Moiré Patterns

DCS Code: 3B50.40 Last Updated: March 27, 2026
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Purpose

Visualizes two-source wave interference using overlapping transparencies printed with concentric rings. Students observe how moiré fringes representing constructive and destructive interference change as the "source" separation varies.

Top: a single transparency showing concentric semicircular rings representing wavefronts from one source. Bottom: two transparencies overlapped with centers offset, producing a moiré interference pattern with hyperbolic bright and dark fringes.
Figure 1:
Demo Apparatus