Theory of color


Theory of color

The book of science

Tom Sharp

Isaac Newton optics

Theory of color


Reflecting telescope

Chromatic abberation

Newton explained that the differing refractions of colors in sunlight was responsible for the colors of primary and secondary rainbows, thus completing the inquiry begun by Alhazen in 1025.

Isaac Newton’s first reflecting telescope, finished in late 1668, had an object mirror with a diameter of 2 inches, a length of 6 and a quarter inches, and a small diagonal mirror to reflect the image to an eyepiece at the side of the telescope. He observed that it magnified 35 times.

William Herschel and William Parson followed Newton’s design and built reflecting telescopes with speculum mirrors, but with larger and larger diameters to gather more and more light.

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