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Appendix
Glossary
Following is an explanation of some of the terms used in this guide which may be unfamiliar or which 
were not explained in the manual itself. Further information can be obtained by referring to other 
commercially-available publications.
 
Aspect
The ratio between an image's length and its height. 
HDTV  images have an aspect of 16:9 and appear 
elongated. The aspect for standard images is 4:3.
Component video
Video signals which have the video brightness signals 
and color signals 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
Video signals which have the video brightness signals 
and color signals mixed together. The type of signals 
commonly used by household video equipment 
(NTSC , PAL  and SECAM  formats).
Video signals which consist of a carrier signal Y 
(luminance signal) within the color bar signal, and a 
chroma or color signal (CbCr).
Contrast
The relative brightness of the light and dark areas of an 
image can be increased or decreased in order to make text 
and graphics stand out more clearly, or to make them 
appear softer.
Cool-down
This is the process by which the projector's lamp is 
cooled down after it has become hot through use. It is 
carried out automatically when the [Power] button on 
either the remote control or the projector's control panel 
has been pressed to turn off the projector. Do not turn off 
the main power switch while cool-down is in progress, 
otherwise the cool-down process will not work properly. 
If the cool-down period is not allowed to finish normally, 
the projector's lamp and internal components will remain 
at high temperatures, and this may shorten the useful life 
of the lamp or cause problems with the operation of the 
projector. The projector takes about 30 seconds to cool 
down. The actual time will vary depending on the 
external air temperature.
HDMI
An abbreviation for High Definition Multimedia 
Interface, and refers to a standard for digital transmission 
of high-definition images and multi-channel audio 
signals.
HDMI is a standard that is targeted towards household 
digital equipment and computers that allows digital 
signals to be transmitted in their original high quality 
without compression, and it also includes a digital signal 
encryption function.
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  , i = interlaced )
• Screen aspect  of 16:9
• Dolby Digital audio reception and playback (or output)
Interlace
A method of image scanning whereby the signal 
bandwidth used is approximately half that required for 
sequential scanning when images with the same still 
picture resolution are broadcast.
NTSC
An abbreviation for National Television Standards 
Committee, and a format for ground-based analogue 
colour television broadcasts. This format is used in Japan, 
North America and Central and South America.
PAL
An abbreviation for Phase Alternation by Line, and a 
format for ground-based analogue colour television 
broadcasts. This format is used in Western European 
countries except France, and also in Asian countries such 
as China and in Africa.
Progressive
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.
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
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 HDTV.
SECAM
An abbreviation for Sequential Couleur A Memoire, and 
a format for ground-based analogue colour television 
broadcasts. This format is used in France, Eastern Europe 
and the former Soviet Union, the Middle East and Africa.