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Making Moiré

overlapping blue line patterns on a white background.
A blue and white pillar in a glass and white foyer, with a sign at the top saying 'Making Moire'.

Overlapping line patterns create interference or Moiré pattern illusions.

How it works

Spin the outer sheath of the pillar and watch how the patterns form.

Things to try or ask around the exhibit

Which lines create the strongest interference patterns?

Background

When the two line patterns overlap, you may see new, different patterns called moiré (“mwah-ray”) or interference patterns.

Moiré patterns form when a line on the front surface covers some of the clear space behind to make a thicker, darker line. The dark and clear spaces vary in thickness to form moiré patterns.

Finding the science in your world

Moiré patterns can be printed ‘invisibly’ onto valuable documents (such as money). If someone tries to scan or photocopy the document, the copy is distorted and unusable.