Tilted pillars on wrinkled elastomers as a reversibly tunable optical window.

We demonstrate the design and fabrication of tilted micropillar arrays on wrinkled elastomeric poly(dimethylsiloxane) as a reversibly switchable optical window. Upon re-stretching the as-prepared (opaque) film to the original pre-strain, the grating color is restored and ∼ 30% transmittance is recovered. Further stretching beyond the pre-strain makes the film more transparent. This process is fully reversible and repeatable for many cycles.