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Glossary
Glossary
Complex terms used in this book, or terms not explained in the body of the
text, will be briefly explained here. For further explanation, please consult
commercially available reference texts.
5BNC A type of connector used to input analog video
signals.
Aspect ratio The ratio between an image’s length and its height.
Images which have an aspect ratio of 16:9 are called
Widescreen. The aspect ratio for standard images is
4:3.
Color
Temperature The temperature of an object which is emitting light.
When the color temperature is high, colors tend to
take on a bluish tinge; when the color temperature is
low, colors tend to take on a reddish tinge.
Component Video A type of video signal which has the video
brightness and color signal information separated, in
order to provide better image quality. In high-
definition TV (HDTV), it refers to images which
consist of three independent signals: Y (luminance
signal), and Pb and Pr (color difference signals).
Composite Video The standard home video signal (NTSC, PAL,
SECAM) which has the video brightness and color
signal information mixed together. Composite video
consists of the carrier signal Y (luminance signal)
and the chroma (color) signal, combined within the
color bar signal.
Contrast The relative brightness of the light and dark areas of
an image, which can be increased or decreased in
order to make text and graphics stand out, or appear
softer.
Cool-down The process used to cool down a projector lamp that
is hot from use. Cool-down happens automatically
when the [Power] button is pressed on the projector
or on the remote control to turn the projector off. Do
not unplug the projector power cable while it is
cooling down. If cool-down is interrupted, heat from
the lamp gets trapped inside the projector,
potentially shortening the life of the lamp and
causing projector failure.
Dolby
digital An audio format developed by Dolby Laboratories.
Normal stereo is a 2-channel format which uses two
speakers, whereas Dolby Digital is a 6-channel (5.1-
channel) system which adds a center speaker, two
rear speakers and a sub-woofer.
HDTV An abbreviation for High-Definition Television, it
refers to high definition systems which satisfy the
following conditions:
• Vertical resolution of 750p or 1125i or greater
(p=Progressive scanningg, i=Interlaced scanningg)
• Screen aspect ratio of 16:9
• Dolby digitalgl audio reception and playback (or
output)
Interlaced
scanning Each screen is divided into fine horizontal lines
which are displayed in sequence starting from left to
right and then from top to bottom. In this method of
image scanning, even numbered lines and odd
numbered lines are displayed alternately.
Progressive
scanning A method of image scanning whereby the image
data from a single image is scanned sequentially
from top to bottom to create a single image.