That portion of the entire electromagnetic spectrum which is visible to human eyes as light of various color. The visible spectrum occupies the region of the electromagnetic spectrum from between 400 to 780 nanometers, between infrared and ultraviolet. The whole visible spectrum, when each wavelength of light is present in equal quantities, is only discernible as white light. It is only the selective absorption and emission of some of these wavelengths by other objects and substances that cause us to see colors.
|