Product guide
DICOM (Digital Imaging and Communications in Medicine)
provides the medical profession with the ability to simulate
21 different levels of grayscale in the rendering of X-rays,
CAT scans, MRIs and other medical imaging applications.
Digital Signage Advertising An ad-based digital
signage network displaying dynamic brand advertising
Digital Signage Display Refers to the LCD, Plasma,
TV or LED screen used in a dynamic digital signage
network.
Digital Signage Network A digital signage network is
a series of interconnected at panel screens or televisions
that are presented similar to traditional signage, but can
be controlled from a remote location to deliver dynamically
changing content.
Digital Signage Networks A grouping and/or network
of digital signage.
Digital Signage Software An end-to-end software
solution for digital signage networks. The software, much
like Scala, provides a content creation solution, a content
management solution managed from a central location and
playback functionality located near the display screens.
The software also provides for system maintenance, health
checking, advertising afdavit creation and management,
automatic scheduling, playlist creation and management,
meta tagging and user security.
Digital Signage Solution The complete end-to-end
digital signage solution available in one software platform.
Digital Signage An industry whereby plasma display
panels (PDPs), liquid crystal displays (LCDs), computer
monitors and normal televisions are used to replace and
enhance traditional signs. The advantages of digital signage
include the rapid ability to update content, and the ability
to deliver the RIGHT messages to the RIGHT audiences at
the RIGHT location. Digital signage is helping to merge the
industries of advertising networks and point of purchase
display merchandising.
Digital Zoom This function enables the zooming in and
out of images quickly whilst retaining picture quality.
D-ILA (Direct Image Light Amplication) is a technology
patented by Hughes-JVC designed to improve the light
output and contrast ratio of LCD screens.
Display Range The range of display sizes, such as
horizontal screen dimension of a at-panel, that can me
supported on any given mount. The display size is becom-
ing less important with the increasing size of the display
diagonal and the decrease in weight.
DisplayPort A digital display interface developed by the
VESA. The interface is primarily used to connect a video
source to a display device such as a computer monitor,
though it can also be used to transmit audio, USB, and
other forms of data. Display Port can be used to transmit
audio and video simultaneously. The DisplayPort signal is
not directly compatible with DVI or HDMI but passive adapt-
ers can be used to adjust the signal levels and convert the
connector style.
Distortion A usually undesirable variation from an in-
tended output caused by the characteristics of a particular
device.
Distribution Amplier An amplier used to maintain
a clean noise free signal to a projector or at panel device
over signicant distances. Even with good heavily shielded
cables, range of video and computer signals is limited to
a few dozen feet before noticeable degradation. In ceiling
mount situations, where the wiring may pass along side
or across electrical conduits, a distribution amp may be
needed with shorter distances. Many distribution amps can
also split the signal into 2 or more amplied signals for driv-
ing multiple projectors or at panels.
Dithering Method of displaying intermediate colors that
don’t exist in a limited palette by using a pattern of small
dots out of that palette.
DLP (Digital Light Processing) is a commercial name
for a display technology from Texas Instruments (TI). The
technology inside is often referred to as DMD (Digital Micro-
Mirrors). It consists of an array of mirrors where each mirror
represents a pixel element. For example, a high-denition
DLP projector or rear projector with 1920 x 1080 pixel
resolution would have over 2 million tiny mirrors. Each mirror
is attached to an electronically driven hinge that controls the
amount of colored light that is reected from the mirror into
the projection lens and onto a screen. Projection systems
using DLP technology use 1 to 3 DMD devices.
DMD (Digital Micromirror Device). Name of the actual
imaging chip used in a Texas Instruments DLP projection
systems.
DNS (Domain Name System). refers to the name resolu-
tion system that allows users to locate computers on a Unix
network or the Internet (TCP/IP network) by domain name.
The DNS server maintains a database of domain names
and their IP addresses.
Document Camera A document camera can be at-
tached to any projector; however, there are projectors that
integrate these features either as a camera on an arm that
is attached to the projector or a document scanner that is
built into the body of the projector.
Dolby Digital A lossy compression system to deliver
sound on DVDs, ATSC and DBS broadcasts in up to 5.1
channels. Also called AC-3. See AC-3.
Dolby EX Backwards compatible system to add a sixth
channel used for the middle rear playback to Dolby Digital
(AC-3) making it 6.1 or 7.1 sound. 7.1 sound uses an ad-
ditional center rear speaker playing back a duplicate track.
Needs a Dolby EX decoder. See AC-3.
Dolby Pro Logic II Updated version of Pro Logic. Of-
fers better performance with playing back non-encoded
sources over a surround sound system with full spatial cues
and delity.
Dolby Pro Logic An analog 4 channel surround sound
system with left, right, center channels and a mono rear
channel, typically duplicated across 2 speakers. Rear
channel is limited to 7KHz and system stores all channels in
a matrix recording on 2 discrete analog channels. Has dif-
culty playing back non-encoded material at full delity.
Dot Crawl Video artifact where little dots crawl along
the borders of differing colors, particularly noticeable on
graphics. Effect of composite encoding and easily removed
by using s-video or component cabling. Will not disappear
if the source was recorded using composite video and the
artifact has been recorded.
Dot Pitch The distance between side-by-side phosphor
color groups (RGB) on a direct view display that uses phos-
phors. The smaller the better.
Downward Tilt A downward inclination from the vertical
plane (i.e. the wall); a downward slant.
DPI (Dots Per Inch) refers to the number of pixels in a
single inch line.
DRM (Digital Rights Management) is the technology
which maintains the protection of digital content through
encryption.
Drop Ship For customers who do not have enough stor-
age or need to have product delivered directly to a job site,
select manufacturers will drop-ship orders according to
customer specications.
Dropout Missing information from a broadcast or
recorded media and typically show up as white specks
in an analog environment. Dropout is more pronounced
with interframe compression techniques such as MPEG
because the error displays until the next complete frame is
drawn, otherwise known as an I-frame. This can take up to
½ a second.
DTS Digital Theater Systems. An alternate method of en-
coding multi-track audio used on DVDs and other sources
like D-VHS. Offers less compression compared to Dolby’s
more common AC3 system and, arguably, better delity.
DTV (Digital Television). A system that uses digital signals
instead of analog including the ATSC standards, DBS and
digital cable.
Dual Lamp A Dual Lamp projector has two lamps where
one lamp either serves as an automatic backup to the other
lamp or is preprogrammed to switch at specic intervals.
The benet of this type of lamp system is it signicantly
reduces the probability of lamp failure during use.
Dual XD Engine Combines two of LG’s exclusive XD
Engines to help maximize picture quality for any kind of
video content. By combining XD Engine processors, panel
performance is optimized ensuring higher-quality, more
realistic images.
DVI (Digital Visual Interface) represents the interface
between projectors and computers through a digital con-
nection, resulting in a clearer image than that produced
through an analogue connection.
DVI (Digital Visual Interface). DVI is a standard that denes
the digital interface between digital devices such as projec-
tors, at-screens and personal computers. For devices
that support DVI, a digital-to-digital connection can be
made that eliminates the conversion to analog and thereby
delivers an unblemished image. It can also carry an analog
signal and comes as DVI-I (integrated - analog and digital),
DVI-D (digital only) and DVI-A (analog only). Dual link DVI
connections add additional resolution capabilities. Digital
cable lengths should not exceed 15 feet. Specications on
DVI are available at www.ddwg.org.
DVR (Digital Video Recorder). Also known as a PVR or
Personal Video Recorder. A hard disk based video recorder,
which usually offers long recording times and the capability
to pause incoming broadcasts. When the unit has access to
electronic programming guides, it can record shows on an
ongoing basis as well as do keyword and genre searches.
Dynamic Range The difference between the maximum
signal level and the noise oor in electronic equipment,
represented in dB. (See Decibel)
Dynamic Range The ratio between the highest and
lowest levels a device can perform. For a video device it is
a measure of contrast ratio. For an audio device it is usually
stated in dB.
E
Echo Cancellation The built-in process which
eliminates any acoustic echo in a video
conferencing environment.
Eco-Mode Technology A money-saving, highly ef-
cient feature that doubles lamp life and produces a quieter
operation.
Edge Blending When more than one projector is used
side by side to project wider content into a seamless wide
image, Edge Blending technology can be used. Edge
blending can be done in the projector or with an external
video processor. Edge blending works to remove the bright
visible band that occurs when two images overlap. Edge
blending will gradually fade out one of the images in the
banded zone while the adjacent image is gradually faded
up.
Edge Enhancement A technique used to increase
apparent resolution by increasing contrast around object
edges. Usually counterproductive with already high-resolu-
tion sources and can become a source of image distortion.
PRO AV GLOSSARY
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