I recognize that sRGB will never be able to do a perfect job, but it seems like it has to be possible to do decently well.
(What do I need this for? I design electronics. I use LEDs as indicators. I like to show the true color of the LED in my schematics and documentation, as best I can. And I try to never use the same color twice, in small and bespoke things, so there's less risk of indicator confusion, which means I've often got a lot of funny colors around.)
Coming up with a matching color by hand can give a decent result, so this is not solely sRGB being crap.
Using those in images however would be another can of worms, you'll need some kind of physics-based rendering with good HDR tone mapping, as the human perception of light-emitting object against reflective background is highly non-linear.
For your use case it would probably be better to develop a standardized testing setup and just take RGB or XYZ coordinates from an image taken with a calibrated camera. Something like this:
* "standard gray" material surface
* a hole for LED with some kind of light pipe of standard shape
* uniform diffuse lighting of intensity computed to be proportional to your LED power measured in a standard way.
In this way it should be possible to create a catalog of LEDs useful for designing products.
bergsteiger•2mo ago
We used some of this data to trace progress in LED development for our recent Nature Energy paper on technology spillovers in solid-state lighting: https://doi.org/g9kcjd.