Title:
Engineering Specification: 12.1-inch AMLCD Monitor
Page
24 of 27
Document Number
: 023-0284-00
Revision:
A
10.0
GLOSSARY OF TERMS AND ABBREVIATIONS
Aspect Ratio
:
The ratio of width to height of a display surface. The standard television aspect ratio is 4:3.
Back Porch
: The portion of a composite display signal which lies between the trailing edges of a horizontal
sync pulse and the corresponding blanking pulse.
Black Level
: The display-signal level corresponding to a specified limit for black peaks.
Blanking
: The process of decreasing (or increasing) the display-signal level so that no visible retrace will
appear on the display screen.
Blanking Level
:
The level of a composite display signal which separates the range containing display
information from the range containing synchronizing information. Also called the pedestal level, or blacker-
than-black.
Brightness
: A psycho-physiological attribute of visual perception in which a source appears to emit or reflect
more or less light. Its psycho-physical, photometric equivalence is luminance.
Candela-per-meter-squared [cd/m
2
]
: The international unit of luminance (nits).
Candle Power
: Luminous intensity expressed in candelas.
CIE
: Abbreviation for the Commission Internationale de l'Eclairage, formerly referred to as the International
Commission on Illumination (ICI).
Chrominance
: The colormetric difference (dominant wavelength and purity) between any color and a
reference "white" of equal luminance. In three-dimensional CIE color space, chrominance is a vector which
lies in a plane of constant luminance.
Chromaticity
: The color quality of light which is defined by its dominant wavelength and purity (see
Chrominance).
Chromaticity Value
: The scalar value of any one component of a three-component color (also called a
tristimulus value). The unit value of each component is the amount of that component added to the other two
components to produce a reference "white".
Color Data
: The programmed values which determine the amplitudes of the signal which drive a color
display.
Color Saturation
:
A psycho-physiological measurement of the degree to which a color appears to be free of
white light.
Color Temperature
: The temperature to which a black body must be heated to produce a color matching that
of the source.
Contrast
: The ratio between the maximum and minimum luminance values of a display.
dB (Decibel)
: A measure of the ratio of two signals. The dB value is 20 x log
10
of a voltage or current ratio or
10 x log
10
of a power ratio.
