Addressable Microlens Array to Improve Dynamic Range of Shack–Hartmann Sensors

In this paper, we have demonstrated an addressable array (5-by-5) of high-quality microlenses suitable for application in a Shack-Hartmann (SH) sensor in a microoptical system. Specific lenses in the array can be addressed using a new selection scheme (that we have designed, built, and tested) in which the mechanical resonant frequencies of individual lens-support carriages are varied. Thus, by changing the frequency of the drive voltage, we require only two electrical connections per row in the lens system to identify the selected lens by its resonating focal image. We show that using this lens-identification method will allow us to improve the dynamic range of SH sensors by a factor of 12-46 above values reported for conventional SH designs