Hughes JVC 200, Service Manual

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Glossary
Glossary Of Terms
Amorphous Without definite form; not crystallized.
Arc Lamp The xenon arc lamp in the Model 200 projector. It
operates at high temperatures (160° to 200°) and
produces dangerously intensive light with
hazardous levels of ultraviolet and infrared
radiation.
Aspect Ratio The ratio of the picture width to picture height.
The standard U.S. television aspect ratio is four
units wide to three units high (4:3). High Definition
Television (HDTV) is 16:9.
Bandwidth The transmission or reception capacity of a
computer or communications channel measured
in bits per second in digital and in Hertz in
communications. Bandwidth is the difference
between the lowest and highest frequencies
transmitted or received. Wider bandwidth
provides more information or picture detail
capability.
Chrominance Abbreviated as "C." Color information signal or
signals.
Cold Mirror Mirror that absorbs infrared light so that its
reflection contains only "cold' light that does not
transmit appreciable heat. As a result of this
absorption of infrared heat radiation, "cold"
mirrors get quite hot.
CRT (Cathode Ray Tube) The vacuum tube used as a display screen in
video terminals or television sets. Commonly
called the picture tube.
Dichroic Mirrors The white light of the xenon arc lamp is separated
into red, green and blue by means of
dichroic
mirrors which reflect only one color and pass all
others.
Field One half of a complete video frame. Odd lines in
one field and even lines in another make up one
frame.
Frame One complete TV picture or screen of
information. It is composed of two fields and has
Model 200 Service Manual B-1