How bright is that light?

Searching for a bright light for your application, you visit a few web sites and try to make sense of the specs. It’s one thing to find the geometry you need but how do you tell how bright the light will be? There are several ways of measuring light intensity, so if you’re going to use science rather than trial-and-error you’ll want to understand what they mean.

Daryl Martin and John Merva of Advanced Illumination have done a great job of ‘illuminating’ this murky topic, (you like that pun?) in, “Light Intensity,” (Vision & Sensors, June 29, 2009.) It’s not exactly poolside reading, so you’ll need to go through it a couple of times, but it will help you with interpreting the spec sheets put out by each vendor.