Abstract: A vehicle network system is provided with a plurality of star networks, a plurality of devices mounted on a vehicle are connected in a star shape through respective branch lines in each of the star networks, and a trunk line for connecting the plurality of star networks, the branch lines are communication lines for optical communications, and the trunk line is a communication line for electric communication.

Abstract: A vehicle network system is provided with a plurality of star networks, a plurality of devices mounted on a vehicle are connected in a star shape through respective branch lines in each of the star networks, and a trunk line for connecting the plurality of star networks, the branch lines are communication lines for optical communications, and the trunk line is a communication line for electric communication.

Abstract: Respective stoppers are engaged with a jacket at positions along a longitudinal direction of an optical cable different from each other by using a plurality of the stoppers having pairs of engaging pieces arranged in parallel with each other by an interval dimension smaller than a width dimension of the jacket of the optical cable. Further, positions of engaging the pairs of engaging pieces and the jacket may be shifted from each other by a quarter periphery in a peripheral direction of the optical cable for the respective stoppers.

Abstract: An electric connector portion, an optical element and a mounting board formed with a circuit executing a predetermined signal conversion and relay processing are held by a case. The case includes an optical element-containing recessed portion having electrical conductivity, and the optical element is arranged in the optical element-containing recessed portion. Further, the case may include a mounting part-containing recessed portion independently from the optical element-containing recessed portion, and mounting parts on the mounting board may be arranged in the mounting part-containing recessed portion.

Abstract: An optical cable stopper includes a plurality of cut-in portions that cut side portions of a cover portion of an optical cable, a plurality of side guide portions that guide the cut-in portions by being brought into sliding contact with the side portions of the cover portion such that the cut-in portions do not cut respective fiber core lines when cutting the side portions of the cover portion, and a center guide portion that guides the cut-in portions by being guided to insert into a guide groove provided in the cover portion such that the cut-in portions do not cut the respective fiber core lines when cutting the side portions of the cover portion.

Abstract: Respective stoppers are engaged with a jacket at positions along a longitudinal direction of an optical cable different from each other by using a plurality of the stoppers having pairs of engaging pieces arranged in parallel with each other by an interval dimension smaller than a width dimension of the jacket of the optical cable. Further, positions of engaging the pairs of engaging pieces and the jacket may be shifted from each other by a quarter periphery in a peripheral direction of the optical cable for the respective stoppers.

Abstract: An electric connector portion, an optical element and a mounting board formed with a circuit executing a predetermined signal conversion and relay processing are held by a case. The case includes an optical element-containing recessed portion having electrical conductivity, and the optical element is arranged in the optical element-containing recessed portion. Further, the case may include a mounting part-containing recessed portion independently from the optical element-containing recessed portion, and mounting parts on the mounting board may be arranged in the mounting part-containing recessed portion.

Abstract: An optical connector electrically connects a surface-implemented type optical element held at a position separated by a predetermined distance from a wiring substrate and a wiring pattern of the wiring substrate. A surface-implemented type optical element is held at a height position apart from the bottom of the connector housing by a predetermined distance within an element-storing depression of the connector housing. The back of the element-storing depression has an opening that is closed by a lid portion. A lead frame is provided in the lid portion. A connecting portion on one end of the lead frame is in contact with an electrode portion of the optical element within the element-storing depression. A soldering portion on an other end of the lead frame is exposed to the outside of the connector housing to be soldered to a wiring pattern of a wiring substrate. A lock-associating portion with a lock piece is integrally provided on the bottom surface side of the connector housing.

Abstract: A first housing for storing and holding a surface-implemented type optical element and a second housing to which an optical connector of the other party fits and connects are provided separately. In the first housing, a fixing pin to be soldered to a wiring substrate is vertically provided, and a guide sleeve portion for guiding an optical fiber toward the optical element projects. The position mounting the first housing can be freely adjusted in a range that the fixing pin can be movably inserted to a through-hole of the wiring substrate and can move inside. The second housing has a lock portion for maintaining the connection state with the optical connector of the other party.

Abstract: A light-relay element is interposed between a light-emitting end face of a plastic optical fiber and a light-receiving face of a light receptor such as a photo-diode unit. The light-relay is in the form of a fiber and has a graded index. The light-relay element contains a core portion, the diameter of which decreases gradually from the end adjacent the fiber to the end adjacent the photo-diode unit. This configuration enables minimization of the connection loss between the fiber and the light receptor.

Abstract: A fiber optic cable has a light-exiting face. A cable-adapter is affixed to the light-exiting face. The cable-adapter has a cylindrical outer surface, a diameter of which is gradually tapered down. Light leaving the face of the cable is moved towards an optical receptor and gradually converged, by virtue of the tapered cylindrical surface, of the cable-adapter and emitted. In this manner, an optical loss is minimized. To prevent a leak through the tapered surface, the tapered surface is coated with a low refractive index film. Further, a ferrule is used to position the cable-adapter relative to the fiber optic cable. By virtue of this configuration, an optical leakage can be minimized when the light is received by an optical receptor having a small surface chip.

Abstract: A structure for connecting a plastic optical fiber to a light receiving element. The plastic optical fiber has an end face that emits light. The light receiving element has a light receiving face that has a smaller surface than that of the end face of the plastic optical fiber. The structure includes a conical outer surface, a fiber-side surface, and an element-side face. The diameter of the structure decreases gradually from the fiber-side face towards the element-side face. The structure is adapted for interconnecting the end face of the plastic optical fiber and the light receiving face of the light receiving element where the connection loss therebetween is minimized.

Abstract: A plastic optical fiber is provided with a desired length and with a desired graded refractive index. To this end, a base polymer is first mixed with a non-polymerizable compound having a higher refractive index to obtain a fiber material. This material is then melted and continually spun into a fiber. The fiber is dipped into a polymerizable monomer and heated, during which both the non-polymerizable monomer and the polymerizable monomer diffuse inside the fiber, thereby grading the refractive index. When the fiber is heated, the diffused polymerizable monomer is polymerized and the fiber is hardened. The fiber is further coated with a cladding to form the desired plastic optical fiber. Various devices are provided for carrying out the above described processes.

Abstract: A light branching and coupling device excellent both in transmitting performance and in distributing performance in which the intermediate portion of an optical fiber 10a (10b) is thermally drawn to form light transmission fiber portions 11a and 15a (11b and 15b) and a light branching and coupling fiber portion 13a (13b) having a diameter smaller than that of the light transmission fiber portions and, at the same time, form tapering fiber portions 12a and 14a (12b and 14b) between the light transmission fiber portions and the light branching and coupling fiber portion so that the tapering fiber portions are tapered off gradually toward the light branching and coupling fiber portion 13a (13b) side. The light branching and coupling fiber portions 13a and 13b thus formed are fused with each other.

Abstract: The terminal treatment device for a plastic optical fiber is improved so that void formation between the melt zone of the ferrule and the plastic optical fiber is avoided, leading to the prevention of crack formation. The device constitutes a chamber, the upper side of which is open, a heater in the chamber, a heated element which may be at the top of the chamber, and a base frame and a top frame to secure the heated element to the chamber. The element is a rectangular plate, made of a metal having good thermal conductivity and includes a thicker part and a thinner part surrounding it. At the center of the thicker part, there is provided a blind hole into which the tip of the ferrule is fitted. A plurality of heat evacuation vents is formed around this blind hole and elsewhere in the chamber to facilitate cooling.

Abstract: A light branching and coupling device excellent both in transmitting performance and in distributing performance in which the intermediate portion of an optical fiber 10a (10b) is thermally drawn to form light transmission fiber portions 11a and 15a (11b and 15b) and a light branching and coupling fiber portion 13a (13b) having a diameter smaller than that of the light transmission fiber portions and, at the same time, form tapering fiber portions 12a and 14a (12b and 14b) between the light transmission fiber portions and the light branching and coupling fiber portion so that the tapering fiber portions are tapered off gradually toward the light branching and coupling fiber portion 13a (13b) side. The light branching and coupling fiber portions 13a and 13b thus formed are fused with each other.

Abstract: The optical fiber connector assembly including a clamping member, a holding member, and a connector housing provided with a ferrule and a receiving chamber. The optical fiber to be connected has a coated portion and an exposed end. The clamping member is crimped on the coated portion of the fiber and the fiber is inserted into--and held by--the holding member, thus constituting a fixing device. This device, together with the optical fiber, is inserted into the chamber of the connector housing through the opening in its rear, so that the exposed end of the fiber is secured in the ferrule. The clamping member desirably comprises a cylindrical portion fixed to the coated optical fiber, and a flange, by which the clamping member is fixed to the holding member. The holding member can be formed by a pair of elements. One face of each element is configured so that, when the two elements are in opposing abutment, they cover and retain the clamping member and the coated fiber.

Abstract: A system of detecting an occurrence of a trouble in an optical communication line having a plurality of nodes with a sending port and a receiving port, a plurality of 2-input & 2-output couplers and fibers connecting the nodes and the couplers for distributing any signal issued from a node to all the nodes. The coupler has an intersecting allocation between two inputs and two outputs. The intersection in the coupler makes the recurring signal pass only through a series of evanescent linkages of the couplers to the receiving port of the same node. When a trouble arises, the evanescent linkage is more likely to be broken down than the direct linkage and the node notices the trouble by the extinction of the recurring signal.

Abstract: An active optical coupler for use in an optical data link communication system includes a multi channel coupler having a plurality of input channel fibers for receiving an original optical signal, an optical branch separating the original optical signal into a predetermined number of separated optical signals, and a plurality of output channel fibers for distributing the separated optical signals. An amplification circuit is connected to one of the output channel fibers which distributes the separated optical signal having a lowest power for amplifying this separated optical signal to produce an amplified optical signal. This amplified optical signal is supplied to any other of the input channels other than that which the original optical signal is input to and then distributed to the output channels again.

Abstract: The present invention is directed to an optical coupler, only formed by a plurality of all plastic fibers, and a method of producing the same. Two all plastic fibers each of which has a core are placed in contact with each other over a predetermined length. Ultrasonic vibration is applied to a contacting portion of the all plastic fibers so as to bond the cores with each other at the contacting portion. Thus, the optical coupler with a low-excess-loss can easily be produced.