Texas Instruments DW30 Input Signal, Interface, Interlace, Keypad, Linearity, Loopthrough, Lumen

Appendix A: Glossary

Input	f 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	f Signal sent from a source device to the projector.
Interface	f A device, such as the Serial Digital Input Module, that accepts an input signal for
	display by the projector.
Interlace	f 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	f A small push-button device for controlling most projector settings and operation. For
	more information, refer to 3.3, Using the Keypad.
Keystone	f 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.
Linearity	f The reproduction of the horizontal and vertical size of characters and/or shapes over
	the entire screen.
Line of Best Viewing	f 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	f 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	f The unit of measure for the amount of visible light emitted by a light source.
Luminance	f 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: Foot-lambert.
Lux	f The amount of visible light per square meter incident on a surface.
	1 lux = 1 lumen/square meter = 0.093 foot-candles
Menu	f A list of selectable options displayed on the screen.
NTSC Video	f A video output format of some video tape and disk players. There are two types of
	NTSC (National Television Standards Committee) video: NTSC 3.58 and NTSC 4.43.
	NTSC 3.58 is used primarily in North America and Japan. NTSC 4.43 is less
	commonly used.
Optical Aperture	f Commonly called an iris, the optical aperture when adjusted affects true contrast.
Optical Screen	f A type of rear-projection screen which re-directs light through the screen to increase
	image brightness in front of the screen. Screen gain is usually greater than 1 but
	audience viewing angles are reduced.
A-4 Christie DS+60/DW30/Matrix 3000 User’s Manual		013-100149-02 Rev. 1 (01/07)