Image Intensifier an electronic device which is used to amplify small amounts of light into usable amounts of light to produce a video picture.
Image Sensor indicates the type of semiconductor which handles video processing inside of a camera. Older CCTV cameras used tubes to process light information. CMOS and CCD image sensors are the most widely available for security cameras in today's market. CCD cameras provide by far the highest quality video of any type of image sensor.
Impedance the total opposition offered by a device to the flow of an alternating current. Measured in Ohms. CCTV industry has standardized 75-ohm impedance.
Incident Light the light that falls directly on an object.
Interference Extraneous energy which tends to interfere with the reception of the desired signals.
Interlacing PAL video signals transmit odd and even lines alternately. This is a 2:1 interlace. The two sets of lines are combined to form each single frame.
Interlaced Scanning a scanning process for reducing image flicker in which the distance from centre to centre of successively scanned lines is two or more times the nominal line width, and in which the adjacent lines belong to different fields.
Interline Transfer a technology of CCD design, where rows of pixels are output from the CCTV camera. The senso's active pixel area and storage register are both contained within the active image area. Differs from frame transfer where all active pixels are moved to a storage register outside of the active area.
Internal Sync Devices with internal sync, have an internal crystal to provide sync pulses, without needing reference from any external device.
INT Internal sync mode that sets to internal 2:1 interlace.
Input Voltage indicates the type of electrical current (AC or DC) and the voltage required to safely and effpixelsly power a device.
IP: Internet Protocol a set of rules to send and receive messages at the Internet address level.
IPCCTV Internet Protocol Closed Circuit Television
IP Waterproof Rating (IP66 - IP68) IP ratings are a BSi standard measurement for how waterproof something is. Many cameras or camera housings are designed for outdoor use, and therefore need to be waterproof to some degree. The details of the tests are defined in BS EN 60529 : 1992. The IP number has two digits, and optional letters after them. These have the following meaning:
Code |
Description |
First Digit
0, 1, 2, 3, 4, 5, 6 |
Protection against ingress of foreign objects:
- 0 means non-protected
- 1 means Protected against solid objects over 50mm diameter
- 2 means Protected against solid object over 12mm diameter
- 3 means Protected against solid object over 2.5mm diameter
- 4 means Protected against solid object over 1mm diameter
- 5 means Protected against dust (Ingress of dust is not totally prevented)
- 6 means dust tight and protects against access with a wire.
|
Second Digit
0, 1, 2, 3, 4, 5, 6, 7, 8 |
Protection against ingress of water:
- 0 means non-protected
- 1 means Protected against solid objects over 50mm diameter
- 2 means Protected against direct sprays at an angle up to 15° from vertical
- 3 means Protected against direct sprays at an angle up to 60° from vertical
- 4 means Protected against direct sprays from all directions- limited ingress permitted
- 5 means Protected against low pressure jets from all direction- limited ingress permitted
- 6 means Protected against strong jets from all directions- limited ingress permitted
- 7 means Protected against effects of immersion from 15cm - 1m, duration of test 30 minutes
- 8 means protects against continuous immersion in water.
|
First Additional Letter
A, B, C, D |
- A means protects against access with back of hand.
- B means protects against access with finger.
- C means protects against access with tool.
- D means protects against access with wire.
|
Supplementary Letters
H, M, S, W |
See BS EN 60529 |
E.g.,
IP66 - Total protected against dust and strong jets from all directions.
IP68 - Total protected against dust and long periods of immersion under pressure.
For further information or to get a copy of the standard, see the BSi website at www.bsi-global.com or www.bsi.org.uk.
IR Infrared Light is a frequency of light which is lower than the human eye's visible spectrum (in the range of 850 ~ 950 nanometers). Color cameras CANNOT use infrared light whatsoever. However, this special band of light CAN be detected by most any monochrome CCD camera. Therefore, a black and white video camera in combination with Infrared lighting can see in pitch dark conditions where the human eye is unable to distinguish anything. An Infrared light source appears just the same as any visible light source on a black and white camera image. Infrared lighting for monochrome cameras should in no way be confused with new FLIR (forward-looking Infrared) spotting scopes or cameras which produce a grainy, green-tinted picture and do not require additional Infrared lighting sources.
IR Infrared Wavelength indicates the specific frequency of light (measured in nM - nanometers) an Infrared illuminator emits.
IR Illumination Range indicates the effpixels range at which a monochrome CCD camera can utilize the Infrared light from an illuminator and create an image. Eyespyvideo.com offers several camera models with built-in Infrared illuminators capable of casting light more than 40 feet in front of the camera. 40+ feet is therefore the IR illumination range for those cameras. Just like visible lights, more intense Infrared lighting sources will provide a larger illumination area and range.
Iris This is a mechanical device that adjusts to vary the amount of light passing through the lens of a camera. An adjustable opto-mechanical aperture built into a camera that controls the amount of lights coming through the lens.
ISDN Integrated Service Digital Network. A set of standard for digital transmission over ordinary telephone copper wire. |
