JPS6015610A - Multiple-cored optical cable coupler - Google Patents

Abstract

PURPOSE:To enable parallel transmission and reception of many pieces of parallel data and transmission of the data at a higher speed by providing light emitting elements and photodetectors to both ends of optical fiber cords which are used with a large number in parallel. CONSTITUTION:An optical connector is made into a slender and long rectangular parallelepiped shape which is provided internally with many spaces for housing photoelectric transducers. 2 is a photoelectric transducer which is a light emitting element, photodetector or a combination thereof. Many pieces of optical fiber cores 4 are attached to the opposite side of connecting pins 3 and the end faces thereof face the photoelectric transducers. Each core 4 is constituted of a sheath 5 of soft PVC, etc., a longitudinal fiber-like reinforcing material 6, an inside covering 7 of nylon, etc. and an optical fiber strand 8 consisting of a core and clad.

Description

Detailed Description of the Invention (7) Technical Field The present invention relates to an optical fiber cable coupler used in optical communications and optical data links.

Optical fiber has excellent features not found in conventional electronics, such as broadband, light weight, no induction, no crosstalk, high insulation, corrosion resistance, and no detonation.

For example, an optical digital link consists of three major components: an optical transmitter, an optical receiver, and an optical fiber.

The electrical signal provided as input to the optical transmitter is amplified and drives the light emitting diode. Light emitting diodes convert electrical signals into optical signals. The optical signal is launched into an optical fiber with suitable connectors at both ends. The optical signal propagates through an optical fiber and reaches an optical receiver. here is pi
There are n photodiodes that convert optical signals into electrical signals.

In the optical receiver, the electrical signal is amplified, passed through a binarization circuit including a comparator, binarized, and restored to a digital signal.

An optical analog link also consists of three major components: an optical transmitter, an optical receiver, and an optical fiber. The signals transmitted and received are analog signals, and the circuit configuration of the optical receiver is different.

If it is desired that transmission and reception occur bidirectionally, transmitters and receivers are provided for both. In this case, there are two optical fibers, one fiber transmitting the optical signal from A to B, and the other fiber transmitting the optical signal from B to A.

A light emitting diode (Lli:D) and a photodiode (PD') are housed in the cover in parallel, and the end of an optical fiber can be fitted in the immediate front of the cover.

(B) Conventional technology Optical fibers can be divided into three types: quartz fiber, multicomponent glass fiber, and plastic fiber.

Silica-based fiber has the characteristics of low loss, wide transmission band, and high reliability.

Plastic fiber has high loss but is low cost.
It has the characteristics of a large numerical aperture and easy handling.

FIG. 3 is a perspective view showing a simple configuration of a conventional optical fiber communication system.

An optical fiber C connects a transmitting side A and a receiving side B.

When the sending signal data SD is given to the sending side A, it is converted into E10 and transmitted through the optical fiber C. When the optical signal reaches the receiving side B, it is subjected to O/E conversion and is taken out as received signal data RD. In such a case, only one optical fiber C is sufficient.

In many cases, two-way communication is more convenient than one-way communication, so both A and B are equipped with a transmitter/receiver and communicated using two optical fibers.

The data to be sent and received may be digital data, analog data, etc. In some cases, digital data and analog data are mixed.

When there is a large amount of data to be sent, each data is sampled at a cycle smaller than the speed of temporal fluctuation of each data and converted into a time-series signal (parallel/
serial conversion).

On the receiving side, this data is serial/parallel converted and restored to the original data. The shorter the time-series signal unit, the more parallel data can be sent.

However, doing so requires a wide bandwidth, which is difficult to do using cheap fiber.

For short distances, such as optical data links within factories, inexpensive optical fibers are often used.

Multimode fibers with relatively large numerical apertures are used, even if they are plastic fibers that have a large numerical aperture and are resistant to bending, or quartz fibers. As for light emitting elements, light emitting diodes are easier to use than lasers.

In a system including stations A and B, a lot of parallel data may have to be transmitted.

Even if the number of data that can be transmitted is increased by parallel/serial conversion, there is a limit. In such a case, two optical fibers will not suffice, and four, six, etc. will be needed.

Since the unit of optical fiber is two, even in such a case, multiple optical fiber cables of two each must be strung separately between ASB stations.
Lli:D and PD groups were also provided separately.

Several types of optical fibers bundled in parallel are already known.

For example, there is an image fiber. This is made by bundling thousands to tens of thousands of optical fibers consisting of a core and cladding, heating and softening them, and pulling them from both sides to reduce the diameter. They are made in diameters ranging from several centimeters to less than one centimeter. In this case, each optical fiber becomes one pixel, and each pixel can transmit hue and brightness. The feature is that a single image can be broken down into pixels and directly transmitted as is.

However, image fibers cannot separate the signals transmitted by individual pixels;
It cannot be used for anything other than image transmission.

A bundle fiber is made by bundling a large number of optical fibers each consisting of a core and a cladding, and covering the entire fiber. Since the numerical aperture NA is large, the coupling efficiency with the LED is high. It is easy to assemble, and precise machining of the end face is not required.

However, bundle fibers also transmit one optical signal as a whole, and each optical fiber wire is not used as an independent signal transmission path.

(1) Purpose The present invention aims to transmit and receive a large amount of parallel data in parallel to enable higher-speed data transmission.

For this reason, the present invention uses one or more optical fiber cords in parallel, and has a light emitting element such as a light emitting diode or a laser diode, a pin photodiode, an avalanche photodiode, etc. at both ends of the many optical fibers. A light receiving element is provided.

The multi-core optical cable coupler of the present invention includes (1) a cable that integrates a large number of optical fiber cords, and (2) a cable that accommodates therein the same number of photoelectric conversion elements as the optical fiber cords, and has an end portion of the optical fiber cord. and two optical connectors that are fixed opposite to the photoelectric conversion element.

FIG. 1 is a perspective view showing only the vicinity of one end of the multi-core optical cable coupler of the present invention.

The optical connector 1 has an elongated rectangular parallelepiped shape, and has a large number of photoelectric conversion element housing spaces inside.

While conventional optical connectors accommodate only one or two photoelectric conversion elements, the present invention accommodates more. It is at least 4 or more. FIG. 1 shows an optical connector that accommodates eight photoelectric conversion elements 2. As shown in FIG.

Of the eight photoelectric conversion elements 2, four can be light emitting elements and one can be a light receiving element. In this way, four types of data can be transmitted and received independently at the same time.

It is also possible to use all eight light emitting elements or all eight light receiving elements, which corresponds to the case where one-way communication is sufficient instead of two-way communication.

In addition, the number of light emitting elements and light receiving elements may be selected arbitrarily depending on the purpose.

A connecting pin 3 protrudes rearward from the rear surface of the photoelectric conversion element 2. The connecting pins 3 can also be soldered directly to the electrical circuit board.

It is convenient to set the spacing between the connecting pins 3, .

Optical connector 1 on the opposite side from the side where connection pin 3 protrudes
Optical fiber cords 4, 4, .

The optical fiber cord 4 may be made of quartz, multi-component glass, or plastic.

This example shows a quartz glass-based optical fiber 2, and in order from the outside, an outer sheath A15 made of soft PVC, a vertical fiber reinforcing material 6 such as Kevlar (trade name), and an inner sheath 7 made of nylon or the like. , a core, and a fiber wire 8 consisting of a cladding are combined concentrically.

Adjacent optical fiber cords 4 transmit independent optical signals. This is because the outer covering 5, reinforcing material 6, inner covering 7, etc. are separated from each other. The optical fiber cords 4 that are adjacent to each other are adhered to each other at the outer sheath W5 and are continuous in a plane.

A large number of optical fiber cords 4, . . . can therefore be handled in the same way as a single cable. Since the entire cable is flat, it can be called a flat cable in the same way as an electrical cord. Installation makes work easier.

Only at the separation part W, the optical fiber cable 4,...
are separate, but most of the rest are integral to each other.

The optical fiber cord is made by peeling off the outer sheath 5, reinforcing material 6, inner sheath N7, etc. from the tip, gluing an appropriate plug (not shown), and inserting the plug into the hole in the front of the optical connector 1. Fix to connector 1.

The photoelectric conversion elements 2, . . . are used for charging conversion and conversion of the optical connector 1.
It is inserted into the element housing space, and the rear opening is covered with a cap 9.

Although FIG. 1 shows only one side of the optical cable coupler, the optical connector 1 containing the photoelectric conversion elements 2, . . . is similarly fixed to the other end of the optical fiber cord 4, 4, .

Of course, different types of photoelectric conversion elements are provided at both ends of one optical fiber 2/cord 4.

If there is a light emitting element at one end, there is a light receiving element at the other end.

In the end, the optical fiber cord 4 and the optical connectors 1.1 at both ends
are integrated, and constitute the multi-core optical cable coupler of the present invention.

The lateral length of the optical connector 1 and the number of optical fiber cords 4 are determined in advance depending on the purpose.
You can also decide the number and arrangement of...

Instead, the optical connector 1 can be made long enough in the lateral direction, and the number of optical fiber cords 4, . . . can be made sufficiently large. Depending on the specific purpose, the optical connector is cut (the cut surface H is shown with diagonal lines), and the optical fiber cord 4 is cut to form a multi-core optical cable coupler.

FIG. 2 is a plan view of one end of a multi-core optical cable coupler showing another example.

This allows for expansion. The side surface of the optical connector 1 is provided with an extension notch 10 and an extension projection 11 that can be fitted into the extension notch 10.

Optical fiber cord 4 with m optical fiber cables...
As long as it includes m photoelectric conversion elements, when two such optical cable couplers are combined, an optical cable coupler having 2m optical fiber cords and 2m photoelectric conversion elements can be obtained.

The combination is performed by fitting the extension protrusion 11 into the extension notch 10 of the adjacent optical connector 1.

(k) Effects Since there are a plurality of transmitters and receivers, or one or the other, parallel data can be transmitted as is without parallel/serial conversion. Therefore, parallel data can be transmitted at high speed.

Although many optical fiber cords are independent in terms of transmission signals, they are integrated as a whole, and a large number of photoelectric conversion elements are housed in a single optical connector, making installation, wiring, and erection work extremely difficult. It can be done conveniently.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing one end of a multi-core optical cable coupler of the present invention. FIG. 2 is a plan view showing only one end portion of another example of the multi-core optical cable coupler of the present invention. FIG. 3 is a perspective view of the configuration of a conventional optical fiber communication system. 1 ・・・ ・・・ ・・・ Optical connector 2
...... Photoelectric conversion element 3 ......
... Connection bin 4 ...... Optical fiber cord 5 ...... Outer sheathing 6 ...... Reinforcement material 7 ......・・・・・・ Inner coating 8 ・・・・・・・・・ De-iva wire 9 ・・・・
・・・・・・ Cap 10 ・・・・・・・・・
・Expansion notch 11・・・・・・Expansion protrusion Inventor: Hiroshi Kumamoto

Claims (1)

[Claims] A cable in which a large number of optical fiber hoods 4.4, . . . are integrated by a jacket tube 5 and an optical fiber hood 4.4
The same number of photoelectric conversion elements 2.2, . . . are housed inside, and the ends of the optical fiber cords 4.4, . A multi-core optical cable coupler characterized by JR consisting of two optical connectors 1.1 fixed facing each other.