Eli5: What is the difference between natural and artificial light; and why can some plants thrive on artificial light?
In: 3
Natural light comes from things that get very hot, like the sun. That light has energy distributed over a range of different wavelengths that usually include all the visible wavelengths, some ultraviolet and some infrared.
The wavelengths of artificial light depend on the source of the light. An incandescent lightbulb will give you a similar spectrum to the Sun, because all it’s doing is getting hot enough to emit light.
Fluorescent lights emit very specific wavelengths only, which is why colors look weird under them. They put in enough wavelengths to fool your brain into thinking that they’re white, but they’re not really. A television also produces only three colors, and can make you think you’re seeing white.
LEDs also produce only specific wavelengths, based on the energy levels in the diode. They combine several of them to look white, and in fact it was a very big deal when they finally figured out how to make blue ones.
Plants are nature’s solar panels. They have specific molecules that are able to absorb specific amounts of energy that correspond to specific wavelengths of light, because the wavelength of light is its energy. If the light you shine on a plant doesn’t contain enough of the wavelengths it’s good at absorbing, the plant can’t get enough energy.
Latest Answers