Adaptive silicone-membrane lenses: planar vs. shaped membrane

We compare the performance and optical quality of two types of adaptive fluidic silicone-membrane lenses. The membranes feature either a homogeneous thickness, or it is shaped resulting in an inhomogeneous cross-section. The lens systems incorporate a piezo actuator which is operated in a regime of plusmn40 V. The shaped membrane lenses show lower wave front errors than the planar ones, down to 24 nm. However, the system with a planar membrane achieves a larger refractive power ranging from +19 to -14 dpt. It also shows a shorter full scale response time (t_planar = 23.9 ms) compared to the shaped membrane (t_shaped = 35.4 ms).