Abstract: A tapered waveguide optical mode transformer (20) includes a tapered core formed on a planar substrate structure (16). To vertically taper the core (21), steps (22) are etched into the top surface of the core. The steps have depths and lengths along the optical axis of tapered waveguide that are selected to transform the optical mode characteristics of a desired optical fiber to the optical mode characteristics of a desired planar waveguide. The core can also be tapered horizontally to form a 2-D tapered waveguide. The tapered waveguide can be integrally included in planar lightwave circuits (PLCs) to reduce light coupling losses between optical fibers and the PLC waveguides.

Abstract: A connector (100) for a plurality of optic fibers (106-107) includes a polymer layer deposited over the ends of the fibers at the face of the connector (100) to reduce insertion loss. The polymer layer (110) may be a single layer which encompasses all of the ends of the plurality of fibers (106-107), or separate layers deposited at each of the ends of the plurality of fibers. These layers may be configured to be generally square, rectangular, circular or elliptical. Additional layers of the polymer may be deposited on the face between alignment hole and the housing.

Abstract: A tapered waveguide optical mode transformer (20) includes a tapered core formed on a planar substrate structure (16). To vertically taper the core (21), steps (22) are etched into the top surface of the core. The steps have depths and lengths along the optical axis of tapered waveguide that are selected to transform the optical mode characteristics of a desired optical fiber to the optical mode characteristics of a desired planar waveguide. The core can also be tapered horizontally to form a 2-D tapered waveguide. The tapered waveguide can be integrally included in planar lightwave circuits (PLCs) to reduce light coupling losses between optical fibers and the PLC waveguides.

Abstract: Fiber optic connections are accomplished with passive alignment using a modular approach. An improved waveguide substrate has precisely aligned waveguides secured in place, including at an inlet channel, an outlet channel, or both. The waveguides need not extend beyond the face of the inlet or outlet location, and there is no need to have any unsupported fiber optic fibers connect to the waveguide substrate. When provided, a connector module or modules have fiber optic fibers having supported ends which precisely align with the waveguides of the waveguide substrate. Connecting pins typically are provided to insure alignment between waveguides and fibers is easily attained.

Abstract: Fiber optic connections are accomplished with passive alignment using a modular approach. An improved waveguide substrate has precisely aligned waveguides secured in place, including at an inlet channel, an outlet channel, or both. The waveguides need not extend beyond the face of the inlet or outlet location, and there is no need to have any unsupported fiber optic fibers connect to the waveguide substrate. When provided, a connector module or modules have fiber optic fibers having supported ends which precisely align with the waveguides of the waveguide substrate. Connecting pins typically are provided to insure alignment between waveguides and fibers is easily attained.

Abstract: Two techniques are disclosed for writing waveguides between laser diodes and an optical fiber such that the laser diodes are aligned with their respective waveguide facets. The first technique utilizes a light sensitive polymer, such as a ultra-violet (UV) cross-linkable polymer. A precision writing system locates the light emitting centers of the laser diodes and writes the waveguide circuit by exposing the waveguiding regions with the appropriate light. The unexposed areas of the core layer are developed with a solvent and removed. The entire device is then encapsulated with a low-index cladding polymer. The second technique utilizes an active polymer approach in which waveguide regions are formed when the writing beam aligns the dipole molecules in the polymer to cause a change in the refractive index of the polymer.

Abstract: Two techniques are disclosed for writing waveguides between laser diodes and a fiber channel such that the laser diodes are aligned with their respective waveguide facets. The first technique utilizes a light sensitive polymer, such as a ultra-violet (UV) cross-linkable polymer. A precision writing system locates the light emitting centers of the laser diodes and writes the waveguide circuit by exposing the waveguiding regions with the appropriate light. The unexposed areas of the core layer are developed with a solvent and removed. The entire device is then encapsulated with a low-index cladding polymer. The second technique utilizes an active polymer approach in which waveguide regions are formed when the writing beam aligns the dipole molecules in the polymer to cause a change in the refractive index of the polymer.

Abstract: An IMSM photodetector structure comprises a GaAs substrate, a buffer region grown on the substrate, an optically active absorbing layer of In.sub.0.42 Ga.sub.0.58 As grown on the absorbing layer. The buffer region includes in sequence a first layer of In.sub.0.23 Ga.sub.0.77 As, an In.sub.0.46 Ga.sub.0.54 As/GaAs superlattice, and a second layer of In.sub.0.23 Ga.sub.0.77 As. An interdigitated pattern of Schottky metal contacts is fabricated on the Al.sub.0.3 Ga.sub.0.7 As/GaAs superlattice. This structure is useful in fabricating long-wavelength, monolithic receivers based on GaAs MESFET technology since the optical and electrical characteristics of the structure are preserved during the thermal annealing cycle necesary in ion-implaned GaAs MESFET processes.

Abstract: Method of diffusing zinc into gallium arsenide and aluminum gallium arsenide. A wafer of gallium arsenide or aluminum gallium arsenide is placed in close proximity to a quantity of granular zinc gallium arsenide. The assemblage is heated in an open-tube furnace in the presence of flowing nitrogen to vaporize zinc whereby zinc diffuses into the gallium arsenide or aluminum gallium arsenide wafer without eroding the surface.