Abstract: In a multi-layered dielectric mirror the higher refractive index layers comprise ZnS and the lower refractive index layers comprise a composite of approximately 95%MgF2 and 5%CaF2 by mole fraction. In one embodiment, the fluoride layers are e-beam deposited from an essentially eutectic melt of the two fluorides. In another embodiment, the semiconductor surface on which the mirror is formed is protected by an aluminum borosilicate glass layer. Application of the invention to the design and fabrication of VCSELs is also described.

Abstract: In order to make traffic signs, information signs or advertising signs sufficiently visible in poor lighting conditions, a self-illuminated system with a fiber-optic lighting device is provided. The signs and billboards to be illuminated include one or more preferably plastic panels functioning as a display device arranged over each other, in which light is propagated from the fiber-optic device parallel to a display plane. Transparent information or signaling entities are provided on or in the panel or panels. In order to improve the quality of the illumination and to lower the manufacturing costs, the fiber-optic device is assembled in a modular manner from a plurality of standardized parts for standard fiber-optic systems according to display system requirements and includes multi-arm light guides, light outlet bodies for the multi-arm light guides acting as optical attachments for adjusting propagation angles for the light so that light intensities over the entire angular range are uniform.

Abstract: The invention relates to an optical waveguide having a core made of one member selected from halide glasses, chalcogenide glasses and oxyhalide glasses. This one member is doped with both of erbium and cerium. The invention further relates to a 1.5 &mgr;m-band optical amplifier having the optical waveguide for amplifying the light. Due to the doping of both erbium and cerium, it becomes possible to provide a highly efficient optical amplifier having low noise and wide band. With this, it becomes possible to construct an optical communication network having high credibility, high capacity and high speed.

Abstract: A dispersion compensating device for compensating dispersion of signal light. In an optical fiber communication system, distortion of optical pulse waveform caused by wavelength distortion is compensated. The signal light is inputted through an input port, propagating through a dispersion compensating fiber through a port of an optical circulator. The signal light is reflected by a totally internal highly reflective surface, again propagating through the dispersion compensating fiber reciprocally, thus being outputted through an output port of the optical circulator. Since the signal light propagates through the dispersion compensating fiber reciprocally, the dispersion compensating fiber is capable of compensating dispersion with one-half the length of the conventional example.

Abstract: Fiber Bragg grating coupled light sources can achieve tunable single-frequency (single axial and lateral spatial mode) operation by correcting for a quadratic phase variation in the lateral dimension using an aperture stop. The output of a quasi-monochromatic light source such as a Fabry Perot laser diode is astigmatic. As a consequence of the astigmatism, coupling geometries that accommodate the transverse numerical aperture of the laser are defocused in the lateral dimension, even for apsherical optics. The mismatch produces the quadratic phase variation in the feedback along the lateral axis at the facet of the laser that excites lateral modes of higher order than the TM00. Because the instability entails excitation of higher order lateral submodes, single frequency operation also is accomplished by using fiber Bragg gratings whose bandwidth is narrower than the submode spacing. This technique is particularly pertinent to the use of lensed fiber gratings in lieu of discrete coupling optics.

Abstract: The invention provides a semiconductor laser module with an electronic cooling device prevented from experiencing a lowering of the optical frequency response characteristic level in a band used for public communications. By changing the inductance of the ground line between module package and chip-mounted carrier of the semiconductor laser module, the resonance frequency of a resonance circuit made up by including the ground line is shifted so as to deviate from the frequency band of public communications used by a modulation signal transmitting device.

Abstract: An attaching arrangement for attaching, to a communications apparatus container box, an optical cable case which includes a case body for accommodating an optical cable and a case end portion attached to the case body. The attaching arrangement includes: a first rotary hinge having a first rotary hinge axis for rotatably attaching the case end portion to the container box around the first rotary hinge axis; and a second rotary hinge having a second rotary hinge axis perpendicular to the first rotary hinge axis for rotatably attaching the case end portion to the container box around the second rotary hinge axis. In a preferred implementation, the attaching arrangement further includes: a slide rail slidably attached to an inner surface of the container box along a direction parallel to the second rotary hinge axis so that the slide rail is slidable from an inside of the container box to an outside of the container box and from the outside of the container box to the inside of the container box.

Abstract: A waveguide device for optical signals in an optical communication system relies upon photonic bandgap material to guide the optical signal via a plurality of pathways. A two-dimensional photonic bandgap material is formed in a planar slab of dielectric medium by a two-dimensional lattice in which discontinuities in the lattice region define waveguides. A waveguide array formed in the device allows multiple Mach-Zehnder interferometer devices to be constructed including small radius turns without significant losses. An optical signal equalizer formed of such a device relies upon the transfer function defined by a multiple arm Mach-Zehnder having arms of different length. By applying controlled modulation to propagation through the arms, an adaptive equalizer is formed. The adaptive equalizer has application in correcting gain tilt in line amplifiers of optical communications systems.

Abstract: A VCSEL comprises separate current and optical guides that provide unique forms of drive current and transverse mode confinement, respectively. In one embodiment, the optical guide comprises an intracavity high refractive index mesa disposed transverse to the cavity resonator axis and a multi-layered dielectric (i.e., non-epitaxial) mirror overlaying the mesa. In another embodiment, the current guide comprises an annular first electrode which laterally surrounds the mesa but has an inside diameter which is greater than that of an ion-implantation-defined current aperture. The current guide causes current to flow laterally from the first electrode along a first path segment which is essentially perpendicular to the resonator axis, then vertically from the first segment along a second path segment essentially parallel to that axis, and finally through the current aperture and the active region to a second electrode.

Abstract: A composite cable for conducting electrical and optical signals is disclosed. The composite cable comprises a cable housing having a ribbon slot with an optical fiber ribbon arranged in the ribbon slot. The cable housing also has a tubular opening with a multiplicity of copper pairs arranged therein for conducting electric power through the oval slotted composite copper pair and optic ribbon cable, for providing strength to the cable, and for bending without elastic recovery to shape the cable. The composite cable may also include a removable compression cap for covering the ribbon slot.

Abstract: An alignment adapter for use with a multi-fiber, optical connector that is in the form of a substantially planar slab having a central opening for receiving a connector therethrough. The slab includes a pair of alignment apertures on opposing sides of the central opening that are positioned in a defined spatial relationship with the fibers held in the multi-fiber connector. According to an aspect of the invention, the alignment adapter includes a pair of alignment rods held in the alignment apertures that are used to convert an optical connector into a male type connector. According to another aspect of the present invention, a connector is disclosed having a plurality of channels for holding optical fibers and a pair of alignment apertures positioned adjacent to the fiber holding channels in a defined spatial relationship.

Abstract: An optical fiber module for facilitating changing part of an existing electrical signal transmission system to an optical transmission system. The fiber module includes an electric connector, a laser diode (LD) semiconductor IC, an LD module, a photodiode (PD) semiconductor IC, a PD module, an optical connector, a printed circuit board, a cover, and a shielding portion. In one embodiment, the printed circuit board has a constricted portion between first and second areas of the cover. In another embodiment, the circuit board is flexible and can be folded at a central portion. The optical fiber module is easily attachable and detachable from the outside of a computer without requiring a mother board to have optical fibers mounted thereon.

Abstract: A split sleeve 1 for optical connectors is provided, which may be constructed from a single part with a reduced cost and which permits retention forces on larger and smaller ferrules to be easily adjusted in uniform manner. The split sleeve 1 includes a cylindrical member made from a metallic material, such as phosphor bronze or stainless steel, representing an appropriate spring-back action. A slit is extended in the axial direction from one end to the other end of the cylindrical member. One end portion 1a of the cylindrical member on one side of an intermediate portion is configured to have a larger diameter, while the other end portion 1b of the cylindrical member on the other side of the intermediate portion is configured to have a smaller diameter.

Abstract: Disclosed are ferrules for an optical fiber connector provided with an insertion hole for setting an optical fiber in position and methods for the production thereof. The ferrule is formed of an amorphous alloy possessing at least a glass transition region, preferably a glass transition region of not less than 30 K in temperature width. Preferably the ferrule is formed of an amorphous alloy having a composition represented by the following general formula and containing an amorphous phase in a volumetric ratio of at least 50%:X.sub.a M.sub.b Al.sub.cwherein X represents at least one element selected from the group consisting of Zr and Hf, M represents at least one element selected from the group consisting of Mn, Fe, Co, Ni, and Cu, and a, b, and c represent such atomic percentages as respectively satisfy 25.ltoreq.a.ltoreq.85, 5.ltoreq.b.ltoreq.70, and 0<c.ltoreq.35. Such a ferrule can manufactured with high mass-producibility by a metal mold casting method or molding method.

Abstract: A snap lock connector particularly well suited to optical fiber systems, is composed generally of a receptacle body having a socket and a plug body having a number of collet fingers. A first fiber optic cable is connected to a first ceramic terminus having a first face inside the socket. A second fiber optic cable is connected to a second ceramic terminus having a second face inside the collet fingers. The first ceramic terminus is fixedly connected to the receptacle body in axial alignment therewith; and the second ceramic terminus is resiliently biased with respect to the plug body in axial alignment therewith. The exterior of the receptacle body has a circumscribed groove for engaging the tips of the collet fingers. The plug body has a locking sleeve slidably mounted thereon for being selectively slid over the collet fingers.

Abstract: Apparatus (20) for aiming and projecting laser radiation emitted from an output-face (56) at an output-end (52) of an optical-fiber transmitter (54), includes a target (26) surrounding the output-end of the optical-fiber transmitter and held in a fixed relationship therewith. One or more light sources (46) illuminate the target with visible light such that the target directs at least a portion of the visible light in the emission direction of the laser radiation whereby when the optical-fiber transmitter is directed toward a surface, the visible light directed by the target indicates an incidence region of the laser radiation on the surface. The apparatus optionally includes an optical system (27) arranged to project a visible image (72) of the target and an image (74) of the output-face of the optical fiber transmitter. The degree of focus of the visible target-image on the surface corresponds to the degree of focus of the laser radiation on the surface.

Abstract: It is an object of the invention to provide a light-receiving module, in which alignments of optical axes of optical fibers and photodiodes can be easily carried out and efficiencies of light incidences on the photodiodes are not influenced by imperfections in a fabrication process. The light-receiving module according to the invention is composed of a photodiode-forming member and an optical fiber-supporting member. The photodiode-forming member is composed of light-receiving surfaces of the photodiode formed thereon and bank-shaped optical fiber-fixing guides for guiding the optical fibers along both their sides. The optical fiber-supporting member is composed of optical fiber-fixing grooves for fixing parts of the optical fibers near their output ends and reflector surfaces for changing directions of the lights emitted from light-emitting surfaces of the optical fibers.

Abstract: A highly efficient channel drop filter. The filter employs a coupling element including a resonator-system between two waveguides, which contains at least two resonant modes. The resonator-system includes one or more interacting resonant cavities which in addition to being coupled to the waveguides, can also be coupled directly among themselves and indirectly among themselves via the waveguides. Each component of the coupling element can be configured or adjusted individually. The geometry and/or dielectric constant/refractive index of the resonator-system are configured so that the frequencies and decay rates of the resonant modes are made to be substantially the same. The filter can achieve 100% signal transfer between the waveguides at certain frequencies, while completely prohibiting signal transfer at other frequencies. In exemplary embodiments, the filter is configured with photonic crystals.

Abstract: A cable sleeve for light waveguides is constructed as a flat plate member in which a circular groove extends and has inlets extending tangentially from the groove. The cable sleeve can receive excess lengths of the cable as well as splices which excess lengths and splices are received in the circular groove.

Abstract: A variable optical attenuator controllably filters an optical signal after the signal has been expanded and collimated. The optical signals are optionally expanded and refocused by a single GRIN lens, the signal passing through a variable filter between the GRIN lens and a reflector, and again between the reflector and the GRIN lens. Both the input and output fibers can be held within a single sleeve in alignment with the GRIN lens. Alternatively, separate input and output GRIN lenses may be used. The amount of attenuation can be indicated by a potentiometer.