Enhancing the spatial resolution of a two-dimensional discrete array detector

We present a technique for enhancing the resolution of a two-dimensional de tector by processing images that have been subsequently acquired shifted by a fraction of a pixel with respect to each other. Possible limitations due to the intrinsic spectral broadening of the actual signals and to sources of error in the procedure have been analyzed. The results prove that the re construction algorithm is insensitive to high uncertainties in the relative subpixel displacements of the single images and to a low signal-to-noise r atio. Experimental tests have been performed with a detector with pixel siz e 25 x 25 mu m(2). Images of fine wire mesh grids with periods 100 and 50 m u m and of a 10-mu m-wide slit are presented. The reconstructed images show improved resolution of the profiles of the targets corresponding to 1/4-pi xel sampling. (C) 1999 Society of Photo-Optical Instrumentation Engineers. [S0091-3286(99)00210-X].