Question

what is the Newton's fringe are called?​

Answer 1

Answer:

Newton's rings is a phenomenon in which an interference pattern is created by the reflection of light between two surfaces—a spherical surface and an adjacent touching flat surface. It is named for Isaac Newton, who investigated the effect in his 1704 treatise Opticks.This results in a pattern of concentric bright and dark rings, interference fringes. Newton's rings seen in two plano-convex lenses with their flat surfaces in contact. ... In white light, the rings are rainbow-colored, because the different wavelengths of each color interfere at different locations.

Answer 2

Rings are fringes of equal thickness. ... If the lens plate system is illuminated with monochromatic light falling on it normally, concentric bright and dark interference rings are observed in reflected light. These circular fringes were discovered by Newton and are called Newton's rings.