Dell 1100MP, Руководство пользователя

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Glossary 55
Glossary
ANSI Lumens— A standard for measuring light output, used for comparing
projectors.
Aspect Ratio— The most popular aspect ratio is 4:3 (4 by 3). Early television and
computer video formats are in a 4:3 aspect ratio, which means that the width of
the image is 4/3 times the height.
Backlit (Backlight)— Refers to a remote control, or a projector control panel, that
has buttons and controls that are illuminated.
Bandwidth— The number of cycles per second (Hertz) expressing the difference
between the lower and upper limiting frequencies of a frequency band; also, the
width of a band of frequencies.
Brightness— The amount of light emitting from a display or projection display or
projection device. The brightness of projector is measured by ANSI lumens.
Color Temperature— A method of measuring the whiteness of a light source.
Metal halide lamps have a higher temperature compared to halogen or
incandescent lights.
Component Video— A method of delivering quality video in a format that
contains all the components of the original image. These components are referred
to as luma and chroma and are defined as Y'Pb'Pr' for analog component and
Y'Cb'Cr' for digital component. Component video is available on DVD players and
projectors.
Composite Video— The combined picture signal, including vertical and
horizontal blanking and synchronizing signals.
Compression— A function that deletes resolution lines from the image to fit in
the display area.
Compressed SVGA— To project an 800x600 image to a VGA projector, the
original 800x600 signal must be compressed down. The data displays all the
information with only two thirds of the pixels (307,000 vs 480,000). The resulting
image is SVGA page ize but sacrifices some of the image quality. If you are using
an SVGA computers, connecting VGA to a VGA projector provide better results.
Compressed SXGA— Found on XGA projectors, compressed SXGA handling
allows these projectors to handle up to 1280x1024 SXGA resolution.
Compressed XGA— Found on SVGA projectors, compressed XGA handling allows
these projectors to handle 1024x768 XGA resolution.