65
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 addressg 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 masksg.
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 = progressiveg, i = interlaceg)
• Screen aspect ratiog of 16:9
• Dolby Digitalg 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
HDTVg 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 addressg for the destination computer used for error notification in SNMP