Application of Shack-hartmann Wavefront Sensors to Optical System Calibration and Alignment

While Shack-Hartmann wavefront sensors are commonly used for adaptive optics, they have many other applications. The modern Shack-Hartmann wavefront sensor is compact, rugged, and insensitive to vibration, and has fully integrated data acquisition and analysis. Furthermore, even wavefronts of broadband sources that cannot normally be tested with interferometers can be measured with Shack-Hartmann wavefront sensors. The instrument also provides information about the optical system performance, including peak-to-valley (PV) wavefront deviation, RMS wavefront error, the modulation transfer function (MTF), and the point spread function (PSF). Since the difference of two wavefronts is easily computed, the effect of individual optical elements on a complex optical system can be examined.