Abstract: An optical fiber multiplexing/demultiplexing devices for the multiple-fiber ribbon of optical fibers, and the fabrication method.

Abstract: An optical multiplexing/demultiplexing device consisting of one or more units, each of which consists of one or more components constituting 2.times.2 circuits, each of which consists of a pair of substrates having a pair of V-grooves arranged to mate with each other and a pair of optical fibers which are installed in the pair of V-grooves connecting through a single unit one. One optical fiber is thereby directly connected through a single unit to a plurality of components arranged in series in the single unit to constitute a tree structure for multiplexing.

Abstract: A variable light attenuator of optical connector type. It consists of an alignment adapter, first ferrule fastening means, and second ferrule fastening means. The alignment adapter provides an alignment through hole concentrically passing therethrough along the optical axis thereof. First ferrule fastening means fastens first ferrule whose edge is exposed to an intermediate air gap and is 7 degrees or more inclined to a plane perpendicular to the optical axis, passes the first ferrule through the alignment through hole, and fastens the first ferrule to the alignment adapter. Second ferrule fastening means fastens second ferrule which is almost the same as first ferrule fastening means in both structure and functions, but movable along the optical axis to appropriately set the gap between the first and second ferrules while the edges of the first and second ferrules are kept in parallel by key pin and key groove to specify the designated attenuation.

Abstract: An optical multiplexer of the variable coupling type for branching an input signal from a first optical fiber to a second fiber at a given ratio. The optical multiplexer is made of a pair of substrates, each having a side defining a reference plane and a face perpendicular to the reference plane. The respective perpendicular faces each have a V-groove disposed at an angle greater than zero and less than 5.degree. to the reference plane. The first and second optical fibers are positioned in the respective V-grooves. Each of the faces of the substrates with the optical fibers in the V-grooves are abraded until the cores of the optical fibers are just exposed. The substrates are assembled to contact each other at the respective faces such that the exposed cores of the optical fibers face each other and are separated by a distance defining the ratio of branching of the input signal.

Abstract: An optical multiplexing/demultiplexing device with multiple ports. A plurality of pairs of V-grooves are provided in parallel on each substrate made of invar or the same type of material as the optical fibers with the same linear expansion coefficient so as to store the optical fibers. A pair of substrates having the symmetrical structure are assembled to form a plurality of optical multiplexing/demultiplexing circuits. A pair of trenches are provided on each substrate in parallel with and on both sides of the V-grooves. Optical fiber terminals led from the respective V-grooves are connected to form a 1.times.n (n: an integer.gtoreq.2) star coupler structure.

Abstract: An optical fiber end-surface polishing device has a polishing disc assembly which makes a polishing disc turn on its own axis and revolve around some other axis with respect to a base supporting a polishing member. There is an optical fiber holder assembly supporting an optical fiber holder section for holding a plurality of optical fibers. The optical fiber holder assembly abuts the end surfaces of the optical fibers against the polishing member while being biased in a direction perpendicular to the polishing member.

Abstract: An optical fiber connecting device in which a pair of ferrules holding optical fibers in their central holes and opposing at their end faces are inserted in a through bore of an aligning sleeve having a structure that enables the angles of the ferrules' end faces at which they contact each other to be adjusted by rotating both or either of the ferrules, and enables the adjusted positions to be fixed. A pair of optical connector plug assemblies each include a ferrule having an optical fiber-holding central hole and a threaded portion formed at one end of its outer-diameter portion, a cylindrical position-determining ring having a threaded hole rotatably engageable with the threaded portion and a position-determining key provided on its outer-diameter portion, and a ferrule-urging compression coil spring and a threaded-hole-provided engagement nut which are slidably fitted around the outer-diameter portion of the ferrule.

Abstract: An apparatus for polishing end faces of optical fibers so that they are each given a convex spherical surface. The optical fibers are mounted on a jig so that their end faces are pressed against a polishing film attached to a rotary disk. The polishing film is made of a flexible (or cushionable) soft material having a Shore hardness of 10 through 100, such as synthetic rubber. The jig performs an orbital motion without rotation on its own axis.

Abstract: An optical fiber connector according to the present invention is of the type in which optical fibers are inserted into a pair of ferrules which in turn are forcibly inserted into a sleeve so that the end surfaces of the optical fibers are in contact. The fiber misalignment, or disagreement of the centers of the optical fiber cores, may be corrected by relating a ferrule supporting plug while the ferrules are disposed in a sleeve adapter which holds the sleeve.

Abstract: A metal mold for resin molding of the type which comprises the combination of a fixed side metal mold assembly and a movable side metal mold assembly. Melt resin material is supplied into and filled in a cavity formed between the fixed side metal mold assembly and the movable side metal mold assembly, and pressure applied to obtain a desired mold thickness of a disk, etc. The metal mold for resin molding according to this invention further includes a spacer inserted between the ends of the guide post rods and the movable side metal mold assembly, to define a gap for adjusting the metal mold thickness.