This post is by Phil Rhodes from ProVideo Coalition
Multicoloured LED movie light
Exactly how we get here is not as important as where we’re getting to.

Recently, the world has become very excited about the technologies underlying colour mixing LED lights. Here’s why we shouldn’t.

It’s been a while since LED lights have generally been able to do what they’re intended to do, and do it pretty well. Even the quest for higher power is starting to encounter the reality that the bigger they get, the smaller the market is, particularly once power levels exceed the capacity of the 15-amp NEMA connectors common in American domesticity. Other problems are simply hard to solve: finding two lights both described as “daylight” from different manufacturers which actually, visually match is still more difficult than we’d all like it to be.

The sunlit uplands are perhaps not quite as evenly sunlit as they should be, even if modern full colour mixing lights can solve the problem given a bit of tweaking. Overall, though, after a decade of madcap innovation, things are perhaps calming down a little.

Flexible LED textile lights on a trade show floor
“How I love my coat of many colours”

How colour mixing mixes colours

Consider the tendency for everyone to become concerned about the technology underlying colour mixing lights. No longer is it enough for lights to change colour; the manner in which they do so is now a point of contention. Lights based on red, green, blue and (one or two shades of) white LEDs now compete directly against those with red, green and blue plus amber, cyan, lime, and other things.

The problem is, that’s still too simple a way to describe the technology. Even if we have two lights using similar emitter configurations, there’s at least two major ways to create red, green and blue light with LEDs. Direct-emission types use different materials in the structure of (Read more…)