There is more to color than a visual experience.
As we know, color is part of light and light is an electromagnetic wave. Electromagnetic waves are waves that are capable of traveling through a vacuum and are capable of transporting energy through the vacuum of outer space. Electromagnetic waves are produced by a vibrating electric charge and as such, they consist of both an electric and a magnetic component. Electromagnetic waves exist with an enormous range of frequencies. This continuous range of frequencies is known as the electromagnetic spectrum.
Light is a small portion of the electromagnetic spectrum, which also includes X-rays, microwaves and radio ways. Electromagnetic waves move like waves and that is just like the waves on a body of water. Electromagnetic waves travel in a straight line as they radiate out in all directions from the source.
The distance between two crests of a wave (called the wavelength) determines which type of wave it is. Television and radio waves are over a metre apart. The gamma and cosmic rays are very close together, only billionths of a metre apart. Around the middle of the spectrum is the tiny portions we experience as visible light.
What we call the visible light region is the very narrow band of wavelengths located between the infrared region and the ultraviolet region. That does not mean that other electromagnetic waves are invisible. They are invisible to us. Our eyes can see only this very narrow band. Since this narrow band of wavelengths is visible to humans we refer to it as the visible light spectrum. The term "light," refers to a type of electromagnetic wave that stimulates the retina of our eyes. Thus, we are referring to visible light, a small spectrum of the enormous range of frequencies of electromagnetic radiation.
Within the visible spectrum, waves also have different lengths. The longest waves are at the red end of the spectrum, and the shortest at the purple end, with the other colors falling in between in order of their wavelengths. So each individual wavelength within the spectrum of visible light wavelengths is representative of a particular color. What we see as color is the light of a particular wavelength striking the retina of our eye, which is then sent to our brain as a signal to be interpreted. We actually don’t see with our eyes, but with our brain.
These pure colors are referred to as “rays” by color therapists. We don’t perceive infrared and ultraviolet light, but other creatures such as snakes and honey bees can see it. It was an English physicist and mathematician, Isaac Newton, who showed that light is comprised of colors by shining it through a prism. The light will separate into its different wavelengths and will thus show the various colors it is made of.
We call this separation of visible light into its different colors dispersion. Dispersion of visible light produces the colors red (R), orange (O), yellow (Y), green (G), blue (B), and violet (V).
As we can see, there is no black present in dispersion because black is not a color. Black is merely the absence of light, the absence of the wavelengths of the visible light spectrum. So when we are in a room with no lights and everything around us appears black, it means that there are no wavelengths of visible light striking our eyes as we look around.
We are able to perceive this narrow range of wavelengths. Other parts of the spectrum with long wavelengths, such as microwaves, or short wavelengths, such as X-rays, destroy living things.
In conclusion, we must remember that color is not what we see. It is an electromagnetic wave propagating in the electric field, which transports energy. It is this energy that is influencing us. Thus, we should work on developing the science of color.