of USB as a smart plug for PC peripherals. USB automatically determines resources (like
driver software and bus bandwidth) required by peripherals. USB makes necessary resources
available without user intervention. There are three main benefits of USB. USB eliminates "case
angst," the fear of removing the computer case to install circuit board cards -- that often require
adjustment of complicated IRQ settings -- for add-on peripherals. USB does away with "port
gridlock." Without USB, PCs are normally limited to one printer, two Com port devices (usually a
mouse and modem), one Enhanced Parallel Port add-on (scanner or video camera, for example), and
a joystick. More and more peripherals for multimedia computers come on the market every day.
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.
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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-display 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 coloured
with an RGB pattern to make the colour 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.
FAQs (Frequently Asked Questions)
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