Extraction of high-quality beams from narrow annular laser sources

We have analyzed the propagation properties of the field produced by circul ar arrays of cohere nt optical sources, obtaining the conditions for the ge neration of good-quality global beams. Such conditions can be obtained by t he use of resonators based on the Talbot effect. This appears to be a pract ical method for the construction of simple, low-cost resonators for compact diffusion-cooled high-power lasers with annular format. Low-loss annular T albot cavity configurations have also been studied. (C) 1999 Optical Societ y of America. OCIS codes: 140.3300, 140.3410, 140.3290, 140.3470, 140.4780.