Cover Picture: Fabricating Microlens Arrays by Surface Wrinkling (Adv. Mater. 24/2006)

The unique lateral confinement of a swelling polymer network leads to surface wrinkles that define a multitude of surface structures, including microlens arrays (background). The versatility of this approach, which is reported on p. 3238 by Crosby and Chan, allows for the realization of a variety of functional devices on both planar and nonplanar surfaces, such as synthetic compound lens structures (see inset).