You could say Newton was the first in discovering Visible light.In 1666, Isaac Newton took the first step toward trying to understand visible light when he passed sunlight through a rainbow prism and watched it break into a kaleidoscope of colors. Just like the wavelength differences between various parts of the electromagnetic spectrum, the array of colors comprising visible light are made of waves that have different lengths between successive crests or troughs. Red waves are the longest and violet waves are the shortest.

Who discovered Visible Light? When? And How?

William Herschel, the discoverer of Uranus, was the first to explore the region beyond the rainbow of visible light. In the year of 1800, he reported on experiments to determine the heating power of different colors, in which he let a spectrum of light fall on a set of thermometers. To his amazement, he found that the greatest heat to be found was produced off the red end of the spectrum where nothing was visible to anyone. “Radiant heat,” he proclaimed, “will at least partly consist, if I may be permitted the expression, of invisible light.” Herschel had discovered infrared radiation.

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