Abstract

Radiation parameters of 2D-arrays of waveguide CO₂-lasers synchronised by in-cavity spatial filter method are investigated. The dependencies for phase-locking efficiency and for axial brightness of far-field array radiation rationed to maximal value versus of number N of single lasers in an array, filter parameters and conditions of excitation are received. For all N phase-locking efficiency decreases if filter transparency also decreases because influence increases of additional in-cavity radiation losses by filter introduced [1]. Efficiency dependencies against N for fixed filter have the maximum weakly expressed. Its appearance is connected with competing influence of two effects: decreasing of in-cavity losses and increasing of initial scatter of lazing frequencies of single lasers in an array when the number of single lasers increases. Second effect at large N dominates and leads to efficiency decreasing. Increase of initial scatter of lazing frequencies when number N increases leads also to monotone decrease of the far-field axial brightness. In addition, axial brightness of radiation for periphery groups of single lasers within of the common aperture of 2D-array decreases in comparison with axial brightness for the central group containing the same number of lasers. It may be explained by decreasing of optical coupling coefficient on the array periphery and, as consequence, by narrowing of the frequencies locking range.

© 2000 IEEE