| ANSI
lumens |
Brightness is measured
in ANSI (American National Standards Institute)
lumens: the brighter the projector, the higher the
ANSI lumen rating. |
| Aspect
Ratio |
Aspect ratio is the
ratio of the width of an image to its height. The
most popular aspect ratios are 4:3 (4 by 3) and
16:9 (widescreen). |
| Component
Video |
Component Video is
a method of delivering quality video (RGB) in a
format that contains all the components of the original
image. These components are referred to as luma
and chroma and are defined as Y'Pb'Pr' for analogue
component and Y'Cb'Cr' for digital component. |
| Composite
Video Signal |
The combined picture
signal, including vertical and horizontal blanking
and synchronizing signals. |
| Contrast
Ratio |
The ratio between
white and black. The larger the contrast ratio the
greater the ability of a projector to show subtle
colour details and tolerate room light. |
| Digital
Light Processing (DLP) |
A commercial term
from Texas Instruments (TI) otherwise referred to
as DMD. It works by the alignment of thousands of
tiny mirrors, lined up in 800 rows of 600 mirrors
each. Each micro mirror is hinged and motorised
with electrostatic energy allowing them to be tilted
at incredible speeds, modulating the light from
a lamp so it can be sent through a lens, on to the
screen. |
| DVI |
Digital Visual Interface
between digital devices such as projectors, flatscreens,
video conferencing systems and PCs. |
| DVI-I |
A connector that
has the capability of carrying either digital or
analog video signals. This connector can be converted
to the common 15-pin VGA connector with a DVI-I
to VGA adapter making the input compatible with
standard VGA cables. |
| DVI-D |
A connector that
has the capability of carrying digital video signals.
This connector is very similar in appearance to
the DVI-I connector but lacks the ability to carry
analog video signals. |
| EcoMode |
An option that increases
lamp life by lowering lamp power. When this feature
is engaged, the projector's brightness level will
be reduced by approximately 20%. |
| Focal
Length |
The distance from
the surface of a lens to its focal point. |
| Keystone
Correction |
This takes a trapezium-shaped
image caused by mounting a projector at an angle,
and makes it into rectangular one for alignment
with screen. |
| LCD |
Liquid Crystal Display
technology. It is used in flats screens and projectors
to present a digital image for viewing. |
| Native
Resolution |
Native Resolution
refers to the number of physical pixels in a display
device. For example, an SVGA projector has 800 physical
pixels of resolution horizontally and 600 pixels
vertically or 480,000 total pixels. This is the
native resolution of the projector. Projectors are
capable of projecting greater or smaller resolution
images into the same physical resolution through
scaling. |
| NTSC |
The United States
broadcast standard for video and broadcasting. Lower
resolution than PAL systems used in most of the
world. |
| PC-Less
Presentation |
Projector accepts
a standard PCMCIA memory card and can play back
a saved PowerPoint® presentation without a computer. |
| Progressive
Scan |
A type of display
in which all the horizontal lines of an image are
displayed at one time in a single frame, unlike
an Interlaced Scan in which a frame consists of
two separate fields with the first field consisting
of odd horizontal lines and the second field even
horizontal lines. |
| Rear
Screen Projection |
Using an opaque screen,
the projector is placed behind the screen, invisible
to the audience. It projects onto the screen and
the audience sees it on the other side eliminating
shadows from the presenter. Ideally a projector
with a short throw lens is used to minimise wasted
space behind the screen. |
| Resolution |
The amount of pixels
that make up an image - e.g. 640 x 480 means 640
pixel groups across the image by 480 pixel groups
down. The larger the number of pixels the higher
the resolution and the sharper and more detailed
the image is. Common resolutions are VGA, SVGA,
XGA, SXGA, UXGA these represent increasing levels
of resolution. The 'W' prefix (eg WXGA) refers to
the resolution appropriate to displaying in wide-screen
aspect ratio. |
| RGB |
Red, Green, Blue;
the normal type of monitor used with computers.
Example of usage: RGB input or output often referred
to as Computer input or output. |
| S-Video |
A video transmission
standard that uses a 4 pin mini-DIN connector to
send video information on two signal wires called
luminance (brightness,Y) and chrominance (colour,
C). S-Video is sometimes referred to as Y/C. Unlike
a composite signal found on a phono/RCA connection
where the Y and C information is combined into one
signal, S-Video has its luminance and chrominance
separated meaning that a comb filter (which can
reduce the sharpness of the image) is not needed
inside the projector. |
| SVGA |
800 horizontal pixels
by 600 vertical pixels giving a total of 480,000
individual pixels on screen. |
| SXGA |
1,280 horizontal
pixels by 1,024 vertical pixels giving a total display
resolution of 1,310,720 pixels. |
| Throw
Ratio |
A ratio between projection
distance and width of image. For example, a throw
ratio of 1.8:1 means that the projector must be
18' away from the screen to result in a 10' wide
image. |
| UXGA |
1,600 horizontal
pixels by 1,200 vertical pixels giving a total display
resolution of 1,920,000 pixels. |
| VGA |
640 horizontal pixels
by 480 vertical pixels giving a total display resolution
of 307,200 pixels. |
| WiFi |
Wireless Fidelity
and is based on the IEEE 802.11 specifications for
wireless local area networks (WLAN). There are four
specifications in the family: 802.11, 802.11a, 802.11b,
and 802.11g. All four use the Ethernet protocol. |
| Zoom
Range |
The ratio between
the smallest and largest image size by adjusting
only the projector's zoom lens. |
