JPH0223733A - Optical communication equipment - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an optical communication device, and in particular, to an optical communication device capable of bidirectionally transmitting and receiving optical signals using a single optical fiber. be.

[Prior Art] FIG. 5 shows, for example, the technique of "
This is a branching communication device of the conventional optical communication device shown in ``Optical Switch.'' Figure 5 (a) shows the state in which the transmission prism is placed in the optical path, and Figure 5 (b) shows the state in which the transmission prism is removed from the optical path. FIG. 6 is a block diagram showing a conventional optical transmission system. Hereinafter, a "communication node" refers to a communication device or a communication device layer, and is also simply referred to as a station.

In Figure 5, (1) is an optical switch that switches the optical path, which is the traveling direction of the optical signal, and (2) is an optical transmitter with excellent light transmission that is movably installed in the optical switch (1). It's a prism. This transmission prism (2) is disposed in the optical path so that an optical signal can pass through the station in the event that one of the plurality of stations fails.

(3) and (4) are the upstream and downstream optical input ends of the optical switch (1), (5) and (6) are the optical switch (1)
They are the downstream optical output end and the upstream optical output end of the.

In FIG. 6, (7) to (10) are each a communication device (
station), (7) is station B, (8) is station C, and (9) is station D.
Station (10) is station A. (11) is an optical fiber that transmits optical signals.

A conventional optical communication device is configured as described above, and uses an optical switch (1) using a transmission prism (2) as a branch communication device of the optical communication device. This operation will be explained below.

Light entering the upstream light input end (3) of the optical switch (1) passes through the transmission prism (2) and exits from the downstream light output end (5) (see FIG. 5(a)). For example, this light passes through the B station (7) in FIG. 6) to the optical switch (1> of the next station, C station (8).
) is transmitted through the optical fiber (11) and sequentially through each station to D station (9).In normal conditions, the optical signal is transmitted to D station (9), B station (7), C station (8), and D station (9). At each station, the optical signal is amplified to compensate for attenuation due to light absorption, scattering, etc. in the optical path.

If a failure occurs in any of these stations, move the transmission prism (2) in the optical switch (1) for that station using a drive device (not shown). The light entering the upstream light input end (3) of the optical switch (1) is directly output from the upstream end (6) (Fig. 5(b)).
reference). Then, at the failed station, the light was transmitted to the next normal station without being branched or amplified.

In this way, in the conventional device, A station (10) → B station (7)
→ Station C (8) 90 stations (9) → Station A (10), forming a loop in which optical signals were transmitted in one direction.

[Problems to be Solved by the Invention] In the conventional optical communication device as described above, when a plurality of stations are connected to form one optical transmission system, when one of the stations fails, an optical switch ( 1), optical signals were transmitted to the phosphor layer by passing through the relevant station.

However, in conventional devices, an optical transmission prism (2) that is expensive and difficult to mass-produce is used in an optical switch (1) that is a branch communication device of an optical communication device.

Furthermore, when forming an optical transmission system, it is necessary to connect each station to form a unidirectional loop, which requires directionality in the transmission direction of the optical signal.

Furthermore, a drive mechanism is required to move the transmission prism (2) in the event of a failure in one of the stations, making the device itself expensive and large.

For this reason, the challenge for this type of optical communication device is to create an optical communication device that can perform optical branch communication that can simply transmit and receive optical signals in both directions without using expensive optical transmission prisms. It became.

Therefore, this invention was made to achieve the above-mentioned problems, and it is possible to perform optical communication in both directions, and even if one of the stations breaks down, the phosphor can be passed through the station. The object of the present invention is to obtain an optical communication device capable of transmitting optical signals through layers.

"Means for Solving the Problems" An optical communication device according to the present invention includes both connecting portions <22> that connect to an optical fiber (11) for optical communication.

(23) is branched into three systems, and one of the three systems is a light guide path (19) for passing light that allows optical signals from both directions to pass between the two connecting parts (22>, (23)); The other one is the both connection portions (22>).

(23) a received light guide path (20) having a first light receiving port (20a) and a second light receiving port (20b) for receiving optical signals from each direction; (2
2), a light guide path for transmitting light (21> having a first light transmitting port (21a>) and a second light transmitting port (21b>) for respectively transmitting optical signals in the direction of (23>); Light guide path for light (
20), the first light receiving port (20a) and the second light receiving port (20)
a light-receiving element (13) that receives an optical signal from the light-receiving element (13) and converts it into an electrical signal; an amplifier circuit (14) that amplifies the electrical signal from the light-receiving element (13); A light emitting element (1) that emits an optical signal is provided at the first light transmitting port (21a> and the second light transmitting port (21b)) of the light guide path (21).
7).

[Function] In the optical communication device of the present invention, there is provided a light guide path for passing light through which optical signals can pass from both directions between the connecting portions (22) and (23) connected to the optical fiber (11) for optical communication. (1
9) and both connecting parts (22>).

A received light light guide (20) having a first light receiving port (20a) and a second light receiving port (20b) each receiving an optical signal from the (23> direction), and both connecting portions (22>, (23) A light guide path for transmitted light (21) having a first light transmission port (21a) and a second destination port (21b), each of which transmits an optical signal in the > direction.
The optical signals from the first light receiving port (20a) and the second light receiving port (20b) of the received light light guide path (20) are transferred to the light receiving element (13) in the photoelectric conversion unit (B). ), the electrical signal is amplified by the amplifier circuit (14>), the light emitting element (17) converts the electrical signal into an optical signal, and the light guide path for transmitting light (21>) converts the electrical signal into an optical signal. Light mouth (21
a) and the second light transmitting port (21b), it is possible to receive the optical signal transmitted in the single-wire optical fiber (11) in both directions, and photoelectrically convert the optical signal into an electrical signal. . Then, various electrical signals can be photoelectrically converted and transmitted bidirectionally as optical signals. Moreover,
A part of the optical signal can directly pass through the light guide path (19) for transmitted light and be transmitted to the phosphor layer or the like.

[Embodiment] Fig. 1 is a circuit diagram showing a communication node of an optical communication device which is an embodiment of the present invention, and Fig. 2 is a cross-sectional view showing the vicinity of the connection part of the branch light guide path section of the communication node of Fig. 1. It is.

In the figure, (11) is an optical fiber that transmits a conventional optical signal (12) is a communication node which is the communication device of this embodiment. This communication node (12) consists of a branch light guide section (A>) and a photoelectric conversion section (B). (13
) is a light receiving element such as a photodiode that converts an optical signal into an electrical signal, (14> is an amplifier circuit that amplifies the electrical signal photoelectrically converted by the light receiving element (13), (15) is a constant voltage power supply, (16) is an output transistor operated by a signal from the amplifier circuit (14). (17) is a light emitting diode (LE) that photoelectrically converts various electrical signals into optical signals.
A light emitting element such as D), (1B) is a resistor that limits the current to the light emitting element (17).

The operation of photoelectrically converting and amplifying the above optical signal into an electric signal,
The photoelectric conversion unit (B) of the communication node (12) performs both the operation of photoelectrically converting an electrical signal into an optical signal. (19)
is a light guide path for passing light that allows optical signals to pass in both directions,
It serves as a bypass for optical signals. Reference numeral 20 denotes one received light guide path for receiving optical signals from both directions, and has a first light receiving port (20'a) and a second light receiving port (20b).

(21) is a light guide path for transmitting light that transmits optical signals in both directions, and includes a first light transmitting port (21a) and a second light transmitting port (21a).
21b). The above-mentioned light guide path for passing light (19), light guide path for receiving light (20), and light guide path for transmitting light (21) constitute a branch light guide section (A) of the communication notebook (12). (22) and (23) are connection parts between the optical fiber (11) and the branch light guide section (A). This optical fiber (
11> and the branching light guide (△) are as shown in Figure 2, and these connecting parts are connected to the light guide for passing light (19), the light guide for receiving light (20), and the light guide for transmitting light. It is in a three-branched state with the light guide path (21).

The optical communication device of this embodiment is configured as described above, and is connected to each communication node station (not shown) located on both the left and right side by an optical fiber (11) consisting of a single wire.

Here, the communication node (1
The operation 2) will be explained below.

For example, a case will be described in which an optical signal is transmitted from a station located on the left side in FIG. A part of the optical signal transmitted through the optical fiber (11) passes through the light guide path (19) for passing light, and is transmitted as it is to the station located on the right side via the optical fiber (11) on the opposite side. . A part of the light guide path (20) for received light passes through the first light receiving port (20a>
The light is transmitted from the light receiving element (13) to the light receiving element (13). The light receiving element (13) photoelectrically converts the signal into an electric signal, which is amplified by the amplifier circuit (14) and output driver transistor (1
6) Received signal input terminal R as collector output via
Communicate to D.

On the other hand, in the case of light transmission and transmission, the light emitting element (17) emits light in response to an electrical signal from the transmission signal output terminal TD. The optical signal photoelectrically converted by the light emitting element (17) is transmitted from the first light transmitting port (21a> and the second light transmitting port (21b) of the transmitting light guide path (21) to both the connecting portions (22>). , (23>) and are sent to the left and right optical fibers (11), respectively.
The signal is transmitted to the neighboring stations on both the left and right sides.

In the above case, the case where an optical signal is transmitted from the station located on the left side is described, but the same operation is performed when the optical signal is transmitted from the station located on the opposite side.

In this way, the optical communication device of this embodiment can receive optical signals from both left and right directions, and can also transmit optical signals from both directions.

Therefore, in this embodiment, there is no need to form a loop for optical communication even in optical fiber communication consisting of a single wire, and bidirectional optical communication is possible, making multi-drop bus communication possible.

Moreover, a part of the optical signal is passed through the light guide path (19
) (bus-through) and can be transmitted to the station located on the opposite side, so even if the station in question breaks down or the power goes out, the optical signal can be transmitted to the adjacent station. can be transmitted.

Therefore, even if one of the stations fails, the optical signal can be passed through that station and reliably transmitted to the phosphor layer.

Therefore, even if a communication system is configured with a large number of communication nodes (12), and even if this passing light can only pass through one station due to optical loss, three consecutive rounds As long as there is no failure, the entire communication system can be controlled. In particular, the probability that two consecutive stations will fail at the same time is theoretically extremely low compared to the probability that only one station will fail. Therefore, by employing the optical communication device of this embodiment, the reliability of the communication system can be dramatically improved.

Furthermore, since the optical communication device of this embodiment is capable of bidirectional communication, it is possible to use the same communication protocol as, for example, conventional electrical signal multi-drop bus communication using electrical coaxial cables.

That is, by attaching the communication node (12) to each station of an electric signal communication system such as a coaxial cable system,
Bidirectional optical communication can be easily performed.

Furthermore, in this embodiment, each operation such as branching of the optical signal, signal extraction, and light transmission as described above can be performed by the branching light guide section (A>) without using the expensive transmission prism (2). Since this branching light guide path section (A) can be formed of an optical fiber or the like, it becomes a very inexpensive device and miniaturization can also be promoted.

Next, an example of use of the communication system using the optical communication device of this embodiment will be explained. FIG. 3 is a circuit diagram showing a control system for an air conditioner which is an example of the use of the optical communication device of the present invention. This corresponds to the communication node (12
) is connected by a single optical fiber (11〉).In the figure, (11), (1
2> is a component that is the same as or corresponds to the component in the conventional example.

In the figure, (30) is a remote control (30) for air conditioner adjustment connected to communication node A (hereinafter referred to as A station).
(hereinafter referred to as the remote control). The left neighbor of this A station is 88
, the station next to it is station 0, and the station to the right of station A is station D.

(31) is an air conditioner indoor unit connected to each of stations B, C, and D, each of which has a built-in microcomputer (32).

(33) is a transistor operated by the microcomputer (32), and is a transmission signal output terminal T of each communication node (12).
Output the transmission signal to D. (34) is a commercial power source for driving each air conditioner indoor unit (31), (35) is a battery for the remote control (30), and (36) is a remote control (30).
The built-in microcomputer (37) is a transistor operated by a signal from the microcomputer (36). (38)
(39) is a thermistor installed at the intake port of the air conditioner room II (31) to detect the room temperature, and (39) is the
This is an air conditioner outdoor unit that operates in pair with (31).

This air conditioner control system is installed in a large room, for example.
Three air conditioner indoor units (31) connected to stations , C, and D are arranged separately, and one remote control (30) controls the operation according to temperature, etc. The control signal from the remote control (30) is converted into an optical signal at station A, and the control signal from the left and right B and D
sent to the station.

Communication operations in the control system configured as described above will be described below.

First, the microcomputer (36) activates the transistor (37) according to a temperature signal set by the remote controller (30), and the temperature signal is output as an electrical signal to the transmission signal output terminal TD of the communication node (12). This electric signal is transmitted to the light emitting element (17) inside the communication notebook (12) as described in the explanation of Fig. 1 above.
is photoelectrically converted. The optical signal is transmitted from the first light transmission port (21a) and the second light transmission port (21b) to the B station and the D station, which are located on both sides of the left and right sides of the A station, via an optical fiber (1
1) is optically transmitted through.

In response to this optical signal, at the communication node (12) of station B, a part of the optical signal passes through the light guide path (19) for passing light and is transmitted as it is to the adjacent station 0.

Further, a part of the received light passes through the received light guide path (20) and is transmitted from the light receiving port to the light receiving element (13). The light receiving element (13) converts the light into an electrical signal, and the amplifier circuit (14) further converts it into an electrical signal.
) and input to the received signal input terminal RD.

This input signal is received by the microcomputer (32) in the air conditioner indoor unit (31). The microcomputer (32) synchronizes with this received signal at a predetermined communication speed, and
Generates a signal with a predetermined constant pulse width. and,
The transistor (33) is activated and each communication node (12
) outputs the transmission signal to the transmission signal output terminal TD. Thereafter, the transmitted signal is photoelectrically converted, and the optical signal is optically transmitted to the 0 station and the A station located on both the left and right sides of the B station through the optical fiber (11).

Therefore, the temperature setting signal from the remote controller (30) is transmitted to the 0 station as well as the B station. Moreover, it is energized and transmitted at station B. Therefore, even if several stations are connected to the left side of station 0, the same communication information can be sequentially transmitted in the same way.

Moreover, since each of these stations has a light guide path (19) for passing light, even if station B fails or the commercial power supply (34) is not turned on, the communication signal from station A will be transmitted to the neighboring station. is transmitted to the station.

On the other hand, by connecting a thermistor (38) etc. to the input of the microcomputer (32) of the air conditioner indoor unit (31), the temperature data detected by this thermistor (38) can be converted into an optical signal and fed back to station A. You can also do it.

At station A, this optical signal is photoelectrically converted, amplified, and input to the microcomputer (36) of the remote controller (30). and,
Appropriate air conditioning is performed by comparing the received temperature data with the set temperature data of the remote controller (30) and appropriately controlling the operating status of the fan motor (not shown) or the air conditioner outdoor unit (39). be able to.

Further, the temperature detected by the thermistor (38) of the B station can be displayed on the remote control (30), for example, 27°C.

In this way, if the optical communication device of this embodiment is adopted, various types of optical communications can be performed in both directions between multiple stations by simply connecting each station with a single optical fiber (11). can.

In the above embodiment, the communication node (12) has been described in which the branch light guide section (A> and the photoelectric conversion section (B) are integrated. However, this branch light guide section (A) and the photoelectric conversion section (B) may be separated. Fig. 4 is a circuit diagram showing a communication node of an optical communication device which is another embodiment of the present invention. This figure shows the branch light guide section (A>) and the photoelectric conversion The section (B) is separated into a light guide section (12a) and a photoelectric conversion section (12b).In the figure, (11)
to (23>) are constituent parts that are the same as or correspond to the constituent parts of the above-mentioned conventional example.

In the figure, (40) indicates the first light receiving port (20a> and second light receiving port (20b) of the received light light guide path (20) of the light guide section (12a) and the light receiving element of the photoelectric conversion section (12b). (1
3) is a light-receiving connection part that connects with the part. (41) represents the first light transmitting port (21a> and second light transmitting port (21b) of the transmission light light guide (21) of the light guide section (12a) and the light emitting element (21b) of the photoelectric conversion section (12b). 17) is a light transmission connection section that connects the section.

The communication node (12) of this embodiment also has a light guide path section (12a
) and the photoelectric conversion unit (12b), the configuration becomes the same as that of the communication node (12) of the embodiment described above, and the optical communication operation becomes the same. Therefore, the optical communication device of this embodiment also
It can receive optical signals from both left and right directions, and can transmit optical signals from both directions. Then, a part of the optical signal passes through the light guide path (19) for passing light (
(pass-through), so the same effect as the above embodiment is achieved.

In particular, if a communication node (12) in which the light guide path section (12a> and the photoelectric conversion section (12b) are separated) as in this embodiment is used, the range of configuration of the communication system is expanded, and it can be adjusted according to the purpose of use. The user can select as appropriate.

Incidentally, in each of the above embodiments, the case where the optical communication device is used in an air conditioner control system has been described as an example of use, but the present invention is not limited to this system. For example, due to the characteristics of optical communication that is not affected by electromagnetic noise, it can be widely used in information equipment such as personal computers, factory communication systems such as NC machines, and home automation communication systems for home use. It can be used in the telecommunications industry.

[Effects of the Invention] As explained above, the optical communication device of the present invention includes a branching light guide path section that connects to an optical fiber for optical communication, a light guide path for passing light through which an optical signal can pass, and a first light receiving port. and a light guide path for receiving light having a second light receiving port, and a light guide path for transmitting light having a first light sending port and a second light sending port. Optical signals from the light receiving port and the second light receiving port are photoelectrically converted by the light receiving element, and the electrical signals are amplified by the amplifier circuit, and the electrical signals are photoelectrically converted by the light emitting element, and the optical signals are converted from the light receiving port to the first light receiving port and the second light receiving port. By emitting light at the light transmitting port, it is possible to receive optical signals transmitted in a single optical fiber in both directions, converting the optical signals into photoelectric signals, and photoelectrically converting various electrical signals into optical signals. Since it is possible to transmit data in both directions, single-wire bidirectional optical communication is possible without forming a loop for optical communication. Moreover, a part of the optical signal passes through the light guide for passing light and is transmitted to the phosphor layer, etc., so even if the station in question fails, the optical signal can be transmitted to the phosphor layer. Improves the reliability of communication systems. Furthermore, since operations such as optical signal branching, signal extraction, and light transmission can be performed without using a transmission prism, the device can be made very inexpensive and compact.

[Brief explanation of the drawing]

FIG. 1 is a circuit diagram showing a communication notebook of an optical communication device according to an embodiment of the present invention, FIG. 2 is a cross-sectional view showing the vicinity of the connection part of the branch light guide path of the communication node in FIG. 1, and FIG. 4 is a circuit diagram showing a control system for an air conditioner which is an example of the use of the optical communication device of the present invention, FIG. 4 is a circuit diagram showing a communication notebook of the optical communication device which is another embodiment of the present invention, and FIG. 6 is a plan view showing a state in which a transmission prism of an optical switch used in a conventional optical communication device is inserted into the optical path and a state in which the transmission prism is removed from the optical path. FIG. 6 is a configuration diagram showing a conventional optical transmission system. be. In the figure, 11: optical fiber 13: light receiving element, 14: amplifier circuit, 17: light emitting element, 19: light guide path for passing light, 20: light guide path for received light, 20a: first light receiving port,
20b: second light receiving port, 21: light guide path for transmitted light, 21
a: first light transmission port, 21b: second light transmission port, 22: connection portion, 23: connection portion A: branch light guide path portion,
B: Photoelectric conversion section. In addition, in the figures, the same reference numerals and the same symbols indicate the same or equivalent parts.

Claims (1)

[Scope of Claims] Both connecting parts connected to optical fibers for optical communication are branched into three systems, and one of the three systems allows optical signals to pass from both directions between the two connecting parts. a light guide path for passing light, another light guide path for receiving light having a first light receiving port and a second light receiving port each receiving optical signals from both the connection portion directions; a transmitting light light guide path in which the system has a first light transmitting port and a second light transmitting port, each of which transmits an optical signal in the direction of both the connection portions; and a first light receiving port of the receiving light light guide path. and a light-receiving element that receives an optical signal from the second light-receiving port and converts it into an electrical signal, an amplifier circuit that amplifies the electrical signal from the light-receiving element, and a light guide path for converting the electrical signal into an optical signal for transmitting light. An optical communication device comprising: a photoelectric conversion section having a light emitting element that emits an optical signal at a first light transmission port and a second light transmission port of the optical communication device.