RESUMO
We describe the implementation of a technique for achieving image superresolution using a fully connected network of simple processors operating in an iterative mode. We show that an updating scheme can be specified that ensures convergence for the serial (asynchronous) updating case. With the appropriate hardware, parallel (synchronous) updating becomes of particular interest because of the potential for accelerated convergence; it is this approach that we envisage implementing in optical hardware. For this case also, we present a convergent scheme that can be related to a regularized form of the Gerchberg-Papoulis algorithm.
RESUMO
A method is described of applying a variable frequency-shift to a laser beam, by means of Bragg cells, in which the direction of the output diffracted beam is unaffected by the magnitude of the applied shift. Applications of the technique to reference-beam and Doppler-difference forms of laser anemometry are discussed together with methods of obtaining increased dynamic range.