Absolute photometry has relative benefits for LED and SSL performance evaluation

The lighting industry is buzzing with excitement: solid-state lighting (SSL) is being celebrated as the solution to many of today’s energy and lighting application challenges. Available lumens per watt (otherwise known as the efficacy) of commercial white LEDs now far exceeds that of incandescent sources. In the laboratory, LEDs have been developed with efficacies similar to f luorescent and certain highintensity discharge (HID) sources.

However, we do not yet know to what extent such devices will become viable in the future as a replacement for existing high efficiency sources; issues such as manufacturability, cost and temperature stability must be addressed. Until these issues are sufficiently answered within the lighting industry, replacement costs and procedures will remain a reasonable concern to commercial purchasers.

Even if today’s SSL performance results are as good as the industry ever produces, a wide range of applications can be satisfied already. With performance increases actually coming at a surprising pace, and with anticipated reductions in manufacturing costs, LEDs certainly appear to be a major light source of the future.

+++++++

This article was published in the July/August 2008 issue of LEDs Magazine.

To read the full version of this article, please visit our Magazine page, where you can download FREE electronic PDF versions of all issues of LEDs Magazine.

You can also request a print copy of LEDs Magazine (available by paid subscription) and sign up for our free weekly email newsletter.