Propagation 2011 - What do LEDs provide?
Light choice
Given I wanted to have the most efficient lights, and that I also had an understanding of their light performance, I decided to use LEDs.
LED technology
It had been many years since I designed electronic circuits incorporating LEDs. The technology has moved on significantly since then. I am familiar with the low power red indicator LEDs - typically about 50mW of electrical power. You can now get LEDs in many colours - one breakthrough has been the invention of blue LEDs. The picture below shows the spectra for red, green-yellow and blue LEDs.
So this explains the design of LED grow lamps advertised as using lots of low power LEDs - they are using different LED colours to attempt to create the chlorophyll absorbance curve. However can they adequately match the peaks and provide sufficient moles / day?
White LEDs
Another breakthrough has been the invention of white LEDs - see the picture below, where we can see the peak in the blue region, a dip in the green region and a lower peak in the red region. .