Also Newton rings. Concentric coloured rings which appear when two pieces of glass or clear plastic are pressed together. A problem with glass negative carriers and a phenomenon discovered by English physicist Sir Isaac Newton (1643-1727).
The rings appear when theres a tiny air gap between two pieces of clear material. Light rays encounter destructive interference if the gap is of a certain size relative to the wavelength, resulting in the effect. Its most pronounced if a convex lens is pressed up against a perfectly flat glass surface.
cf. anti-Newton glass, light interference, negative carrier, popping.
Entry last updated 2002-05-09. Term 832 of 1487.
Previous term: neutral density filter.
Next term: NIC.