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Appendix
Glossary
Following is an explanation of some of the terms used in this guide that may be unfamiliar or that were not
explained in the text of this guide. Further information can be obtained by referring to other commercially-
available publications.
Aspect ratio
The ratio between an image's length and its height. HDTV images have an aspect ratio of
16:9 and appear elongated. The aspect ratio for standard images is 4:3.
Color temperature
The temperature of an object which is emitting light. If the color temperature is high, the
colors tend to take on a bluish tinge. If the color temperature is lower, the colors tend to
take on a reddish tinge.
Component video
Video signals that 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 that 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).
The carrier signal Y (luminance signal) and chroma (color) signal that are contained in
the color bar are overlapped to form a single signal.
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. Adjusting this particular property of an image is called “contrast
adjustment.”
Cool-down
The cooling process for the projector's lamp unit continues even after the [Power] button
on the projector's control panel or the remote control has been pressed to turn off the
projector. After the lamp turns off, the cooling fan continues operating, but all button
operations are disabled. The period of time during which this happens is called the “cool-
down period.” The cool-down period lasts for about 25 seconds. The actual time varies
depending on the external air temperature.
Dolby Digital
A sound format developed by Dolby Laboratories. Normal stereo is a 2-channel format
that uses two speakers. Dolby Digital is a 6-channel (5.1-channel) system that adds to
this a center speaker, two rear speakers and a sub-woofer.
HDTV
An abbreviation for High-Definition Television. It refers to high-definition systems that
satisfy the following conditions.
Vertical resolution of 720p or 1080i or greater (p = progressive scanning
, i = interlaced
scanning )
Screen aspect ratio
of 16:9
Dolby Digital
audio reception and playback (or output)
Interlaced scanning
A method of image scanning whereby the image data is divided into fine horizontal lines
that are displayed in sequence starting from left to right and then from the top to the
bottom of the screen. The even-numbered lines and odd-numbered lines are displayed
alternately.
Progressive
scanning
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).
Resize display
This function is used to project computer images that have a resolution of more than or
less than the projector's panel resolution, so that they fill the whole projection area.
SDTV
An abbreviation for Standard Definition Television. It refers to standard television
systems that do not satisfy the conditions of High Definition Television.
Security lock
A device consisting of a projector case with a hole in it that a commercially-available
theft-prevention cable can be passed through in order to secure the device to a table or
pillar. This projector is compatible with the Microsaver Security System manufactured
by Kensington.
sRGB
An international standard for color intervals that was formulated so that colors that are
reproduced by video equipment can be handled easily by computer operating systems
(OS) and the Internet.
