What is moiré?
A moiré pattern is an interference pattern created, for example, when two grids are overlaid at an angle, or when they have slightly different mesh sizes. The drawing above shows a moiré pattern. The lines could represent fibers in moiré silk, or lines drawn on paper or on a computer screen. The nonlinear interaction of the optical patterns of lines creates a real and visible pattern of roughly horizontal dark and light bands, the moiré pattern, superimposed on the lines. More complex moiré patterns are created if the lines are curved or not exactly parallel. The term originates from moire (or moiré in its French form), a type of textile, traditionally of silk but now also of cotton or synthetic fibre, with a rippled or ‘watered’ appearance.