Terms relating to projectors are explained briefly below.

Aspect Ratio

The width-height ratio of a screen or image. A conventional television has an aspect ratio of 4:3, while that of a high definition wide screen television is 16:9.

Compressed Display

A high-resolution video signal displayed by compressing the image so that all lines and characters are shown.

Colour Temperature

A value expressing the colour of light, using the Kelvin (absolute) temperature scale. As light becomes redder, the temperature becomes lower, whereas bluer light is higher in temperature.

Resolution

The amount of detail of a display or image; more pixels per unit results in more sharply detailed images.

Gradations

The number of different colours that can be reproduced in screen images; the larger this number the smoother the colour rendition.

Colour Wheel

The colour palette inside a DLP projector. A conventional colour wheel consists of the three primary colours red, green, and blue, plus white. The adoption of BrilliantColor adds yellow, magenta, and cyan, which are intermediate hues of the three primary colours, thereby enabling the use of six colours for greatly improved colour reproduction.

Gamma Correction

A process that compensates for deviation in the relation of display brightness to input voltage. The parameter for gamma correction is called the gamma value.

Time-division Colour Multiplexing

A system for reproducing colours by high-speed switching of the three primary colours. To produce a large variety of colours the time allotted to projecting light in each colour is varied.

Contrast Ratio

The relative luminosity of the brightest to the darkest portions of an image. The higher this ratio, the clearer will be the images displayed due to the larger difference in brightness across any given image.

Centre-to-Corner Ratio (CCR)

The brightness of the image corners relative to the centre of the image. Normally, brightness increases toward the centre (also called centre-to-corner uniformity ratio).

Short-focus Lens

A lens with a short focusing distance; in the case of a projector, a short-focus lens makes it possible to project large images from short distance.

Projection Distance

The distance from the projector lens to the screen. Image size is in direct proportion to projection distance.

Lumen (lm)

A unit expressing the perceived amount of light (luminous flux). Projector luminance is measured by dividing the projected image into nine sections and finding the average lumens at the centre of each section.

BrilliantColor^™

Technology developed by the U.S. firm Texas Instruments for improving the colour reproduction capabilities of DLP projectors.

DLP^® (Digital Light Processing)

An all-digital display technology developed by the US firm Texas Instruments Incorporated.

Variable Illumination

A technology that controls the colour balance for different applications by adjusting the amount of illumination directed at each colour on the colour wheel. The colour balance can be adjusted by choosing colour modes on the projector.

XGA

A standard screen resolution of 1024 x 768 pixels.

SVGA

A standard screen resolution of 800 x 600 pixels.

SXGA

A standard screen resolution of 1280 x 1024 pixels.