Christie Digital Systems CX67 Help Screen, Horizontal Frequency, Horizontal Offset, Hot Spot, Lux

	Appendix A: Glossary
Help Screen	' A display of help information regarding the current task or presentation.
Horizontal Frequency	' The frequency at which scan lines are generated, which varies amongst sources. Also
	called horizontal scan rate or line rate.
Horizontal Offset	' The difference between the center of the projected image and the center of the
	projector lens. For this projector, this value is expressed as the maximum percentage
	of the image that can be projected to one side of the lens center without degrading the
	image quality. Horizontal offset ranges can be affected by the type of lens in use, and
	whether or not the image is offset vertically at the same time.
Hot Spot	' A circular area of a screen where the image appears brighter than elsewhere on the
	screen. A hot spot appears along the line of sight and "moves" with the line of sight.
	High gain screens and rear screens designed for slide or movie projection usually
	have a hot spot.
Input	' A physical connection route for a source signal, described by a 2-digit number
	representing 1) its switcher/projector location and 2) its slot in the switcher/projector.
Input Signal	' Signal sent from a source device to the projector.
Interface	' A device that accepts an input signal for display by the projector.
Interlace	' A method used by video tape players and some computers to double the vertical
	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.
Keystone	' 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.
Lamp Flicker	' As the lamp ages, the shape of two anodes may changes from two points to a
	flattened state. When this occurs, the arc jumps across the gap from varying points.
	This is seen as image flicker. 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.
Linearity	' The reproduction of the horizontal and vertical size of characters and/or shapes over
	the entire screen.
Line of Best Viewing	' 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.
Loopthrough	' The method of feeding a series of high impedance inputs from a single video source
(Loopthru)	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.
Lux	' The amount of visible light per square meter incident on a surface.
	1 lux = 1 lumen/square meter = 0.093 foot-candles

RPMX/CX50/CX60/CX67 User’s Manual A-3