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.
RETURN TO TOP OF THE PAGE
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
file:///D|/My%20Documents/dfu/150E6FB/ENGLISH/150e6/SAFETY/saf_faq.htm (5 of 8)2005-05-27 9:26:41 AM
