Glossary
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Interlaced
A method of image scanning whereby the lines in a single image are divided into two sections
or "fields". The signal bandwidth used for interlaced scanning is approximately half that
required for progressive scanning when images with the same still picture resolution are
broadcast.
Offset
The adjustment of minute changes in color that occur as result of factors such as differences
in the equipment used to display images. It adjusts the coloration in darker ranges separately
for R, G and B components.
Refresh Rate
The light-emitting element of a display maintains the same luminosity and color for an
extremely short time. Because of this, the image must be scanned many times per second in
order to refresh the light emitting element. The number of refresh operations per second is
called the "refresh rate", and is expressed in hertz (Hz).
S-Video images
A video signal which has the luminance component and color component separated in order
to provide better image quality.
It refers to images which consist of two independent signals: Y (luminance signal), and C
(color signal).
SDTV
An abbreviation for Standard Definition Television. It refers to standard television systems
which do not satisfy the conditions for High-Definition Television.
sRGB
An international standard for color intervals that was formulated so that colors which are
reproduced by video equipment can be handled easily by computer operating systems (OS)
and the Internet.
SVGA
A type of image signal with a resolution of 800 (horizontal) x 600 (vertical) dots which is
used by IBM PC/AT-compatible computers (DOS/V computers).
SXGA
A type of image signal with a resolution of 1280 (horizontal) x 1024 (vertical) dots which is
used by IBM PC/AT-compatible computers (DOS/V computers).
Synchronization
(Sync.)
The signals output from computers have a specific frequency. If the projector frequency does
not match this frequency, the resulting images will not be of a good quality. The process of
matching the phases of these signals (the relative position of the crests and troughs in the
signal) is called "synchronization". If the signals are not synchronized, problems such as
flickering, blurriness and horizontal interference can occur.
Tracking
The signals output from computers have a specific frequency. If the projector frequency does
not match this frequency, the resulting images will not be of a good quality. The process of
matching the frequency of these signals (the number of crests in the signal) is called
“tracking”. If tracking is not carried out correctly, wide vertical stripes will appear in the
projected images.
UXGA
A type of image signal with a resolution of 1600 (horizontal) x 1200 (vertical) dots which is
used by IBM PC/AT-compatible computers (DOS/V computers).
VGA
A type of image signal with a resolution of 640 (horizontal) x 480 (vertical) dots which is
used by IBM PC/AT-compatible computers (DOS/V computers).
XGA
A type of image signal with a resolution of 1,024 (horizontal) x 768 (vertical) dots which is
used by IBM PC/AT-compatible computers (DOS/V computers).
