Introduction

Signal recovery and synthesis is concerned with methods for obtaining the best estimate of an image from the data and constraints at hand. It is an area that is important to many fields of optics, as well as a broader constituency due to its interdisciplinary nature; examples include digital image reconstruction from Fourier intensity measurements, superresolution, tomographic reconstruction and deconvolution/deblurring. Applications cover both incoherent and incoherent imaging; crystallography; tomography and inverse scattering.

This focus issue of Optics Express reflects presentations at a recent OSA Topical Meeting held in June 2005. The papers presented herein cover diverse applications from superresolution, recovery of spatial frequency information beyond the measured bandwidth, to image reconstruction in the absence of any optical elements. The advantage of on-line publication is the presence of non-print media. This is well-illustrated with a movie of the application of a motion-dewarping estimator to point-by-point imaging of the living retina.

These papers were invited for this focus issue and I would like to thank the authors for their contributions to this dynamic field with such high quality results.

Julian C. Christou University of California, Santa Cruz