Glossary

Interlaced

A method of image scanning whereby the lines in a single image are divided into two sections

 

or "fields". The signal bandwidth used for interlaced scanning is approximately half that

 

required for progressive scanning when images with the same still picture resolution are

 

broadcast.

 

 

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.

 

 

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 images

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 High-Definition Television.

 

 

sRGB

An international standard for color intervals that was formulated so that colors which are

 

reproduced by video equipment can be handled easily by computer operating systems (OS)

 

and the Internet.

 

 

SVGA

A type of image signal with a resolution of 800 (horizontal) x 600 (vertical) dots which is

 

used by IBM PC/AT-compatible computers (DOS/V computers).

 

 

SXGA

A type of image signal with a resolution of 1280 (horizontal) x 1024 (vertical) dots which is

 

used by IBM PC/AT-compatible computers (DOS/V computers).

 

 

Synchronization

The signals output from computers have a specific frequency. If the projector frequency does

(Sync.)

not match this frequency, the resulting images will not be of a good quality. The process of

 

matching the phases of these signals (the relative position of the crests and troughs in the

 

signal) is called "synchronization". If the signals are not synchronized, problems such as

 

flickering, blurriness and horizontal interference can occur.

 

 

Tracking

The signals output from computers have a specific frequency. If the projector frequency does

 

not match this frequency, the resulting images will not be of a good quality. The process of

 

matching the frequency of these signals (the number of crests in the signal) is called

 

“tracking”. If tracking is not carried out correctly, wide vertical stripes will appear in the

 

projected images.

 

 

UXGA

A type of image signal with a resolution of 1600 (horizontal) x 1200 (vertical) dots which is

 

used by IBM PC/AT-compatible computers (DOS/V computers).

 

 

VGA

A type of image signal with a resolution of 640 (horizontal) x 480 (vertical) dots which is

 

used by IBM PC/AT-compatible computers (DOS/V computers).

 

 

XGA

A type of image signal with a resolution of 1,024 (horizontal) x 768 (vertical) dots which is

 

used by IBM PC/AT-compatible computers (DOS/V computers).

 

 

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