The previous chapter examined wavefront sensor techniques that relied on measuring either local tilt (dW/dy) or the differential phase, dW, in the exit pupil. This chapter will concentrate on instruments that make measurements in the image plane. The generic name for this class of wavefront sensor is the Hartmann sensor. It is based on the classical Hartmann test. This was commonly used to measure the surface quality of astronomical telescope primary mirrors during polishing. For example, the 4 meter primary of the Mayall telescope atop Kitt Peak was tested in this manner.
Online access to SPIE eBooks is limited to subscribing institutions.