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GLOSSARY
Ambient
light: The
surrounding light of a particular scene picked up by a
television camera.
Aperture:
The adjustable lens diaphragm that rises, with a wider
or smaller opening, to regulate the amount of light that
reaches a television camera or other image sensor device.
Bandwith:
A range within a band of wavelengths, frequencies,
or energies; the data transfer rate of an electronic communications
device.
Camera
sensor: The device for capturing light and transmitting
a resulting impulse; a detector of light that affects
or controls camera operation.
Coaxial
cable: A transmission line that consists of a tube
of electrically conducting material held in place by insulators
that is used to transmit television signals of high frequency.
Electron
tube: An electronic device in which conduction by
electrons takes place through a vacuum or gaseous medium
within a sealed glass or metal container and which has
various uses based on the controlled flow of electrons.
Gain:
The increase (as of voltage or signal intensity) caused
by an amplifier.
Integrated
circuit: A miniature interconnected circuit made up
of many electronic and semiconductor components, all contained
in a single , discrete electronic element.
Neutral
density filter: A group of gray filters with graded
intensities, used to minimize contrast and cut down exposure
of a camera sensor to light.
Photoconductivity:
Electrical conductivity that is affected by exposure to
electromagnetic radiation, as in light.
Resolution:
Ability of a lens to render fine line detail in a photographic
image. In TV, the maximum number of discernible lines
of a television image.
Satellite:
Communication device in orbit above the earth that
is used to distribute television and radio signals from
one geographic location to another.
Scanning:
Horizontal electron beam sweep moving over a camera
pickup tube.
Scanning
rate: Inches per second covered by the scanning beam
for television.
Semiconductor:
Any of a class of solids whose electrical conductivity
is between that of a conductor and that of an insulator
in being nearly as great as that of a metal at high temperatures
and nearly absent at low temperatures.
Solid-state:
Utilizing the electric, magnetic or optical properties
of solid materials; using semiconductor devices rather
than electron tubes.
Solid-state
circuit: A circuit that is complete unto itself, and
is manufactured from one discrete unit of calibrated semi-conductor
material.
Synchronizer:
A voltage pulsation that determines scanning synchronization;
a device for making signals recur or operate at the same
time.
Television
camera: Device that changes light from a scene into
an electric signal, called a video signal, which varies
depending on the strength or brightness, of light received
from each part of the scene.
Vidicon:
Small television camera tube that uses the principle of
photoconductivity to form an image over a surface. Used
widely in the early days of television.
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