Surface profiling and characterization of microlenses utilizing a Shack-Hartmann wavefront sensor

We report on the characterization of microlenses utilizing the three-dimensional (3D) surface profile obtained from a Shack-Hartmann wavefront sensor. This method can be applied to most types of microlenses, especially liquid ones. Both a solid and a liquid microlens were characterized. The surface data was analyzed and then exported into Zemax to compute their optical properties. The wavefront error of the liquid lens tested increased from 0.44 to 2.41 waves as its focal length was tuned from 10.1 to 4.3 mm. The surface profiles can also be used to study the effect of gravity on microlenses and surface wetting for optimizing the lens fabrication procedure.