Epson EMP-822H User Manual

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Glossary
This section briefly explains terms that are used with the projector and difficult terms that are not explained in the text of this guide. For details, 
refer 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. 
Component Video
A video signal which has the luminance component and color component separated to provide better image quality. 
Refers to images that consist of three independent signals: Y (luminance signal), 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 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". 
DHCP
An abbreviation of Dynamic Host Configuration Protocol, this protocol automatically assigns an IP address
g
 to equipment connected to 
a network.
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 which adds to this a center speaker, two rear speakers, and a sub-woofer. 
Gateway address
This is a server (router) for communicating across a network (subnet) divided according to subnet masks
g
.
HDTV
An abbreviation for High-Definition Television that refers to high-definition systems which satisfy the following conditions. 
• Vertical resolution of 720p or 1080i or greater (p = progressive
g
, i = interlace
g
)
• Screen aspect ratio
g
 of 16:9 
• Dolby Digital
g
 audio reception and playback (or output) 
Interlace
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 top to bottom. The even-numbered lines and odd-numbered lines are displayed alternately. 
IP address
A number to identify a computer connected to a network.
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 color for an extremely short time. Because of this, the image 
must be scanned many times per second 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 that refers to standard television systems which do not satisfy the conditions for 
HDTV
g
 High-Definition Television. 
SNMP
An abbreviation for Simple Network Management Protocol, which is the protocol for monitoring and controlling devices such as routers 
and computers connected to a TCP/IP network.
SNMP Trap IP address
This is the IP address
g
 for the destination computer used for error notification in SNMP