The effect of lenslet resolution on the accuracy of ocular wavefront measurements

The most critical element in a ocular Shack-Hartmann wavefront sensor is the microoptic lenslet array. This array largely determines the accuracy of the wavefront measurement and the dynamic range of the measurements. This paper discusses the details of how the density of the lenslet array affects the accuracy of the wavefront measurement. We briefly discuss wavefront reconstruction, which is the mathematical process that takes the output from the lenslet array and reconstructs the input wavefront. We compare the two primary methods of reconstruction, the zonal fit and the modal fit. We also show how a denser array can be designed to have a better dynamic range.