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Submission + - Color Rendering Index (CRI) is not reliable when used for LED lamps 1

An anonymous reader writes: The Color Rendering Index (CRI) is a quantitative measure of the ability of a light source to reveal the colors of various objects faithfully in comparison with an ideal or natural light source. It has been found that the CRI is not reliable when used for LED lamps.

One of the problems is that a LED lamp can be tweaked to give a high CRI value while the color quality can still be bad. Also LED lamps with a good color quality with high saturated colors can result in a low CRI value.

The National Institute of Standards and Technology (NIST) has developed the Color Quality Scale (CQS) that it believes will offer a superior indication of color quality compared to CRI specifications.

Recently one of the largest independent lamp measurement labs in Europe started using the CSQ in all of their new lamp measurements. They also published an very informative video Color Quality Scale (CQS): Measuring the color quality of light sources which explains the problems with the CRI and why the CQS is better suited for LED lamps.

Submission + - New Tram uses induction technology ( 3

jeroen8 writes: "Trams all over the world could soon be operating without the eyesore of overhead cables according to Bombardier, the world's leading supplier of trams. Primove, Bombardier's new tram system, uses induction technology for the transfer of electric power. This contact-less technology is five to six percent more efficient than other technologies in current use, says Bombardier. Amsterdam council (The Netherlands) has already shown serious interest. The Primove tram is also fitted with an integrated MITRAC energy saving system installed on its roof. This system consists of capacitors which store energy when the tram brakes and allows this energy to be used for acceleration. Tests conducted on a "light-rail" system in Mannheim since 2003 have shown that up to thirty percent less energy is required, greatly reducing costs and emission levels."

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