Glossary of Projector Terms
4K
4K projector resolution is different to 1080, 1080 refers to the height of 1920x1080, 4K refers to the width of the image resolution.
There are three 4K standards:
- 4K2K - has a resolution of 4096x2400
- 4K DCi - has a resolution of 4096x2160 used in commercial cinema projectors.
- 4K UHD - has a resolution of 3860x1080 and is mainly used in home theater and data projectors. You may notice that UHD is double the resolution of Full HD (1920x1080). Some projectors use FHD panals with pixel shift, effectivly
doubling the resolution to achieve 4K-UHD
5K
5K (5120x3200 pixels) refers to resolution. Where as 1080p refers to the height of 1920x1080, 5K refers to the width of the image resolution.
8K
An 8K projector has a resolution of 8192x4320 pixels. Where as 1080p refers to the height of 1920x1080, 8K refers to the width of the image resolution.
Ambient Light
Any light in the viewing room created by a source other than the projector or screen.
Aliasing
Jagged edges along the outer edge of objects or text. Anti-aliasing refers to software adjustments that correct this effect.
This effect is created by inadequate sampling techniques in computer-produced images.
Anamorphic Lens
An Anamorphic lens is a lens that optically distorts the image. First developed in the film industry to use standard 35mm film
to record images in widescreen format. The camera was fitted with a widescreen format lens that optically compressed the image so that it would fit into a 35mm film frame. Then when the film
was played through a projection system, the projector was fitted with another lens that reversed the distortion. In that way the compressed image that was recorded on the 35mm film was
projected onto the screen in natural, uncompressed widescreen format. Now on projectors anamorphic lenses are used to convert 4:3 native projectors to widescreen.
There are two types of anamorphic lenses on the market. One compresses the image vertically, and the other expands the image horizontally. A potential problem to be aware of when
considering the use of an anamorphic lens is this: What do you do when you want to see regular 4:3 material? When you put a lens that optically distorts what is being projected in front of your
projector, it distorts everything, whether it is pre-compressed 16:9 or not. So when you try to play native 4:3 material through it, you get an image that is distorted horizontally--people are shorter and
fatter than normal.
Anamorphicly Squeezed
This process, which is used on few laserdiscs, a few DVDs and even fewer TV broadcasts, is used to achieve a widescreen image,
where the image is considerably wider than standard NTSC fare, once it is 'unsqueezed'. The wider image is squeezed into the skinnier aspect ratio, which is usually the NTSC standard of 4:3/1.33:1.
Unsqueezing can be done with a 'stretching circuits' in the TV. The end result (if left unsqueezed) is a picture with really skinny objects. Another option which has less detail, but is more widely
used is letterboxing the picture.
ANSI Lumens
ANSI stands for American National Standards Institute. It is a standard for measuring light output. Different lamps play a role on light output.
Halogen lamps appear dimmer than another metal-halide, even if the two units have the same ANSI lumen rating. Type of LCD technology (active matrix TFT, Poly-Si, passive), type of overall technology
(LCD vs. DLP vs. CRT), contrast ratios, among other factors can also affect the end result.
Aspect Ratio
The ratio of height to width of a frame or screen. In a 4:3 aspect ratio, the width of the image is 4/3 times the height.
Most current TV and computer video formats are in a 4:3 aspect ratio. A 15 inch monitor is 12 inches wide by 9 inches high (9*4/3 = 12). A resolution of 640x480 is a 4:3 format (480*4/3 = 640).
SXGA is a 5:4 aspect ratio is (1280x1024), HDTV is 16:9 for that movie theatre feel, and 35mm slides are 3:2.
Auto Position
A one-touch function to perfectly fit the signal format in the projector to the signal format actually fed from the computer.
By activating this function, the picture quality projected on the screen becomes perfectly synchronized
Backlit
A remote control, projector control panel, or other object illuminated from behind. This can be helpful when working in darkened rooms.
Bandwidth
The frequency range of a particular transmission method. In video systems, this value is expressed in MHz, and the better the signal,
the greater the bandwidth required.
Bit Mapped Graphics
The type of graphic that is defined and addressed on a bit-by-bit basis which makes all points on the screen display directly accessible.
Black Board Mode
When projecting images on a classroom blackboard without a screen, image colours will be tinged with green. Some projectors can compensate for this.
Colours and tones of projected images and characters will be similar to ones that are projected on a white screen if the "Blackboard Mode" is selected .
Black Level
Video black level is the defined as the level of brightness at the darkest (black) part of a visual image or the level of brightness at
which no light is emitted from a screen, resulting in pure black.
Blooming
This happens when bright parts of images seem to cast their brightness onto surrounding images. Solution: Try turning down the Contrast,
or if possible the colour gain controls.
BNC
Used with coaxial cables, this connector receives all R, G, B, H-Sync and V-Sync information, and composite video.
BrilliantColor
A Texas Instruments technology used in DLP Projectors to increase colour accuracy. The technology features multi-color processing and
allows users to adjust each colour independantly. BrilliantColor also increases color brightness by up to 50%.
Build Slide
"Build series" slides show audiences where a topic is heading a line at a time. Each new line added appears in a bright colour while
previous the line drops back to a darker colour.
Button
A graphic element inside an interface that represents an embedded action or function.
Chrominance
A colour term defining the hue and saturation of a colour. Does not refer to brightness
Clip-Art
Graphics that have been previously published which can be imported into a presentation simply by copying and pasting.
Colour Resolution
The total number of colours available, expressed in bits per pixel.
Colour Temperature
A measurement of white colour chromaticity as a result of a balanced mixture of red, green and blue. Higher colour temperature gives bluish
white (cool white) and lower colour temperature gives reddish white (warm white)
Component Video Signal
Most advanced video signal format. Separated to luminance signal and two color component signals. Two different formats available
(High-end DVD players provide Y.CB.CR. component video signal. HDTV decoders provide Y.PB.PR. component video signal.)
Composite Signal
A traditional video signal format. Luminance signal and chroma (color) signal are consolidated into one video signal in this format
while they are split in S-Video (or S-VHS) signal format. Usually interfaced through RCA plug and jack. (Also see "RCA Connection".)
Compatible
When different hardware or software can be used together without a major over-haul.
Contrast
A user adjustment to increase or decrease the contrast between the bright area and dark area of a picture.
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 extraneous room light. There are two methods used by the projection industry: 1) Full On/Off contrast measures the ratio of the light output of an all white image (full on) and
the light output of an all black (full off) image. 2) ANSI contrast is measured with a pattern of 16 alternating black and white rectangles. The average light output from the white rectangles is divided
by the average light output of the black rectangles to determine the ANSI contrast ratio. When comparing the contrast ratio of projectors make sure you are comparing the same type of contrast.
Full On/Off contrast will always be a larger number than ANSI contrast for the same projector.
D6 LCD
Epson D6 series high-temperature polysilicon TFT liquid crystal panels are equipped with hybrid driving technology that further enhances the performance of its 3LCD-type front-projectors
and large screen LCD projection TV.
The D6 series panel, which incorporates the “Crystal Clear Fine” inorganic alignment layer HTPS technology, is a 0.7-inch model designed for true-HD-ready (1080p) TV systems and front-projectors
for home.
The D6 series employs a hybrid technology that uses internal and external drivers for driving the LCD. Preceding products called for horizontal driver IC to be provided inside the panel.
Externally mounted horizontal driver ICs, as used in the D6 series technology, have superior driving capabilities.
In addition to the D6 series panel’s own features, C2 Fine’s capabilities are also effectively incorporated to achieve high contrast, produce smooth images, and reproduce jet black,
resulting in high-definition images. The D6 series panel, which incorporates these technologies and provides true HD (1080p), will allow users to enjoy with simplicity and ease high-definition
image quality on projection systems employing the 3 LCD design and front home projectors
D7 LCD
The new Epson D7 panels also feature the following points:
- A 20% improvement in aperture ratio compared to the previous model of the same size.
- Improved color reproduction by using a 12-bit LCD driver.
- Improved noise immunity by using a Mini-LVDS interface.
*Hybrid driving technology: Technology for driving LCD panels using both internal and external drivers.
Benefits for manufacturers of projection products offers enhanced luminance with the same lamp. Enables use of a lower-watt lamp to achieve the same luminance (reduced power consumption).
Epson have both reduced the panel size and increased the proportion of panel area allowing light through. This makes it possible for manufacturers to achieve higher luminance with the same
projector lamp or reduce the lamp wattage for the same result. Another improvement built-in to the D7 is the higher rate 12-bit LCD driver. This allows more colors and shades of gradation to be
represented. While the D6’s 10-bit driver could control 1.1 billion colors, the new 12-bit capability boosts performance by 64 times to 68.7 billion colors. Gradation levels jump from a possible
1,024 to 4,096. These performance boosts make it possible for Epson to support the new xvYCC (called x.v.Color) color standard.
D9 LCD
Developed and manufactured by Epson using the latest processing technologies, the HTPS panels employ 'Bright 3D Drive' - a new technology
that brightens 3D images by doubling the image refresh rate from 240 Hz to 480 Hz. The faster refresh rate results in 3D images that are at least 1.5 times brighter*2 than those created on panels
refreshed at 240 Hz. Epson applies this technology in a new range of 3D HTPS panels currently in volume production.
Nobuyuki Shimotome, Chief Operating Officer, TFT Operations Division, Epson, said, "Thanks to our new HTPS panels users will enjoy bright 3D images. In addition, projector manufacturers looking for
the quality and technical advantages that Epson provides, will also benefit from our new panels.
"For more than two decades Epson has maintained its position as the world's No. 1 supplier*3 of HTPS panels, the core devices at the heart of 3LCD projectors. While the expansion of the 3LCD
projector market has been driven primarily by business demand, today we see an increasing appetite for home cinema projectors capable of delivering stunning, bright 2D and 3D images. With our
new technology, we are confident that we will be able to meet that demand."
As the leader in the development and manufacture of HTPS panels, Epson will continue to meet customer demand with a range of HTPS panels and end products that employ cutting-edge liquid crystal
technology, high-aperture designs and other original features.
DDR
In computing, a computer bus operating with double data rate transfers data on both the rising and falling edges of the clock signal.
This is also known as double pumped, dual-pumped, and double transition.
Diagonal Screen
One corner of a screen to the opposite corner. A 9FT high, 12FT wide, screen has a diagonal of 15FT. If the screen is 12x12, it
would still rate 15FT diagonal since that would be the diagonal usable.
Desktop Videoconferencing
Videoconferencing via personal computer.
Digital Interface
The new generation interface between computer output and projector (or monitor) input. Instead of traditional interface with an
analogue signal, a digital signal is used through DVI cable so that picture quality is not distorted and synchronization is more stabilized. Only applicable when digital signal output from computer
and digital signal input terminal on projector (or monitor) are provided.
Digital Light Processing (DLP)
Developed by Texas Instruments, DLP is a light processing system that utilized hundreds of thousands of tiny spinning mirrors
to reflect images. Many feel it is the most accurate reproduction of colour and images available today.
DTS
Digital Theatre Systems, An 8-channel sound format used in commercial movie theatres. Only 6 are used, and the sound is run off CD's.
The supposed follow-up for home theatre is DTS Coherent Acoustics.
DVD
Digital Versatile Disc, Previously known as Digital Video Disc, this represents the latest in home theatre. It is a purely digital
format use MPEG-1 and/or MPEG-2 compression. This may result in artefacts such as pixilation. The format is also has the ability to have multiple aspect ratios, several different versions of a
movie with several different captions as well as Dolby Digital sound. Each disc consists of two layers so that when the end of one layer is reached, the laser beam focuses down to the next layer
for a seamless layer change
Dithering
The mirrors on the digital micro mirror device have two positions on or off. Unlike LCD which can project shades by varying the
light transmission of the LCD panels DLP can not be partially on. In the on position the mirror reflects light. In the off position no light is reflected - black is projected. DLP systems uses
Dithering to project Grey. The process involves increasing the DLP mirrors switching speed. So that only a partial amount of light is projected compared to the normal on time. As with the
sequential colour projection, your eye is not supposed to perceive this rapid switching and only see the desired grey. The side effect of dithering is that it can produce some visible instability
in solid colours especially in darker areas of the image. This instability is commonly referred to as dithering artefacts.
Dolby AC-3
The old name for the most popular 5.1-channel home theatre sound system. Is now called Dolby Digital. Consists of front
left/right speakers, a centre speaker, left/right surrounds, and a Low Frequency Effects (LFE) channel, usually used with a subwoofer.
Dolby Digital Surround EX
1 - Dolby's latest surround format. It is essentially Dolby Digital with an added centre rear channel. Some would call this setup a
6.1 channel setup, but that would be misleading. The rear centre channel is mixed into the other rear channels, and is extracted upon playback. This is very similar in fashion to Dolby Pro-Logic
and matrixed surround. It premiered with Star Wars Episode I: The Phantom Menace. DVD players are just starting to support this format
Dolby Pro-Logic
Most popular surround format. Almost any receiver nowadays has it. Uses matrixed surround in order to encode four channels of
sound: left/right front channels, a centre channel, and one surround channel. It is quite a common occurrence to see two speakers used for the one surround channel however, as well as a subwoofer
to supplement the speakers.
Dolby Surround
The encoding process used to make material compatible with Dolby Pro-Logic.
2 - Another surround format that came out before Dolby Prologic. It consists of only three channels: left/right front channels, and one surround channel
Dot Crawl
Dot crawl is caused by a poorly designed comb filter or notch filter in the TV set. It is noticed at the boundary of two
colours and looks like a zipper with the two colours alternating. Best observed with a colour bar test pattern on the screen. It gives the illusion of motion like the sequential illumination
of lights on a marquee.
Dot Pitch
The distance between the dots on a CRT display. The closer together the dots are create a higher resolution of a displayed image.
DVI
DVI or Digital Visual Interface is a signal cable connected between computer output and projector (or monitor) input for digital signal.
EDTV
Enhanced Definition television- EDTV signal is progressive scan and has 525 lines, dos not require deinterlacing. Not as good as
HDTV but an improvement over standard TV signal.
EGA
Enhanced Graphics Array, EGA is an image which displays 640 pixels by 350 lines with 16 colours from a palette of 64 colours.
Front Room Projector or Position
A unit that sits close to the screen, its short throw lens projects an image size that is about the same as the distance to
the screen. 6FT diagonal. screen = 6FT distance. Generally the unit might be as close as 3/4 the screen size or as far as 1.2 times image size.
Flat Screen
A LCD, Plasma tv screen flat compared to a CRT tube TV.
Focal Length
Focal length is the distance between the lens and its focal point. A smaller focal length indicates a wider-angle lens.
Gain
A measurement usually made perpendicular to screen center of the luminance transmitted by the screen, divided by the
luminance radiating from the projector.
Genlock
Synchronizing signals between two video sources, which is necessary when overlaying computer graphics on an image
from VCR, camera, or videodisc player.
Ghosting
A shadow or weak secondary image as seen on a monitor or display which is created by multiple path broadcast transmission errors.
Grain
This shows up as speckles that do not belong in the picture. This is most noticeable in dark scenes. This can be cause
by several things. It can be caused by the quality of the material you are watching, or it can be caused by incorrect settings on a TV. Solution: If you know for sure that it is not
the source material, the problem might be that the SHARPNESS is set too high.
HDCP
HDCP (High-Bandwidth Digital Content Protection)
HDMI
HDMI or "High Definition Multimedia Interface" connector includes high quality digital sound capability as well as control signals. The digital signals carried by these cables are different than current analog signals and cause unique problems when transmitting the signal. HDMI is designed to perform better over longer lengths, but actual performance constraints are similar to DVI.
High Gain Screen
A screen that uses one of more methods to collect light and reflect it back to the viewing audience, which will increase the brightness of the image over a white-wall or semi-matte screen.
H-Sync
Horizontal synchronization. A marker, which indicates to a computer or video signal that it, is the beginning of a line.
HDTV
High Definition Television. High definition, wide-screen television broadcasting with digital audio. There are two types, 1080i- which has 1080 lines and is interlaced and 720p-which is 720 lines and progressive. 1080i gives better picture detail and 720p gives a better image for movement.
Horizontal Frequency
kHz, the total number of horizontal lines scanned per second in a displayed image.
Horizontal Resolution
The total number of vertical lines individually perceived across the horizontal rows of a monitor.
Hz
Hertz. A measure of frequency in cycles per second. Used to express the frequency of an electrical signal or event.
Image AI
Inferior alternative to Dynamic Iris that increases and decreases lamp brightness to boost image contrast. Slower response time than Dynamic Iris which may be noticeable in fast action scenes.
Invert Image
Many projectors that are ceiling mounted are mounted upside down. Invert image corrects the image digitally so your projected image is not also upside down.
Interlacing
Technique used to reduce flicker caused when the first created video field fades while the next is being written.
IRIS® (Intelligent Room Illumination Sensor)
Automatically detects light volume emitted in a room and color density, then automatically adjusts the mid-range color tones required for optimum color reproduction under any lighting conditions.
Jaggies
jagged diagonals especially common on text on lower resolution projectors
JPEG
Joint Photographic Experts Group. An international group, which is working, on a proposed universal standard for the digital compression and decompression of still images used in computer systems. The JPEG idea reduces image size as much as 65:1 and still maintains image integrity by getting rid of subtle colour differences the human eye can not see.
Keystone Correction
A projectors ability to correct the effects of "pointing up" or "pointing down" at a screen enabling the projector user’s audience to view a rectangular image rather than one with a wider top or bottom.
Key stoning
The distortion (usually a wide-top narrow-bottom effect) of a projected image caused by a projector "pointing up" or "pointing down" at its screen. Named after its similarity in shape to the keystone used in constructing an arch.
LCD
liquid crystal display. This technology comes in many forms, sizes, and resolutions. Its primary purpose is to present a digital image for viewing. They are used in many notebook computer displays and also used as technology inside a projector to project high-resolution digital images.
Lamp
The light source of the projector. Typically, a high-pressure mercury lamp.
Laser Pointer
A hand held device that emits a thin laser beam that focuses a bright dot (usually red) on projected images or just about anywhere. Used by presenters to direct the viewer's eye to a particular point of interest.
Lenticular
A screen surface that has an embossed geometric shaped pattern that affects view/angle performance and reflection of ambient light.
Letterbox
This process, which is used on many laserdiscs and some TV broadcasts, is used to achieve a widescreen image, where the image is considerably wider than standard NTSC fare. The end result is a wider picture with black bands on the top and bottom of the screen, which reduces the overall resolution of the image. Another option with greater detail, but is less widely used is anamorphically squeezing the picture.
Long Throw Lens:
A lens designed for projection from the back of a room. Long throw lenses would be used a projection booth in the back of a theatre, or from the back of a large classroom. A long throw lens would have to be 50 to 100 FT back to project a 10FT diagonal image.
Lux
The International System unit of illumination, equal to one lumen per square meter. It is equal to the illumination of a surface one meter away from a single candle
MH
Metal Halide Lamp - A lamp used in portable projectors. These lamps output a very "hot" temperature light, similar to lamps used in streetlights. Metal Halide whites are super white (with a hint of blue) and make Halogen lamp white very yellowish by comparison.
MHL
Mobile High-Definition Link (MHL) is an industry standard for a mobile audio/video interface that allows consumers to connect smart-phones, tablets, and other portable consumer electronics (CE) devices to high-definition projectors. It can be used for audio and video transfer or to charge devices.
Mini Plug, Mini Jack
A typical audio connection for various audio equipment. Two types (stereo, mono) are available. On Mitsubishi projectors, it is used for not only audio, but also for a wired remote control.
MLA
Micro Lens Array (MLA)is a way of optimizing the light output of a projector. The lens array looks like a sheet of bubble wrap, lots of small lenses that focus the light from the projector lamp. This reduces light lost through the lens system.
Multimedia Presentations
The integration of text, art, graphics, photography, animation, audio, and video into presentations.
Multiplexing
The condensing of many signals into a few or one signal that still represents all of them. An LCD panel performs the de-multiplex function. It takes video signals that contain whole frames of video data and displays them as individual signals on each pixel.
NTSC
The standard by which TV is broadcast in the US. It has a theoretical maximum resolution of 525 lines. Also has an aspect ratio of 4:3 or 1.33:1.
Natural Colour matrix
A unique colour processing technology exclusive to Mitsubishi. Natural Colour Matrix makes it possible to independently adjust the hue of red, green, blue, cyan, magenta, and yellow without interfering with each other. New Natural Colour Matrix features colour saturation (richer colour or pale colour) adjustment in addition to the independent hue adjustment feature. Natural Colour Matrix and New Natural Colour Matrix are an exclusive feature on Mitsubishi-made projectors.
Network
Allows two or more devices to exchange information quickly and easily.
Offset
With many projectors, the lens is designed to project the image at a slight elevation. This allows you to project onto a vertical surface without having to tilt the projector backwards and use Keystone Correction. If you draw a straight horizontal line from your projector's lens to your wall, the distance between that point and the lowermost point of your image is your offset distance. As the throw distance increases the offset height also increases, for this reason it is quoted as a percentage of the image height. Please be sure to take this into consideration when positioning your screen.
Output
Material that a computer generates from its memory for display on a monitor or for transfer to other media, such as paper or magnetic storage such as zip or floppy disks or a CD-ROM.
Overlay
The capability to superimpose computer-generated graphics and/or text on motion or still video.
Overhead Projector (OHP)
An OHP is designed to project images from transparencies onto a screen.
PCGC
Acronym for Personal Computer Graphic Control. In projectors, typically an on-screen display in the PC to command the projector or to communicate with the projector.
PCV
Acronym for PC Viewer. A software that makes it possible to save picture data from PC to PC card and project the picture from the PC card by the projector without a PC.
PAL
Phase Alternation by Line. The standard colour system used throughout Western Europe, except in France. It has a theoretical maximum resolution of 625 lines. Also has an aspect ratio of 4:3/1.33:1.
Pan and Scan
A technique used in which the right and/or left edges of widescreen material is chopped off in order to fit the picture into a narrower aspect ratio, for example the NTSC standard of 4:3 or 1.33:1. People who do this select the best part of the image to scan, and then if the whole image needs to be seen, scans across the rest of the frame.
Picture-in-Picture (P-in-P)
This features allows the user to show two images from different sources simultaneously.
Pixel
Short for picture element. The smallest element in a displayed image. A colour pixel is a combination of red, green and blue sub pixels. Total pixels are usually expressed in horizontal x vertical dimensions (e.g. 640 x 480).
Pixilation
This problem shows up on LCD projectors. Pixilation occurs when the number of pixels that an LCD projector shows is too little for the size of the screen. As a result the picture shows up as a bunch of boxes. Solution: There are two main solutions to this problem. The first and cheaper solution is to slightly defocus the picture slightly. This will not cost you anything. The other alter native is to buy a pixilation filter. This device struts its stuff on the end of the lens and gets rid of the pixels. The problem with this solution is that it softens and blurs the picture to the point where you may not be able to read credits. It also decreases the brightness of the picture, which is critical to an LCD projector setup
Poly-Si (silicon) LCD
A popular LCD technology for the top of the line LCD projectors, which results in increased colour saturation, with contrast ratios above 200:1.
Power Zoom
A zoom lens with the zoom in and out controlled by a motor, usually adjusted from the control panel or a remote control. This is as compared to Digital zoom, which does this same function Digitally.
Presentation Ergonomics
The study and science of optimizing relationships between a presenter and the presentation environment.
Projection Axis
Direction of the "imaginary" line that extends from the centre of the projection lens through the centre of the screen
Projection Distance
The distance between projector lens and projection surface. The image projected becomes larger the further the projector is from the projection surface. There are two projection distance figures: one for maximum width (wide-angle) and one for maxium distance (telescopic). The projector should be adjusted to project at the point between these two figures when using a projection surface (e.g., screen) with a fixed size. The projection distance for projection surfaces of various sizes can be calculated easily if the projector's "Throw Ratio" is known.
(See "Throw Ratio" for details.)
Projection resolution
Resolution of LCD panel (or DMD™ chip) of the projector
If a computer signal at XGA resolution is fed into a SVGA projector, the image projected will be seen at SVGA resolution. Usually, the (native) input signal from a computer is automatically converted to the projector's own resolution (In this case, native XGA is converte to SVGA). Re-scaling technology is applied for the conversion process.
QXGA
QXGA resolution is 2048 x 1536 pixels
Rainbow Effect
This visual artifact is best described as brief flashes of perceived red/blue/green "shadows" observed most often when the projected content features bright/white objects on a mostly dark/black background (the scrolling end credits of many movies being a common example). Some people perceive these rainbow artifacts all of the time, while others say they only see them when they let their eyes pan across the image. Yet others do not notice the artifact at all.
RGB
Red, Green, Blue; the type of monitor generally used with computers. RGB input or output often referred to as Computer input or output.
RCA connector
The connector used with VCRs and stereos for composite video signals and audio.
Real Time
The transfer of data that returns results so quickly that the process appears to be instantaneous.
Rear Projection
Projecting an image through a translucent screen material for viewing from the opposite side. This method of projection is the most
desirable for home theatre.
Refresh Rate
The rate at which the picture redraws itself in one second. Usually expressed in hertz (Hz).
Remote Mouse and Keyboard Control
Allows presenter complete control of computer presentation without direct access to projector. Allows for freedom of movement.
Resolution
Normally represented in width x height format referring to the number of pixels. e.g. FHD (1920 x 1080)
- Native resolution : Resolution of projector panels (Resolution of the picture actually seen on the screen).
- resolution : Resolution of the computer output signal.
If a computer signal at XGA resolution is fed into an SVGA projector, the projected picture will be seen at SVGA resolution. Usually, the input signal (native) from a computer is automatically
converted to the projector's own resolution (In this case, native XGA to projection SVGA). For this conversion process, re-scaling technology is applied.
RS-232C
A cable that connects a computer and its peripherals.
SVGA
Super VGA. Refers to a computer signal that is higher than the standard VGA resolution of 640 pixels by 480 lines with 16 or 256 colours.
SVGA graphics cards may output resolutions such as 1024 x 768, 1280 x 1024, 1600 x 1200 pixels or higher, with 16.7 million colours displayed.
Sabre
Subtractive Bi-Refringent Effect, a technology that allows two panels rather than three to generate the full 16 colour VGA palette.
The top panel provides white, magenta, blue, and cyan; the second brings colours from white through yellow and to red.
SECAM
The French broadcast standard (used in some other international markets) for video and broadcasting. Like PAL, SECAM is also a higher resolution than that of the US, until 2002.
Simulated colour
Also known as "false colour," or "colorized." Projected colours that are not the same as the original image. Some products
use a single, colorized LCD, often with purple for dark shades and yellow for light shades (purple background/yellow foreground). Therefore, what should appear on a screen as blue may be yellow,
green may be purple.
Sony Dynamic Digital Sound (SDDS)
An 8-channel sound format used in commercial movie theatres. The 8 channels are: Left Front, Left/Centre Front, Centre Front,
Right/Centre Front, Right Front, Left Surround, and Right surround. The sound is encoded in between the sprockets on the film. No follow-up has been announced for home theatre.
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 also referred to as Y/C. A composite signal, typically found coming out of an RCA jack on the back of most VCRs has the Y and C information
combined into one signal. The advantage of having luminance and chrominance separated is that a comb filter is not needed inside the video projector to separate the composite signal into the luminance
and chrominance signals. A comb-filter can reduce the sharpness of your video image
TFT
Thin Film Transistor. A technology used to make Active Matrix LCD panels wherein each pixel has its own transistor switch.
THX
Rumoured to stand for the Tomlinson Holman experience. Others say it named after George Lucas' first film, THX-1138. THX is a
set of standards by which laserdiscs and video tapes are made, as well as by which home theatre equipment is made. They are supposed to yield the highest quality in home theatre
THX Surround EX
This is built to further extend Dolby Digital Surround EX (DD-EX). This could be considered a 7.1 channel system. As opposed to DD-EX,
which has an added channel in the centre rear, THX-EX puts 2 more channels in the rear, so there is a front left, front right, front centre, listening position left, listening position right, rear left,
rear right. It uses Dolby Digital 5.1 as a base and matrixes in the extra 2 channels into the rear channels similar in fashion to Dolby Pro-Logic and Matrixed Surround. It is going to be available
exclusively in THX Ultra certified products.
Throw Distance
Length of the projection beam required for a projector to produce and image of a desired size.
TSTN
Triple Super Twist Neumatic. A technology used to make Active Matrix LCD panels where in each pixel has its own transistor switch.
UXGA
Resolution of a computer generated image. A UXGA projector will be able to display a 1600x1200 image from a computer running in a UXGA video mode. If the computer is not running in a UXGA video mode, typically the projector will resize the image to 1600 x 1200.
VGA Resolution
VGA Resolution normally refers to a 640 x 480 pixel display, regardless of the number of colours available. Originally VGA was 640 x 480
16 colours.
V-Sync
Vertical synchronization. A marker in a video signal for the beginning of a frame.
Varifocal Lens
A projector lens that has three focal elements contained in a single assembly.
Vertical Banding
Visible bands from top to bottom of the projected image that display a slight colour or brightness difference.
Vertical Resolution
The total number of horizontal lines that can be perceived in the vertical direction of the screen.
VGA Cable
Video Graphics Array. This is the standard interface for the IBM PS/2. It is the only analogue graphics card IBM has used
(other cards handle digital information) 720 x 400 in the text mode, graphics mode 640 x 480 resolution.
Video Compatibility
Ability of computers and projection units to transmit and receive data to read and/or project various video tape standards such as
NTSC, PAL, SECAM and S-VHS.
Whiteboard
Document-conferencing product that lets multiple users simultaneously view and make notes on a document with pens,
highlighters and drawing tools.
Widescreen
Term used to describe a picture in which the aspect ratio is wider than the NTSC standard of 4:3/1.33:1. Almost
all movies made nowadays are shot in some widescreen format. To solve the problem of different aspect ratios, several different techniques can be used. Among them are anemographic squeezing,
letterboxing, and Pan and Scanning.
XGA
Acronym for Extended Graphics Adapter. A standard introduced by IBM that includes VGA as well as resolutions up to
1024 pixels by 768 interlaced lines.
Y/C Connector
A 4-pin DIN connector used for high-end S-video sources.
Y-Cable
A cable that splits the monitor signal so that it will work simultaneously with both a monitor and a LCD panel
Zoom Lens
A lens with a variable focal length. This translates to being able to adjust the size of the image on a screen by
adjusting the zoom lens, instead of audio Visual Innovations to move the projector closer or further.