making different color led lights

Hey everyone,

How do they make different color led's? I am planning on building my own lights (more for fun I am currently using 3 400w digis) the plan is to make several single plant lights to cover roughly1.5sq/ft each and lets say around 35 watts each using a combination of 1w and 3w diodes, the problem I am having is finding led in very specific colors. I was thinking that maybe the reason leds are not as good in practice as they are in theory is a combination of light penetration and too narrow of light spectrum.
So using 3w leds for chlorophy A would give good penetration, and using 1w for other peaks such as chlophyll b, beta caroten, phycoerythrin, and phycocyanin, and also adding a uvb 275nm diode in for thc improvementmight help. My thought is maybe light is like nutrients you cant just grow with N-P-K you also need the micro's, so an array of different color leds will give you the main colors needed but also several other colors of photosynthesis respones.

If anybody has any input on this I would appreciate it.

The different "colors" of LED's are expressed in terms of the wavelength they produce, in "nano-meters" (that's really friggin' small!).

You can think of an indevidual LED as a little "Electronic Jello Cup". The "cup", itself, is a tiny reflector that focuses the light in a forward direction. The "Jello" is made up of various different chemical compounds that determine the wavelength (or color) of the LED. In other words - a different "flavor of Jello" will produce a different colored light! When a small current of electricity is passed through the device, it becomes a semi-conductor and reacts by emitting light. Pretty cool - huh?

So, to make a long story short. The different colors of LED's are acheived by useing different recipes of chemical compounds in the manufacturing process.

I share your opinion that a wider range of wavelengths are needed to make LED grow lights a real player in the field, but the industry keeps turning out the sammo-sammo. Just Chlorophyll-A and Chlorophyll-B have 4 seperate spiked wavelengths - let alone all the other pigments that require thier own wavelengths to photosynthesize. DON'T GET ME STARTED!

UV-B producing LED's used to be rather expensive, I imagine they still are! Most supplimental UV light is provided by "Reptile Lights" from a pet store these days.

Anyway - good luck with your project!