Abstract: A double heterostructure injection laser has its active layer close to the surface. A rib protruding from that surface provides lateral optical confinement of laser radiation propagating in the active layer under the rib.

Abstract: A double heterostructure injection laser has its active layer close to the surface. A rib protruding from that surface provides lateral optical confinement of laser radiation propagating in the active layer under the rib.

Abstract: An integrated optical circuit provides a heterostructure injection laser wherein the optical resonator is spaced apart from the active optical region of the laser. One embodiment of the invention provides a second low loss waveguiding layer at a different level from the active layer for convenient optical connections between the laser and the optical circuit.

Abstract: This invention relates to an optical waveguide switch and directional coupler providing variable coupling between two optical fibers. The coupler is fabricated in semiconductive material such as GaAs or GaAlAs. A double heterostructure is used having a higher index of refraction middle layer. Optical fibers are inserted in channels in the semiconductive material. Varying the reverse bias across the heterostructure junctions located in the material between the channels electrically changes the refractive index of the material and alters the coupling between the fibers. The device is applicable to switching in optical communication systems.

Abstract: Antireflection dielectric coatings on the output face of an injection laser provide a negative electric vector amplitude reflection coefficient which increases the obtainable power output. Like coatings are applied to the opposite reflective face. The output layers are preferably three quarter-wavelength coatings of titania, silica and titania. The opposite reflective layers are two quarter-wavelength coatings of titania and silica and an outer metallic layer of aluminum. Silicon monoxide can also be used in place of titania.