VARIATIONS ON A HARTMANN THEME

We explore modifications of the classical Hartmann wavefront sensing technique that can be used to improve its accuracy, dynamic range, and spatial resolution. We describe a differential sensor with variable sensitivity. We review the use of various possible Hartmann masks and discuss their interferometric properties. We propose the use of Fourier analysis and show its relationship to moire methods. We finally envisage the possibility of mapping both the slope and the total curvature (Laplacian) of the wavefront with the same setup.