Shack-Hartmann sensor based on a cylindrical microlens array

We present a Shack-Hartmann wavefront sensor (SHWS) based on a cylindrical microlens array as a device for measuring highly aberrated wavefronts. Instead of the typical spot pattern created by a conventional SHWS, two orthogonal line patterns are detected on a CCD and are superimposed. A processing algorithm uses the continuity of the focal line to extend the dynamic range of measurement by localizing the line, even if it leaves the CCD area confined by the corresponding microcylinder. The measurement of a wavefront from a progressive addition lens with an 80 lambda peak-to-valley value reveals the capabilities of the sensor.