Christie DS+5K User Manual page 124

Appendix A: Glossary
Input Signal
Interface
Interlace
Keystone
Lamp Flicker
Linearity
Line of Best Viewing
LiteLOC
Loopthrough
(Loopthru)
Luminance
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Input
A physical connection route for a source signal, described by a 2-digit number
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representing 1) its switcher/projector location and 2) its slot in the switcher/projector.
' Signal sent from a source device to the projector.
A device, such as the Serial Digital Input Module, that accepts an input signal for
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display by the projector.
A method used by video tape players and some computers to double the vertical
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resolution without increasing the horizontal line rate. If the resulting frame/field rate is
too low, the image may flicker depending on the image content.
Keypad
A small push-button device for controlling most projector settings and operation. For
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more information, refer to 3.3, Using the Keypad.
' A distortion of the image which occurs when the top and bottom borders of the image
are unequal in length. Side borders both slant in or out, producing a "keyhole" shaped
image. It is caused when the screen and lens surface are not parallel, or (in "X"
models) by poor Keystone adjustment.
As the lamp ages, the shape of two anodes may changes from two points to a flattened
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state. When this occurs, the arc jumps across the gap from varying points. This is seen
as image flicker. Turning the Lamp Conditioning feature ON will pulse the lamp and
gradually "condition" the two anodes back to two points. Lamp Conditioning may
take seconds, minutes or hours to reach full effectiveness. NOTE: Lamp flicker can
occur at any time in the lamps life. The length of time, over which flicker may occur
varies considerably and unpredictably. This behavior is inherent in UHP lamps.
The reproduction of the horizontal and vertical size of characters and/or shapes over
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the entire screen.
' When light from a projector is incident on a screen, the light reflects from the screen
such that the angle of reflection equals the angle of incidence. The Line of Best
Viewing is along the line of reflection.
A Christie software feature where samples of output light from a projector trigger
 '
automatic adjustments in the lamp ballast power in order to maintain a constant light
output over time. Also known as brightness tracking.
' The method of feeding a series of high impedance inputs from a single video source
with a coaxial transmission line in such a manner that the line is terminated with its
characteristic impedance at the last input on the line.
Lumen
The unit of measure for the amount of visible light emitted by a light source.
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' The signal representing the measurable intensity (comparable to brightness) of an
electronic image when the image is represented as separate chrominance and
luminance. Luminance also expresses the light intensity of a diffuse source as a
function of its area; measured in lumens or candles per square foot (1 lumen per
square foot = 1 footlambert). SMPTE RP 98 calls for a luminance of 12 to 22
footlamberts for theatre screens. See: Footlambert.
Lux
The amount of visible light per square meter incident on a surface.
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1 lux = 1 lumen/square meter = 0.093 foot-candles