Newton’s Rings
Interfering reflection in the air space between glass surfaces. Newton observed these patterns reflected between a lens and a plane surface (hence the name: “Newton’s Rings”), but it was not understood how reflections of light can produce the dark fringes. 150 years later Thomas Young’s postulated light waves, and how they can destructively and constructively interfere. Different path lengths are created by the non-flat surfaces interfere at different wavelengths, producing colored fringes. —Samuel F. Pellicori, Senior member OSA