Abstract: Alternative laser structures, which have potentially the same tuning performance as (S)SG-DBR and GCSR lasers, and a fabrication process which is similar to that of the (S)SG-DBR laser, are presented. The advantage of these structures is that the output power does not pass through a long passive region.

Abstract: Alternative laser structures, which have potentially the same tuning performance as (S)SG-DBR and GCSR lasers, and a fabrication process which is similar to that of the (S)SG-DBR laser, are presented. The advantage of these structures is that the output power does not pass through a long passive region.

Abstract: Alternative laser structures, which have potentially the same tuning performance as (S)SG-DBR and GCSR lasers, and a fabrication process which is similar to that of the (S)SG-DBR laser, are presented. The advantage of these structures is that the output power does not pass through a long passive region.

Abstract: An optical device comprising an optical waveguide (13) on a substrate (11) which over part of its length forms one of a stack (15) of coupled optical waveguide sections of the same length, the stack being of a length such that a light wave of predetermined frequency propagating along the waveguide (13) to enter the stack (15) at one end thereof produces light waves at the other end of the stack which are substantially in phase adjacent each waveguide section. The device finds particular application for coupling light from a substrate waveguide into another waveguide, e.g. an optical fibre (27), off the substrate (11).

Abstract: A semiconductor diode laser array device 1 capable of emitting a high optical power in a narrow beam, the device 1 comprising a surface emission multiridge waveguide structure in which emission can take place from a surface 4 occupying both a longitudinal and a lateral dimension of the device, the dimension in each case being much greater than the emitted light wavelength. Stability in one of said dimensions may be maintained by an array design having a spaced arrangement of laser elements positioned such that the optical field in one element partly overlaps that of a neighboring element. Preferably, the sum of the propagation constant and the coupling parameters to the neighboring elements equals the same value for all the elements in the array.