Abstract: Uniformity of optical coupling of optical elements such as star couplers and splitters is improved by heat treatment which causes dopants in the core of an optical fiber to diffuse into material from the cladding layer of the optical fibers from which the optical element is formed, resulting in a substantially homogeneous interior region of the star coupler or splitter. Increased lossiness of the optical element thus formed may be limited by termination of the heat treatment before dopant diffusion reaches equilibrium throughout the fibers so that a portion of the cladding layer of the fibers remains surrounding the substantially homogeneous region where the fibers have been fused together.

Abstract: An improved optical fiber for laterally directing a laser beam having a waveguide including a tip for communicating electromagnetic radiation in a propagation direction to the tip of the waveguide, a transmitting surface on the tip of the waveguide, a reflecting surface on the tip of the waveguide for internally reflecting electromagnetic radiation communicated by the waveguide in a direction lateral to the propagation direction toward a particular area on the transmitting surface, and wherein the particular area and the reflecting surface are disposed so that substantially all electromagnetic radiation reflected by the reflecting surface is incident on the particular area at below a critical angle for transmission through the transmitting surface in the lateral direction.

Abstract: A strain relief boot (10) in combination with a connector (15). The strain relief boot (10) has a body (11) having a rigid portion (12) and a flexible portion (13). A center bore (14) extends through the body (11) and the connector (15) is slidingly disposed in the center bore (14). The body (11) has an inner wall (20) surrounding the center bore (14). A plurality of spaced-apart ribs (21) are formed on the inner wall (20) of the rigid portion (12). Each rib (21) has a top surface (22) and a pair of adjoining sidewalls (23). The ribs (21) extend inwardly into the center bore (14) and grip the connector (15) with a friction fit, retaining the strain relief boot (10) on the connector (15).

Abstract: An optical component mounting substrate which comprises grooves for holding optical fibers, other grooves for optical components being inserted and optical waveguides is produced with a press molding process. A mold having convex and/or concave surface profiles which are corresponding to the grooves and the optical waveguides to be formed on a surface of the optical component mounting substrate is used as a die in the press molding process. The surface profiles of the mold are precisely transferred onto the surface of a transparent glass base substrate, thereby forming the optical component mounting substrate having a desired surface configuration including the grooves and the optical waveguides. Optical fibers are aligned along the grooves and fixed by a light-curing adhesive.

Abstract: An optical coupling device for coupling light into a selected output fiber. The input fiber is optically aligned with one of a plurality of output fibers via a reflector. By rotating a reflector about an axis, the input light beam can be reflected to a selected output fiber. The input fiber and all the output fibers are in fixed position relative to each other.

Abstract: A light waveguide is guided in the longitudinal direction over a defined length together with a filling compound, which are to be introduced into an outer envelope. The velocity of the light waveguide is subsequently decelerated to a lower value due to the reduction of velocity of the filling compound as it enters into the tubular envelope and, thus, the change in velocity converts the excess length of the waveguide into a non-straightline course or a serpentine configuration within the filling compound in the envelope.

Abstract: The presence of (typically unintended) birefringence in single mode optical fiber can severely limit the usefulness of the fiber for, e.g., high bit rate or analog optical fiber communication systems, due to the resulting polarization mode dispersion (PMD). It has now been discovered that PMD can be substantially reduced if, during drawing of the fiber, a torque is applied to the fiber such that a "spin" is impressed on the fiber. Desirably the torque is applied such that the spin impressed on the fiber does not have constant spatial frequency, e.g., has alternately clockwise and counterclockwise helicity. At least a portion of optical fiber according to the invention has spin alternately clockwise and counterclockwise.

Abstract: The capacity of a multi-mode optical fiber system, such as a local area network, is increased by selectively propagating only higher-order modes through the multi-mode fiber. Because only a small number of higher-order modes are propagated, pulse spreading induced by modal dispersion is minimized, and the bandwidth of the multi-mode fiber is increased. Because of the reduced modal dispersion, higher-order modes are recovered from the multi-mode fiber in accordance with the invention without filtering the output of the fiber. This renders the system less vulnerable to mechanical perturbations that are known to reduce the bit error rate of systems requiring filtering. Thus, by propagating only higher-order modes in this manner, the "bandwidth-distance" product of the multi-mode fiber is significantly increased.

Abstract: An optical integrated circuit is disclosed. The optical integrated circuit includes: a dielectric waveguide having at least a waveguide layer for transmitting light in a first direction; a first reflector for reflecting the light in a substantially opposite direction to the first direction, the first reflector being formed on an end face of the waveguide layer; a grating coupler having a grating for diffracting at least a part of the light in a second direction which is different from the first direction, the grating coupler being formed at a surface of the waveguide layer; and a light detector for detecting the diffracted light, the light detector being optically connected with the dielectric waveguide.