| 摘要 |
A laser comprises a lasing medium (10) having a slab geometry, a waveguide arrangement either side (12,14) of the slab, mirrors (16,18) forming an unstable sub-resonator acting in a plane perpendicular to the waveguide, and a concave mirror (22) arrangement acting on light incident on it launched from the waveguide, and thereby transformed from waveguide light to free space light, to redirect and retransform a portion of said light to be re-entrant waveguide light constituting the unstable sub-resonator round-trip self-replicating light. The unstable sub-resonator preferably includes a folding mirror (20) to direct light towards the concave mirror (22), and the concave mirror is preferably partially transmissive. <IMAGE> |
