Please select a letter for terms starting with that letter:

- I -

IC
Acronym for Integrated Circuit.

ICIA
Acronym for International Communications Industries Association.

ICON
In a graphical user interface, an on-screen symbol that represents a program file, date file or some other computer entity or function.

ICWK (Internal Computer Wiring Kit)
ICWK kits provide interfacing signals for computers and terminals with no external video display output. Internal video monitor signals are routed externally from the terminal, usually to a 9 pin connector. From the 9 pin connector, a short cable is included with the kit for signal transfer to the interface 9 pin connector input.

IDTV
Acronym for Increased Definition Television - Example; scan doubling.

ILA™
Image Light Amplifier - Used in their large screen projectors, a Hughes/JVC device that uses low-intensity images to modulate high-intensity light through a liquid crystal layer.

Impedance (Z)
The opposition or "load" to a signal. Circuits that generate audio or video signals, are designed to work with a certain "load", or impedance. Typical video impedance's: 75 ohm or High Z. Also see High Impedance and Low Impedance.

Impedance-Matching
When connecting devices in a system, it is important that the impedance specifications are adhered to. If impedance's are not matched, there could be undesirable results, such as: loss or distortion of the original signal, reflections, etc.

Interactive Video
The fusion of video and computer technology. A video program and a computer program running in tandem under the control of the user.

Interface
A device or module that operates as a link between other dissimilar modules, usually because those modules cannot communicate directly with each other. An interface acts like a translator, or interpreter, and could be in the form of hardware and/or software. A Video Interface allows computer-video to be used by large screen video displays.

Interlaced
The process of scanning whereby the alternate lines of both scanned fields fall evenly between each other every 1/30th of a second.

Interleaving
The process of assigning consecutive physical memory addresses alternately between two memory controllers in order to increase transfer rate.

Information Processing
The processing of data representing information and the manipulation of the processed data.

Information Retrieval
The ability to choose interactively any data segment and have a computer locate it.

Infrared (IR)
A type of wireless transmission standard that uses infrared (invisible) light. IR light can travel about 30 feet.

Integrated Circuit
Combining many circuits into one module.

Interpolation (Signal Processing)
(Definition from Tektronix) Generally speaking, a "connect-the-dots" processing technique to estimate what a fast waveform looks like based on only a few sampled points. More specifically, Interpolation refers to the way the oscilloscope calculates values for record points when the oscilloscope cannot acquire all the points for a complete record with a single trigger event. That condition occurs when the oscilloscope is limited to real time sampling and the time base is set to a value that exceeds the effective sample rate of the oscilloscope. The oscilloscope has two interpolation options: linear or sin(x)/x interpolation. Linear interpolation calculates record points in a straight-line fit between the actual values acquired. Sin(x)/x computes record points in a curve fit between the actual values acquired. It assumes all the interpolated points fall in their appropriate point in time on that curve.

Input
Data transferred from its source to a computer. To transmit information from its source to a computer.

Integrated Services Digital Network
A CCITT standard for integrated transmission of voice, video and data. Bandwidths include: Basic Rate Interface - BR (144 Kbps - 2 B & 1 D channel) and Primary Rate - PRI (1.544 and 2.048 Mbps). Integrated Services Digital Network. A set of protocol and interface standards that effectively constitute an integrated (voice, video, and data) telephone "network." These standards promote global availability and compatibility of ISDN products and services. The two types of ISDN discussed in this Guide are Basic Rate Interface (BRI) and Primate Rate Interface (PRI). ISDN BRI (ISDN Basic Rate Interface) is the interface to connect the desktop to the digital long distance network. ISDN BRI provides two 64Kbps B ("bearer") channels to carry information content, the voice, video and data substance of a transmission. A separate 16Kbps D ("data") channel is used for call setup and signaling. ISDN BRI is often called "2B+D" ISDN, for its combination of two B and one D channel. This service is marketed and supported by the LECs. ISDN PRI (Primary Rate Interface) is the ISDN equivalent of a T-1 circuit. It provides 23B+D (in North America) or 30B+D (in Europe) running at 1.544 Mbps and 2.048Mps, respectively. Each channel (time slot) is 64Kbps. One channel is reserved as the D channel; the other 23, as bearer channels (23+D).

Interactive
Employing the active participation of the user in determining the flow of the multimedia program. An interactive system can exchange formation with the user, process the user's input, and act in response.

Interactive Video (IV)
Combining video and computer technology under the control and direction of the user. In interactive video, the user's actions and decisions determine the sequences.

Interface
To connect normally incompatible components so that the signal from one is readable by the second. Often transmitting one standard or language to a device which recognizes another, different standard or language.

Interlacing
A technique used for the display of live video and some computer graphics. Originally intended to allow use of lower cost monitors. Most video display devices write the picture to the screen using vertically stacked horizontal lines representing thin horizontal slices of the intended image. With interlacing first the odd lines are written to the screen from top to bottom, then the even lines are filled in. Interlacing is used to reduce flicker which is caused when the first field fades while the next is being written, resulting in half faded lines next to freshly drawn lines.

IO
Input/Output - Refers to the flow of information or signals (in and out) with respect to a computer or other device.

IP Address

IP Addressable Projector
Configured projector participating on the LAN.

IR (Infrared)
A type of wireless transmission standard using infrared light. Infrared or non-visible electromagnetic heat from lightsources.

IRE
Acronym for Institute of Radio Engineers.

IRE Scale
An oscilloscope scale that applies to composite video levels. 1 Volt Peak - Peak Video is divided up into 140 IRE units. This is done to make numbers for luminance levels easier to communicate. The amplitude of the video signal from blanking (zero volts) to peak white is 0.714286 volts or 100 IRE units. Synchronization signals extend from blanking to - 1.285714 volts/ - 40 IRE units.

ISDN
Acronym for Integrated Services Digital Network.

IS0 9000
Quality standard (International Standards Organization).

IS0 14000
Quality standard (International Standards Organization).

ITU
International Telecommunications Union; one of the specialized agencies of the United Nations and founded in 1865 before telephones were invented as a telegraphy standards body.

IEC
Interexchange Carrier. Long-distance carrier providing service between local area exchanges (LECs). AT&T, MCI, and GTE-Sprint are IECs. The services an IEC provides may be interstate or intrastate, as long as it's between local areas.

IXC
Interexchange carrier, long distance service providers in the U.S. that provide inter-LATA service.

[back to top]