This paper describes the Wavelens technology: a new type of varifocal liquid lenses actuated by
electrostatic parallel plates. The main technological steps involved in the fabrication process are discussed and
the influences of the membrane material, the electrode size and composition (rigidity and stress) on the optical
performance are evaluated in detail. The varifocal lenses were characterized extensively using wave-front
measurements. Optical powers of 11m<sup>-1</sup> at 9V (16m<sup>-1</sup> at 10V) are measured on lenses with optical diameters
of 3mm. The influence of the electrode size on the optical power is analyzed giving basic design rules for the
device performance optimization. No significant optical quality degradation was observed with a low wave
front error (<0.15μm) measured on the varifocal lenses.