Reflected and Transmitted Newton's Rings
Newton's rings had been earlier observed by Robert Boyle and Robert Hooke, but the first experimental measurement of their radii was done by Isaac Newton. The theoretical explanation given by Thomas Young gives the relation between the wavelength of light , the radius of curvature of a given plano-convex lens, the squares of diameters of the circular interference rings, the refractive index of the region where the rings are formed and , the order of the ring. For Newton's rings formed from reflected light, the center ring is dark and the diameters of the dark and bright rings are given by and . For Newton's rings formed from transmitted light, the reverse is true. The center ring is bright and the relations for the diameters of the dark and bright rings are now and .
 A. N. Matveev, Optics, Moscow: Mir Publishers, 1988.
 F. A. Jenkins and H. E. White, Fundamentals of Optics, 3rd. ed., New York: McGraw-Hill, 1957.