User Manual

The New Color Standard
Faced with absence of reliable color information from projector users and purchasers, in 2009 the
National Institute of Science and Technology (NIST) issued a scientific paper on Color Brightness. It
stated that in addition to the typical white light brightness rating of display devices, there was a need to
provide "an equivalent measurement that will better describe a projector's color performance when
rendering full color imagery.”
After extensive research and evaluation, the Society for Information Display (SID) concluded that a color
brightness standard was relevant in the display industry. This scientifically valid measurement tool
(referred to by the SID as Color Light Output), is designed to provide consumers with a specification to
allow them to easily evaluate color brightness, a critical aspect of image quality.
The International Committee for Display Metrology (ICDM), a division of the SID, was tasked with
developing the new standard. Composed of display experts, electrical, mechanical, software and optical
engineers, physicists, vision scientists, and professionals in many display-related disciplines, the ICDM,
along with the Video Electronics Standards Association (VESA) worked for two years to create the
International Display Measurement Standard, or IDMS. Released in May, 2012, the comprehensive
IDMS publication provides measurement methodologies for displays, including projectors, and for the
first time, included Color Light Output.
Color Light Output (CLO), also known as Color Brightness, is a specification that provides information on
a projector’s ability to accurately reproduce color. Current brightness specifications only measure the
total amount of white light projected, as stated in lumens. The new Color Light Output or Color
Brightness specification measures red, green, and blue light, testing each on a nine-point grid, using the
same methodology as that used to measure the brightness of white light.
The electronic version of the IDMS is available on the ICDM website (http://www.icdm-
sid.org/downloads/) and includes test patterns, reporting templates, and other utilities for the new
Display Measurement Standards.
Understanding Color Light Output
Projector manufacturers typically provide information about resolution, White Light brightness and
contrast ratio as metrics to define projector performance. But as none of these specifications directly
address a projector’s color performance, the Color Light Output metric complements existing
specifications and gives buyers an accurate way to evaluate competitive models more thoroughly.
Measured using a similar approach to the tests for White Light Output, Color Light Output provides a
simple, accurate and easy-to-understand metric to evaluate a projector’s color brightness.
The traditional brightness (or White Light Output) specification measures the total amount of white light
projected in lumens on a nine point grid, but it does not measure color.