1976/09/01 by George W. Sutton, Melvin M. Weiner, Siva A. Mani
Materials Science · Engineering · #Optical Coatings and Gratings #Near-Field Optical Microscopy #Electromagnetic Simulation and Numerical Methods
paper · doi:10.1364/ao.15.002228
Theoretical Fraunhofer diffraction patterns are presented for uniformly illuminated square apertures with noncentered square obscurations. The energy within a given subtended solid angle in the far field is calculated. It is shown that the cornered-off-axis obscuration provides much more far-field energy in a given spot size than the centered obscuration for the same clear aperture area and total energy, for example, 82% more far-field energy in the first Airy square for 50% obscuration, thus providing superior performance for practical systems.