JPH01222531A - Optical branching device - Google Patents

Abstract

PURPOSE:To eliminate the need for a mechanical drive device, to improve the reliability, to miniaturize and to reduce the cost by reflecting an optical signal radiated from a light emitting element in a half mirror, and sending it to a radiation side waveguide path. CONSTITUTION:An optical signal radiated from an incident waveguide path 2 is subject to photoelectric conversion by a transmission light emitting element 1, part of its is transmitted as it is, and sent to a radiation side waveguide path 3. The output signal subject to photoelectric conversion is amplified by an amplifier means 4 and sent to light emitting element 7, which stimulates a signal to a half mirror 1M adhered to the rear face of the transmission light emitting element 1 and the optical signal is sent to the radiation side waveguide 3 while being reflected in the half mirror 1M. Thus, no mechanical driver is required, the reliability is improved, the size is made small and low cost is attained.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an optical signal branching device in a leading waveguide.

[Conventional technology]

FIGS. 5 and 6 show, for example, a conventional optical branching device disclosed in Japanese Patent Application Laid-Open No. 62-73225 entitled "Optical Switch".

FIG. 5(a) shows a branching device of an optical switch, in which a transmission prism 51 outputs light from an upper optical input end 52 to a lower optical output end 53, which connects, for example, the 8th station 61 in FIG. The light is transmitted through the lower optical input end 54, through the prism 51, through the upper optical output end 55, and to the optical switch 63.

In this way, the optical signal from the A station 64 is transmitted to the 0 station 66 through the optical fiber 65.

During normal operation, each of the stations B, C, and D amplifies the optical signal to compensate for attenuation in the optical path. If a failure occurs in one of these stations, the prism 51 is removed from the optical path above the optical switch 63, as shown in FIG. 5(b), and the light is routed to the next station without being split or amplified. configured to transmit.

[Problem to be solved by the invention]

Conventional optical switches (optical branching devices) are configured as described above, so it is necessary to use optical transmission prisms that are expensive and difficult to mass-produce for optical branching, and the optical amplification section of each communication station is In the event of a failure, a drive mechanism is required to mechanically remove the transmitting prism 51 from the main optical path as shown in FIG. 5(b), resulting in a problem that the device becomes expensive and large.

This invention was made to solve the above-mentioned problems, and aims to provide a highly reliable, compact, and inexpensive optical branching device that does not require a mechanical drive mechanism.

[Means to solve the problem]

The optical branching device of the present invention photoelectrically converts the optical signal from the input side waveguide between the input side and output side waveguides, and transmits a part of the optical signal to the output side waveguide. A transmission type photoelectric element is arranged to be inclined at a certain angle with respect to each of the waveguides, and an amplification means for amplifying the output signal of the transmission type photoelectric element, and an amplification means for amplifying the output signal of the transmission type photoelectric element, and an amplification means for emitting light based on the output from the amplification means to emit light to transmit the light to the transmission type. A light emitting element that emits an optical signal to the light emitting element, and a half mirror attached to the back surface of the transmissive photoelectric element opposite to the output waveguide side, the light emitting element emits an optical signal to the light emitting element. is bent by this half mirror and sent to the output side waveguide.

[Effect]

The transmission type photoelectric element photoelectrically converts the optical signal emitted from the input side waveguide, and transmits a part of the signal as it is to the output side waveguide. The photoelectrically converted output signal is amplified by an amplifying means and sent to a light emitting element, and this light emitting element emits an optical signal to a half mirror attached to the back side of the transmissive photoelectric element. It is bent at - and sent to the output waveguide.

[Embodiments of the invention]

Hereinafter, one embodiment of the present invention will be described in FIGS. 1 to 4(a),
The explanation will be based on (b).

In each figure, 1 is a porous photoelectric element as a transmission type photoelectric element, and this optical fiber 2 is connected between an input photometric fiber 2 as a waveguide and an output side optical fiber 3
．． 3, at a constant angle, that is, at an angle of 45 degrees. In this porous photoelectric element 1, as shown in FIG. 4(a),
As shown in (b), a transparent electrode 10a is provided on the substrate, and a back electrode 10b is provided on the back surface via a PN layer, and a part of the optical signal emitted from the input optical fiber 2 is transmitted. Innumerable transmission holes 10s are formed. Porous photoelectric element 1 facing the output side optical fiber 3 side
A half mirror IM is attached to the back electrode 10b. This porous photoelectric element 1 includes an electronic amplifier circuit 4. Constant voltage power supply 5. It is connected to the output transistor and is configured to convert the received optical signal into an electrical signal, amplify this electrical signal with the electronic amplifier circuit 4, and send it out from the output transistor as a digital pulse output P. has been done. 7 is a light emitting element whose cathode side is connected to the digital pulse output side via a current control resistor 8, and the constant voltage power supply 5 is shared in anode measurement. Porous photoelectric element with the above half mirror IM attached 1. Electronic amplifier circuit 4. The output transistor, the light emitting element 7, and the like constitute the optical branching device 9 of the present invention. As shown in FIG. 2, this optical branching device 9 is connected to each station B and C.

It is installed at station D. Reference numeral 11 denotes a microcomputer provided in each station, to which the digital pulse output P is inputted via a buffer 12. 13 is a driver (drive circuit using an external signal).

Next, the operation of the optical branching device 9 will be explained.

The electrical signal photoelectrically converted by the porous photoelectric element 1 is amplified by the electronic amplifier circuit 4 and output to the light emitting element 7, and the light emitting element 7 emits an optical signal based on this output. Then, this optical signal is reflected by the half mirror IM and output to the output side optical fiber 3. Here, there is a concern about a phase shift between the transmitted light signal transmitted through the transmission hole 10s of the porous photoelectric element 1 and the amplified optical signal emitted from the light emitting element 7 and reflected by the half mirror IM. For example, it was found that there is no problem with low-speed signal transmission such as 9600 bps even when the response delay is lvs.

Furthermore, the operation when the optical fibers 2.3 between the stations A, B, C, and D are connected by the optical branching device 9 will be explained based on FIG.

The optical signal transmitted from the A station passes through the optical fiber 2 and reaches the optical branching device 9 of the B station. As described above, within this optical branching device 9, an optical signal is received by the porous photoelectric element 1, and the signal is self-amplified and outputted to the output side optical fiber 3, so that the signal is sufficiently transmitted in the direction of the optical branching device 9 of the 0 station. Powerfully transmits high-quality optical signals. In addition, at the B station, the digital pulse output P of the output range transistor passes through the buffer 12,
The microcomputer 13 decodes the RD large input signal.

Furthermore, if the local station needs to transmit to another station, it pulse-drives the driver 13 from the digital pulse output P and sends the signal to the free time of the optical fiber 2.3, causing the light-emitting element 7 to emit pulses. and can send and communicate. Here too,
Even if the electrical function of the optical branching device 9 of the B station and the 'B station breaks down, for example, if a faulty connection of the power supply Vcc 2 or parts such as the light emitting element 7 fails, the transmission signal from the A station will be transferred to the optical branch of the B station. The signal passes through the device 9 and reaches station 0, and if station 0 is alive, it can be transmitted one after another in the direction after the next station D.

In addition, in order to further reduce the size of the optical branching device 9 of the present invention,
As shown in FIG. 3, a porous photoelectric element 1°, an electronic amplification circuit 4. By integrating the output transistor into the light receiving IC 14, an ultra-small optical branching device 9 can be obtained. Further, the ratio of the output light signal emitted from the optical fiber 2 to the porous photoelectric element 1 and the transmitted light signal transmitted through the transmission hole 10s can be freely selected depending on the number of the transmission hole 10s, and The optimal ratio of received light and transmitted light signals can be set depending on the type of light and transmission distance.

〔Effect of the invention〕

As explained above, according to the optical branching device 9 of the present invention,
A transmission type photoelectric element is provided between the waveguides on the input side and the output side, which photoelectrically converts the optical signal from the input side waveguide, and transmits a part of the optical signal to the output side waveguide. an amplifying means arranged at a certain angle with respect to the waveguide and amplifying the output signal of the transmissive photoelectric element; and an amplifying means for amplifying the output signal of the transmissive photoelectric element, and emitting light based on the output from the amplifying means to transmit an optical signal to the transmissive photoelectric element. a light emitting element that emits light, and a half mirror affixed to the back side opposite to the output waveguide side of the transmission type photoelectric element, and the optical signal emitted from the light emitting element is bent by the half mirror. Since the optical signal is sent to the output waveguide, even in the event of an electrical function failure, the optical signal can be transmitted to the next station without using a mechanical drive mechanism, creating a highly reliable, compact and inexpensive optical branch. can get the equipment

[Brief explanation of the drawing]

1 and 4(a) and 4(b) show an embodiment of the optical branching device of the present invention, FIG. 1 is an internal configuration diagram, and FIG. 6 is an operational diagram. l...Porous photoelectric element (transmission type photoelectric element), 2゜3.
...Optical fiber (waveguide), 4...Electronic amplification circuit (
amplifying means), 7... light emitting element, 9... optical branching device. Agent Masuo Oiwa (2 people) 2nd □□□ 0th station 0th station B Martyred Pigeon 3 L-＋＋＋＋＋
++ -"Figure 6 61 1)21)t)

Claims (1)

[Claims] A transmission type photoelectric element is provided between the waveguides on the input side and the output side, which photoelectrically converts the optical signal from the input side waveguide, and transmits a part of the optical signal to the output side waveguide. an amplifying means arranged at a certain angle with respect to the waveguide and amplifying the output signal of the transmissive photoelectric element; and an amplifying means for amplifying the output signal of the transmissive photoelectric element, and emitting light based on the output from the amplifying means to transmit an optical signal to the transmissive photoelectric element. a light emitting element that emits light, and a half mirror affixed to the back side of the transmissive photoelectric element opposite to the output waveguide side, and the optical signal emitted from the light emitting element is bent by the half mirror. An optical branching device characterized in that the light is transmitted to an output side waveguide.