Glossary of Terms
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Data Video Projector
User Manual
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Glossary of Terms
Hz, KHz, MHz (Hertz, Kilohertz, Megahertz)
Hertz is a unit of measurement used to express the frequency, in cycles per second, of
an electrical signal or event. (Megahertz = 1 million cycles per second)
Lumens
A measure of light output on a screen or other surface. One lumen is the light of one can-
dle power on each square foot of a surface of a sphere at a radius of one foot from the
light source.
Metal halide lamp
A modified mercury arc lamp that is extremely bright. It is filled with a gas with elements
known as halogens. The properties of this fill gas allows the lamp to burn longer and
brighter than ordinary lamps.
NTSC (National Television Systems Committee)
Standard for television signals and other video equipment signals. The standard uses in-
terlaced scans and 525 horizontal lines per frame, at a rate of 30 frames per second.
PAL (Phase Alternate Line)
The format for colour television signals used in Germany, England and many other coun-
tries. PAL is an interlaced format with 25 frames per second and 625 lines per screen.
Pixel (word coined from Picture Element)
This is one image dot, a definite position on a display that consists of a single dot or a
group of three dots (red, green, blue).
Resolution
The number of pixels available in a display device for creating images. Expressed as a
number of columns by number of rows (e.g. SVGA resolution, 800 x600).
S-VHS (S-Video, Super VHS)
A video signal which separates the luminance (Y) and chrominance (C) signals. Also
known as Y/C video.
SECAM (Séquentiel Couleur a Mémoire)
A colour television standard developed in France and also used in certain other countries.
XGA
A standard PC computer analogue interface: resolution of 1024 x 768.