Epson EMP-62, EMP-X3 manual Glossary

Glossary 68

The following is an explanation of some of the terms used in this guide which may be unfamiliar or which are not explained in the text of this guide itself. 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 Temp.	The temperature of an object that is emitting light. If the colour temperature is high, the colours take on a bluish tinge. If the
	colour temperature is lower, the colours take on a reddish tinge.
Component video	Video signals which have the video brightness signals and colour 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 (colour difference signals).
Composite video	Video signals which have the video brightness signals and colour 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 (colour) signal which are contained in the colour 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".
Dolby Digital	A sound format developed by Dolby Laboratories. Normal stereo is a 2-channel format which uses two speakers. Dolby
	Digital is a 6-channel (5.1-channel) system which adds to this a centre speaker two rear speakers and a sub-woofer.
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 = progressiveg, i = interlacedg)
	•Screen aspect ratiog of 16:9
	•Dolby Digitalg audio reception and playback (or output)
Interlaced	A method of image scanning whereby the image data is divided into fine horizontal lines which 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	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 colour 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).
SDTV	An abbreviation for Standard Definition Television. It refers to standard television systems which do not satisfy the conditions
	for High-Definition Television.