Methods for operating lasers with single high-order modes and for efficient coherent addition of several laser distributions will be described. These methods are based on introducing intra-cavity phase elements, so as to obtain compact, stable, and practical laser configurations that can generate high output powers concomitantly with good output beam quality. The principles of the methods, the new laser configurations that include the phase elements, the experimental procedures and results with solid state and fiber lasers will be presented.
Asher A. Friesem received B.Sc. and Ph.D. degrees from the University of Michigan in 1958 and 1968, respectively. From 1958 to 1963 he was employed by Bell Aero Systems Company and Bendix Research Laboratories. From 1963 to 1969, at the University of Michigan's Institute's of Science and Technology, he conducted investigations in coherent optics, mainly in the areas of optical data processing and holography. From 1969 to 1973 he was principal research engineer in the Electro-Optics Center of Harris, Inc., performing research in the areas of optical memories and displays. In 1973 he joined the staff of the Weizmann Institute of Science, Israel and was appointed Professor of Optical Sciences in 1977. He subsequently served as Department Head, Chairman of the Scientific Council, and Chairman of the Professorial Council. In recent years his research activities have concentrated on new holographic concepts and applications, optical image processing, electro-optic devices, and new laser resonator configurations. He has served on numerous program and advisory committees of national and international conferences. Among other posts, he served for many years as a Vice President of the International Commission of Optics (ICO) and Chairman of the Israel Laser and Electro-Optics Society. He is a Fellow of OSA, a Life Fellow of IEEE, a Member of SPIE, and a Member of Sigma Xi. Over the years he has been a Visiting Professor in Germany, Switzerland, France and the U.S.A., has authored and co-authored more than 250 scientific papers, co-editor of four scientific volumes, and holds 30 international patents.
A map to the AV Williams Building [showing nearby parking] can be found on the UMD parking map