Ultra-fast, high-quality and highly compact varifocal lens with spherical aberration correction and low power consumption.

We present a highly compact and fast varifocal lens with aspherical tunability based on an active piezo-glass-piezo sandwich membrane. Using an optimized geometry, improved fabrication and compliant elastomer structures together with an index-matched optical fluid, we achieved an outer diameter of just 9 mm (10 mm packaged) for a clear aperture of 7.6 mm. The range of the focal power was -7 m ^-1 to +6 m ^-1 , with a wavefront error around 100 nm and a response time between 0.1 and 0.15 ms.