Electrowetting for Tunable Microoptics

The design, fabrication, and optical properties of tunable liquid microoptical components based on electrowetting are presented. Two optical microsystems are discussed: a single liquid microlens with tunable focal length, centered and stabilized in a micromachined positioning structure, and laterally repositionable tunable liquid microlens arrays. The latter employs electrowetting for lateral movement as well as focal length tuning of the optical elements. Through the use of novel microstructuring techniques, a high positioning accuracy may be achieved with low electrode count.