Epson 1EMP-S1 manual Refresh Rate

Appendices > Glossary

Refresh Rate	The light-emitting element of a display maintains the
	same luminosity and colour for an extremely short
	time. For this reason, 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).
Resized display	This function is used to project computer images that
	have a resolution more than or less than the
	projector's panel resolution, so that they fill the
	whole of the projection area.
SDTV	An abbreviation for Standard Definition Television.
	It refers to standard television systems which do not
	satisfy the conditions for High-Definition Television.
Security	A device consisting of a projector case with a hole in
lock	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.
Squeeze	The method of compressing 16:9 Widescreen images
mode	and recording them on video software as 4:3 images.
	When projecting with Squeeze mode on, the images
	will return to their original 16:9 format.
sRGB	An international standard for colour intervals that
	was formulated so that colours which are reproduced
	by video equipment can be handled easily by
	computer operating systems (OS) and the Internet.

	EMP-S1 User’s Guide	63
SVGA	A type of video signal with a resolution of 800
	(horizontal) ⋅ 600 (vertical) dots which is used by
	IBM PC/AT-compatible computers.
S-Video	A type of video signal which has the video
	brightness and colour signal information separated,
	in order to provide better image quality. It refers to
	images which consist of two independent signals:
	Y(luminance signal), and C (colour signal).
Sync.	The signals output from computers have a specific
(Synchronisation)	frequency. Image quality will suffer if the projector
	frequency and the computer frequency do not match.
	The process of matching the phases of these signals
	(the relative position of the crests and troughs in the
	signal) is called "synchronisation". If the signals are
	not synchronised, problems such as flickering,
	blurriness and horizontal interference can occur.
Tracking	The signals output from computers have a specific
	frequency. Image quality will suffer if the projector
	frequency and the computer frequency do not match.
	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.
VGA	A type of video signal with a resolution of 640
	(horizontal) ⋅ 480 (vertical) dots which is used by
	IBM PC/AT-compatible computers.
XGA	A type of video signal with a resolution of 1,024
	(horizontal) ⋅ 768 (vertical) dots which is used by
	IBM PC/AT-compatible computers.