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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.

Colour temperature

The temperature of an object which is emitting light. If the 
colour temperature is high, the colors tend to take on a 
bluish tinge. If the colour temperature is lower, the colors 
tend to take on a reddish tinge.

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 disconnect the 
power cable 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 cool-down period lasts for about 5 minutes. 
The actual time will vary depending on the external air 
temperature.

Gain

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 brighter 
ranges separately for R, G and B components.

Gamma

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 intermediate 
ranges separately for R, G and B components.

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.

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.

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 .