Wafer-scale fabricated thermo-pneumatically tunable microlenses

• DOI: 10.1038/lsa.2014.26
• Publication Date: 2014-02-28T07:25:08Z
• Authors: Wei Zhang; Hans Zappe; Andreas Seifert
• Keywords: Microlens; Silicone oil; Fluidics; Polydimethylsiloxane

We have developed a self-contained, liquid tunable microlens based on polyacrylate membranes integrated with compact on-chip thermo-pneumatic actuation fabricated using full-wafer processing. Silicone oil is used as the optical liquid, which pushed or pulled into lens cavity via an extended microfluidic channel structure without any pumps, valves other mechanical means. The heat load generated by thermal actuator physically isolated from chamber. back focal length may be tuned infinity to 4 mm maximum power consumption of 300 mW. principal application fine tuning length, for time constants small 100 ms are suitable. Scientists in Germany designed fluid-based widely length. Developed Wei Zhang and co-workers at University Freiburg, consists circular fluidic chamber filled silicone sandwiched between glass substrate flexible membrane. fluid connected air entire housed protective silicon micromachined frame. lens' values applying voltage heating element Expansion heated forces more chamber, causing membrane deform thus shape change.