JPH06125115A - Light transmitting/receiving module - Google Patents

Abstract

PURPOSE:To provide a light transmitting/receiving module which enables highly precision output control by preventing light by outside resonance of a light emitting means and receive-signal from being injected to a monitoring photodi ode for controlling output of a light emitting means for transmission. CONSTITUTION:A first photodiode PD1 which receives light passing through a waveguide path 11a of a super luminescent diode (hereinafter called SLD) 11 is provided, a branching means for branching a specified wavelength band region including a wavelength used for transmission among light emitted at the SLD 11 and other wavelength band region, an output value of light branched by the branching means is detected by a second photodiode PD 2 and an APC 17 which controls SLD 11 based on the detected value of the second photodiode APD 2 are provided. A detected value of the first photodiode PD 1 is corrected based on the detected value of the second photodiode PD2 and a receive signal from an optical fiber 3 is acquired.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a coupling device between a light emitting element such as a semiconductor laser and an optical fiber used in the field of optical communication and the like, and more particularly to an optical transceiver module.

[0002]

2. Description of the Related Art The optical system of an optical transceiver module generally has a structure as shown in FIG. FIG. 11 shows a single-core bidirectional optical communication transceiver module 1 described in Japanese Patent Application Laid-Open No. 4-96437. The optical transceiver module 1 includes a light emitting element (hereinafter referred to as LD) 2 and an optical fiber 3 forming an optical input / output section is connected. A deflection beam splitter 4 is arranged between the LD 2 and the optical fiber 3. This deflection beam splitter 4
Transmits the laser light from the LD 2 and reflects the laser light from the optical fiber 3 in a direction of about 45 ° with respect to the transmitted light.

A light receiving element (hereinafter referred to as PD) is provided at the arrival position of the laser beam reflected by the deflecting beam splitter 4.
5 is arranged and configured to convert an optical signal transmitted from the optical fiber 3 into an electric signal.

Further, lenses 7 and 8 for focusing light and diaphragms 9a, 9b and 9c are arranged in the optical path.

[0005]

In the conventional optical transmission / reception module as described above, the PD for monitoring (not shown) is provided on the back side of the LD, and the output value of the LD detected by the PD for monitoring is provided. By this, the LD is controlled. In the configuration in which the laser light is detected behind the LD and detects the laser output, the laser light incident on the monitor PD resonates with the lens or the end face of the optical fiber. Since different laser beams are also incident, the detection value becomes inaccurate and the LD cannot be controlled accurately.

The present invention has been made in view of the above problems, and an optical system is configured so that only the output light from the light emitting means is incident on the light receiving means for monitoring, and the output is controlled by accurate output control. It is an object of the present invention to provide an optical transmitter / receiver module that is extremely stable, and that keeps the size of the optical transmitter / receiver module equal to that of a conventional structure to prevent an increase in size.

[0007]

According to a first aspect of the present invention, transmitted / received signal light incident on an optical input / output unit for inputting / outputting an optical signal is emitted in a predetermined wavelength band without resonating, and
The light input / output unit and the light emitting unit are provided with a light emitting unit having a waveguide for guiding the received signal light from the optical input / output unit, and a first light receiving unit for receiving the received signal light transmitted through the waveguide of the light emitting unit. And optical transmission / reception provided with a demultiplexing means for demultiplexing the wavelength light within the predetermined wavelength band and the other wavelength light, and a second light receiving means for receiving the other wavelength light demultiplexed by the demultiplexing means. In module.

Further, the invention according to claim 2 is an input / output for inputting / outputting an optical signal for transmitting / receiving a first wavelength and transmitting / receiving a second wavelength different from the first wavelength. First light having a wavelength band wider than a predetermined wavelength band, which emits light including a transmission signal light having a first wavelength, which does not resonate, and which has a waveguide for guiding a reception signal having a first wavelength.
Light emitting means is provided, and demultiplexing means is provided between the light input / output unit and the first light emitting means for demultiplexing an optical signal in a predetermined wavelength band including the first wavelength and light of another wavelength including the second wavelength, The first light receiving means for detecting the received signal light of the first wavelength light transmitted through the waveguide of the first light emitting means is provided, and the other wavelength light not including the first wavelength demultiplexed from the transmission signal light by the demultiplexing means is provided. A second light receiving means for receiving the second wavelength is provided, and the second wavelength is emitted toward the light input / output unit through the third light receiving means and the demultiplexing means for receiving the second wavelength demultiplexed from the received signal light by the demultiplexing means. It is in the optical transceiver module provided with the second light emitting means.

The invention according to claim 3 is an input / output for inputting / outputting an optical signal for transmitting / receiving a first wavelength and transmitting / receiving a second wavelength different from the first wavelength. First light having a wavelength band wider than a predetermined wavelength band, which emits light including a transmission signal light having a first wavelength, which does not resonate, and which has a waveguide for guiding a reception signal having a first wavelength.
Light emitting means is provided, and demultiplexing means is provided between the light input / output unit and the first light emitting means for demultiplexing an optical signal in a predetermined wavelength band including the first wavelength and light of another wavelength including the second wavelength, The first light receiving means for detecting the received signal light of the first wavelength light transmitted through the waveguide of the first light emitting means is provided, and the other wavelength light not including the first wavelength demultiplexed from the transmission signal light by the demultiplexing means is provided. A second light receiving means for receiving the second wavelength, and the second wavelength is emitted toward the light input / output portion through the third light receiving means or the light demultiplexing means for receiving the second wavelength demultiplexed from the received signal light by the demultiplexing means. It is in the optical transceiver module provided with the second light emitting means.

Further, the invention according to claim 4 further comprises an output control means for controlling the output of the light emitting means based on the detection value of the second light receiving means.
The optical transceiver module described in 1.

Further, the invention according to claim 5 further comprises a correction means for correcting the signal received by the first light receiving means based on the detection value of the second light receiving means to obtain a received signal. The optical transceiver module according to claim 2 or claim 3 or claim 4.

According to a sixth aspect of the present invention, a waveguide for oscillating and outputting the transmission signal light incident on the optical input / output unit to which the optical signal is input in the resonator and for guiding the reception signal light. And a first light receiving means for receiving the received signal light transmitted through the waveguide of the light emitting means, and a part of the transmission signal is provided between the light input / output section and the light emitting means. A second means for providing a branching means for branching the light and receiving the light branched by the branching means to detect the light intensity of the light emitting means
The light receiving means is provided, and the output control means for controlling the output of the light emitting means based on the detection value of the second light receiving means is provided.
An optical transceiver module provided with a time division control means for controlling the timing of transmission and reception with the light receiving means.

[0013]

According to the invention as set forth in claim 1, there is provided a waveguide which emits the transmission signal light incident on the optical input / output unit without resonating in a wavelength band wider than a predetermined wavelength band and guides the reception signal light. By providing the light emitting means having the waveguide, the second light receiving means can receive the received signal light from the optical input / output unit through the waveguide. Therefore, the first light receiving means for receiving can be provided at the same position as the light receiving element for monitoring which is conventionally provided at the rear part of the semiconductor laser. Further, when controlling the optical output of the light emitting means, an electric signal of the second light receiving means for detecting and photoelectrically converting other wavelength light demultiplexed by the demultiplexing means other than the predetermined wavelength band unnecessary for communication. Can be carried out based on

According to the second aspect of the invention, since the first light receiving means is used for receiving the first wavelength, the second light receiving means can be used for monitoring for output control. . A third light receiving means for receiving the second wavelength and a second light emitting means for emitting the second wavelength may be provided at a position facing the reflection surface of the reception signal of the branching means. Since the second light receiving means can detect the optical output of the wavelength band not required for optical communication in the output light of the first light emitting means, the output light can be effectively used. Further, since the second light receiving means receives the light obtained by demultiplexing the other wavelength light from the transmission signal light by the demultiplexing means, it is not affected by the reflected return light from the surface of the optical component. As a result, the optimum signal for output control can be obtained.

Further, according to the third aspect of the invention, since the first light receiving means is used for receiving the first wavelength, the second light receiving means can be used for monitoring for output control. . A third light receiving means for receiving the second wavelength or a second light emitting means for emitting the second wavelength can be provided at a position facing the reflection surface of the reception signal of the demultiplexing means. Since the second light receiving means can detect the optical output of the wavelength band not required for optical communication in the output light of the first light emitting means, the output light can be effectively used. Further, since the second light receiving means receives the light obtained by demultiplexing the other wavelength light from the transmission signal light by the demultiplexing means, it is not affected by the reflected return light from the surface of the optical component. As a result, the optimum signal for output control can be obtained.

According to the invention described in claim 4, it is possible to obtain the operation described in claim 1, claim 2 or claim 3, and further, based on the detection value of the second light receiving means, the light emitting means. By providing the output control means for controlling the output of the output signal, the output can be controlled without being affected by the reflected return light of the output signal light on the surface of the optical component.

According to the invention described in claim 5, it is possible to obtain the operation described in claim 1 or claim 2, or claim 3 or claim 4, and further to detect the value detected by the second light receiving means. By providing the correcting means for correcting the received signal received by the first light receiving means, the received signal light from the optical input / output unit can be received even while the light emitting means is transmitting.

According to the invention described in claim 6, the second light receiving means can receive the received signal light from the light input / output portion through the light emitting means. As a result, the first light receiving means for reception can be provided at the same position as the light receiving element for monitoring, which is conventionally provided at the rear portion of the semiconductor laser.
Further, the output control means for controlling the light output of the light emitting means,
This is performed based on the detection value of the second light receiving means for detecting the light obtained by branching a part of the transmission signal by the branching means. That is, the second
Since the light receiving means detects light on the output side of the transmission signal, it is possible to detect the output of the light emitting means without being affected by the reflected return light from the surface of the optical component.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described with reference to FIGS. The optical transmission / reception module 1 shown in FIG. 1 is capable of simultaneous bidirectional communication, and is provided with a light emitting means facing the optical fiber 3 as an optical input / output unit. This light emitting means is, for example, a super luminescent diode (hereinafter referred to as SLD) 11, which is a light emitting element having no optical resonator. The light emitting portion of the SLD 11 directly forms the waveguide 11a. That is, the SLD 11 has both the property of a waveguide that transmits light and the property of outputting light in a wavelength band wider than a predetermined wavelength band when excited by an external input.

Here, the predetermined wavelength band means a narrow band including a wavelength of 1.3 μm generally used for optical communication, for example.

Demultiplexing means is provided between the optical fiber 3 and the SLD 11. This demultiplexing means is, for example, the interference filter 13, and the function of the demultiplexing will be described with reference to FIG.

The output distribution with respect to wavelength of the light output from the SLD 11 is indicated by A in the figure. Then, the light output from the SLD 11 passes through the interference filter 13 and passes through the optical fiber 3
When incident on, the transmission signal light of the predetermined wavelength band shown by B in the figure is narrowed. The output distribution indicated by C in the figure is the received signal light emitted from the optical fiber 3. The shaded area D indicates the interference filter 1
It is the other wavelength light which is demultiplexed by 3.

That is, the interference filter 13 transmits light in the predetermined wavelength band B used as the transmission signal light and reflects other wavelength light D, for example, in a direction substantially orthogonal to the transmission signal light. ing.

A condenser lens 14 is inserted between the SLD 11 and the interference filter 13. The signal light received from the optical fiber 3 is condensed by the condenser lens 14, and is arranged so as to be focused on the incident end face of the SLD 11. The transmission signal light output from the SLD 11 is also arranged so as to be focused on the incident end face of the optical fiber 3. Here, the output peaks of both the reception signal light and the transmission signal light are set to a wavelength of 1.3 μm, for example.

Further, a first photodiode PD1 as a first light receiving means is provided at a position where the received signal light from the optical fiber 3 which has passed through the waveguide 11a of the SLD 11 reaches. SLD11 and first photodiode PD1
A spherical lens 15 for collecting light is inserted between and.

On the other hand, a second photodiode PD2 as a second light receiving means is provided at a position where light of another wavelength reflected by the interference filter 13 reaches.

The drive unit 16 for controlling the above-mentioned optical system will be described below.

The detection signal of the second photodiode PD2 is input to an automatic output control section (hereinafter referred to as APC) 17 as output control means. The output signal from the APC 17 is input to the drive circuit 18. The drive circuit 18 is a circuit for driving the SLD 11.
That is, the APC 17 is configured to compare the output detection value at the standard output of the SLD 11 with the output detection value during driving, and feedback control the drive circuit 18 according to the comparison result.

Here, an electric signal (transmission) is input to the drive circuit 18 from the transmission output section E1, and the drive circuit 18 excites the SLD 11 in response to the input of this electric signal (transmission). There is.

In this way, the APC 17 and the drive circuit 18 are configured so that the SLD 11 is always driven with a stable output. Further, as the other wavelength light D detected by the second photodiode PD2 for drive control, as shown in FIG. 2, since the wavelength band light deviating from the predetermined wavelength band B used for the transmission signal light is used, Efficient drive control can be performed without the problem of output reduction.

The receiving device 19 for converting the received signal light received by the above-mentioned optical system into an electric signal (reception) input to the reception input section E2 will be described below.

A first amplifier 20 for amplifying a reception signal photoelectrically converted by the first photodiode PD1 is provided, and a second amplifier 21 for amplifying a detection signal photoelectrically converted by the second photodiode PD2 is provided. Then, the first and second amplifiers 20 and 21 are configured to input their amplified signals to the correction circuit 22. Here, as a correction function, the correction circuit 22 inverts the detection signal detected by the second photodiode PD2 by inverting the positive and negative values of the reception signal value received by the first photodiode PD1 and synthesizes them to be originally output from the optical fiber 3. The same electric signal (reception) as that obtained from the received signal light is obtained.

3 and 4 show changes in the signal strength of the electric signals of the transmission output section E1 and the reception input section E2.

FIG. 3A is a graph showing the change in signal intensity of the received signal light output from the optical fiber 3 with respect to time. Further, FIG. 6B is a graph showing a change in signal intensity of the transmission signal light output from the SLD 11 with respect to time.

Then, FIG. 6C is a graph showing the change in the signal intensity of the light detected by the first photodiode PD1 with respect to time.

Here, the light input to the first photodiode PD1 is light in which the transmission signal light output from the SLD 11 and the reception signal light output from the optical fiber 3 are combined.

FIG. 6E is a graph showing the change in signal strength of the transmission signal received by the PD 2 with respect to time.
FIG. 6F shows a correction signal obtained by synthesizing the detection signal of the PD 1 of FIG. With this correction, it is possible to obtain the same waveform as the received signal (b) output from the optical fiber 3.

FIG. 6 (g) is a graph showing the change in the signal strength of the transmission signal input to the optical fiber 3 with respect to time.

The respective parts of the driving device 16 and the receiving device 19 shown in FIG. 1 and the corrugated drawings of FIGS. 3 and 4 will be described below in association with each other.

First, the drive device 16 will be described.
The optical output detected by the second photodiode PD2 is shown in FIG.
The light output is shown in FIG.
It is a hatched portion indicated by D in the figure. That is, SLD11
In the wide emission wavelength band A, the light D for the wavelength band that is not directly necessary for the transmission signal is used for detecting the light intensity.
Therefore, the APC 17 can efficiently use the optical output A of the SLD 11, and the drive circuit 18 causes the transmission output unit E1 to operate.
The SLD 11 is driven and controlled in conjunction with the electric signal (transmission) from the.

In the receiver 19, the correction circuit 22 performs signal correction processing based on the signal (c) detected by the first photodiode PD1 and the signal (a) detected by the second photodiode PD2, Obtain an electrical signal (reception). That is, the first and second photodiodes PD1 and PD2
The signals detected in step (1) are level-adjusted by the amplifiers 20 and 21 provided for the respective signals, and the correction circuit 22 inverts the signal (a) with respect to the signal (c) and synthesizes them. Obtain the difference signal (f). This difference signal (f) is output as an electric signal (reception).

Here, the reception signal (b) output from the optical fiber 3 passes through the SLD 11 and reaches the first photodiode PD1, and is combined with the output light of the SLD 11 to form a combined signal (c). . The correction circuit 22 corrects the combined light, so that the optical fiber 3
The same signal (f) as the signal (b) output from can be obtained.

The signal (g) is a transmission signal input to the optical fiber 3.

In the optical transmission / reception module 1 configured as described above, the first photodiode PD1 is provided at a position corresponding to the monitoring photodiode provided behind the semiconductor laser of the conventional optical communication module, This is a structure for detecting a received signal.

According to this optical transceiver module 1, the second photodiode PD2 for monitoring can be housed in a position where it does not receive the reflected return light, although it is an optical system housed in the same space as the conventional one.

Further, the other wavelength light which is not necessary for the transmission signal is demultiplexed by the interference filter 13, and the other wavelength light is divided into the second wavelength.
Detected by the photodiode PD2, this detected value is A
It is used for the PC 17 to control the accurate output of the SLD 11.
That is, the output of the SLD 11 can be efficiently used.

Further, by using the detected value of the second photodiode PD2 in the correction circuit 22 and correcting the received signal, an accurate electric signal (reception) can be obtained. As a result, it is possible to realize accurate reception despite simultaneous single-core bidirectional transmission and reception.

It is also possible to perform time division multiplex communication by providing a timing controller (not shown) in the receiver 19 of the optical transceiver module 1 without providing the correction circuit 22 and the amplifier 21.

A second embodiment of the present invention will be described below with reference to FIGS. 2 to 5. The basic structure is an optical transceiver module capable of simultaneous single-core bidirectional transmission / reception similar to that of the first embodiment. It is 1.

An optical fiber 3 as an optical input / output unit is connected to the optical transceiver module 1. The optical fiber 3 is provided with the first light emitting means facing each other. The first light emitting means is, for example, a super luminescent diode (hereinafter referred to as SLD) 11, which is a light emitting element having no optical resonator. The light emitting portion of the SLD 11 directly forms the waveguide 11a. That is, SLD11
Has a property of transmitting light and a wavelength band A wider than the predetermined wavelength band B shown in FIG. 2 when excited by an external input.
It also has the property of outputting light.

Here, the predetermined wavelength band B is the first wavelength λ1.
(For example, the wavelength generally used for optical communication: 1.3μ
The narrow band including m) is shown. Further, the optical fiber 3 is capable of transmitting the first wavelength λ1 and the second wavelength (for example, a wavelength generally used for transmitting an image signal or the like in optical communication: 1.55 μm).

Demultiplexing means is provided between the optical fiber 3 and the SLD 11. This demultiplexing means is, for example, the interference filter 13, and the function of the demultiplexing will be described with reference to FIG.

The light output from the SLD 11 has an output distribution indicated by A in the figure with respect to wavelength. Then, the light output from the SLD 11 passes through the interference filter 13 and passes through the optical fiber 3
When incident on, the transmission signal light of the predetermined wavelength band shown by B in the figure is narrowed. The output distribution indicated by C in the figure is the received signal light emitted from the optical fiber 3. The shaded area D indicates the interference filter 1
It is the other wavelength light which is demultiplexed by 3.

That is, the interference filter 13 is constructed so as to transmit the light of the predetermined wavelength band used as the transmission signal light and reflect the other wavelength light in the direction orthogonal to the transmission signal light, for example.

A condenser lens 14 is inserted between the optical fiber 3 and the interference filter 13. The signal light received from the optical fiber 3 is condensed by the condenser lens 14, and is arranged so as to be focused on the incident end face of the SLD 11. The transmission signal light output from the SLD 11 is also arranged so as to be focused on the incident end face of the optical fiber 3.

Here, the received signal light transmitted by the optical fiber 3 transmits two kinds of signals having wavelengths of 1.3 μm and 1.55 μm, for example. Further, the SLD 11 emits transmission signal light in a wide wavelength band including a wavelength of 1.3 μm, for example. Note that the light intensity distribution of the second wavelength (for example, wavelength light corresponding to 1.55 μm) λ2 is not shown in FIG.

The interference filter 13 reflects only the 1.55 μm wavelength light of the received signal light transmitted from the optical fiber 3 in a direction orthogonal to the received signal light, for example. In addition, the interference filter 13 transmits only a narrow band (the predetermined wavelength band) including the 1.3 μm wavelength light in the transmission signal light from the SLD 11 and reflects the other wavelength light in a direction orthogonal to the transmission signal light, for example. To do.

Further, a first photodiode PD1 as a first light receiving means is provided at a position where the received signal light from the optical fiber 3 which has passed through the waveguide 11a of the SLD 11 reaches. SLD11 and first photodiode PD1
A spherical lens 15 for collecting light is inserted between and.

On the other hand, the second photodiode PD2 is provided at a position where the other wavelength light reflected by the interference filter 13 in the transmission signal light of the SLD 11 reaches.

Further, the third photodiode PD3 is located at a position where the 1.55 μm wavelength light reflected by the interference filter 13 among the received signal light of the optical fiber 3 reaches.
Is provided.

Then, the third photodiode PD3
Is photoelectrically converted to output an electric signal (reception) to the second reception input unit E3.

That is, the SLD 11 causes the first wavelength λ
1 is transmitted, and the first photodiode PD1 receives the first wavelength λ1 from the optical fiber 3. further,
The third photodiode PD3 receives the second wavelength λ2.

The driving device 16 and the receiving device 19 have the same configurations as those of the first embodiment, and the description thereof will be omitted.

With the above configuration, for example, the transmission and reception of the audio signal using the first wavelength λ1 and the reception of the TV image signal using the second wavelength λ2 can be performed by the single-core optical fiber 3. it can.

Further, instead of the third photodiode PD3, a second wavelength λ2 can be transmitted by providing, for example, a laser diode (not shown) as the second light emitting means. In this case, the electric signal from the second transmission output unit (not shown) is the transmission signal.

Further, instead of the third photodiode PD3, by providing a light emitting / receiving element (not shown) which also serves as the third photodiode PD3 and the second light emitting means,
Transmission and reception with the second wavelength λ2 are possible. In this case, in addition to the electric signal (reception) to the second reception input unit E3, it is necessary to provide a second transmission output unit (not shown) for the electric signal (transmission).

It is also possible to perform time division multiplex communication by providing a timing controller (not shown) in the receiver 19 of the optical transceiver module 1 without providing the correction circuit 2 and the amplifier 21.

FIG. 6 shows a third embodiment of the present invention.
This is a modification of the second embodiment in which the number of condenser lenses 14 is two and the arrangement is changed. Since the effect of implementation is almost the same as that of the second embodiment, it is only shown in the figure and the description is omitted.

A fourth embodiment of the present invention will be described below with reference to FIGS. 2 to 4 and 7.

The optical transceiver module 1 shown in the figure is for performing time division multiplex communication. In other words, it is different from the optical transceiver modules capable of simultaneous bidirectional transmission / reception disclosed in the first to third embodiments.

The optical transceiver module 1 is provided with a first light emitting means facing the optical fiber 3. This first
The light emitting means is, for example, a super luminescent diode (hereinafter referred to as SLD) 11, which is a light emitting element having no optical resonator. The light emitting portion of the SLD 11 directly forms the waveguide 11a. That is, the SLD 11 has both the property of a waveguide that transmits light and the property of outputting light in a wavelength band wider than a predetermined wavelength band when excited by an external input.

Here, the predetermined wavelength band is a wavelength band shown by B in FIG. 2, and is a narrow band including a wavelength of 1.3 μm generally used for optical communication.

Demultiplexing means is provided between the optical fiber 3 and the SLD 11. This demultiplexing means is, for example, the interference filter 13, and the function of the demultiplexing will be described with reference to FIG.

The output distribution with respect to wavelength of the light output from the SLD 11 is indicated by A in the figure. Then, the light output from the SLD 11 passes through the interference filter 13 and passes through the optical fiber 3
When incident on, the transmission signal light of the predetermined wavelength band shown by B in the figure is narrowed. The output distribution indicated by C in the figure is the received signal light emitted from the optical fiber 3. The shaded area D indicates the interference filter 1
It is the other wavelength light which is demultiplexed by 3.

That is, the interference filter 13 is constructed so as to transmit the light of the predetermined wavelength band B used as the transmission signal light and reflect the other wavelength light D, for example, in a direction substantially orthogonal to the transmission signal light. ing.

A condenser lens 14 is inserted between the SLD 11 and the interference filter 13. The signal light received from the optical fiber 3 is condensed by the condenser lens 14, and is arranged so as to be focused on the incident end face of the SLD 11. The transmission signal light output from the SLD 11 is also arranged so as to be focused on the incident end face of the optical fiber 3. Here, the output peaks of both the reception signal light and the transmission signal light are set to a wavelength of 1.3 μm, for example.

Further, a first photodiode PD1 as a first light receiving means is provided at a position where the received signal light from the optical fiber 3 which has passed through the waveguide 11a of the SLD 11 reaches. SLD11 and first photodiode PD1
A spherical lens 15 for collecting light is inserted between and.

On the other hand, a second photodiode PD2 is provided at a position where the light of another wavelength reflected by the interference filter 13 reaches.

The drive device 16 for controlling the above-mentioned optical system will be described below.

The detection signal of the second photodiode PD2 is input to the automatic output control unit (hereinafter referred to as APC) 17. The output signal from the APC 17 is input to the drive circuit 18. This drive circuit 18 is an SLD
11 is a circuit for driving 11. That is, APC17
Compares the output detection value at the standard output of the SLD 11 with the output detection value during driving, and drives the drive circuit 18 according to the comparison result.
Is configured to be feedback controlled.

Here, the electric signal (transmission) from the transmission output section E1 is inputted to the drive circuit 18 through the timing controller TC, and the time division control of the timing controller TC is added to the input of this electric signal (transmission). ,
The drive circuit 18 excites the SLD 11 in a time division manner. Then, the APC 17 and the drive circuit 18
Thus, the SLD 11 is always driven with a stable output.

Further, as shown in FIG. 2, the other wavelength light detected by the second photodiode PD2 for drive control uses the wavelength band light D deviated from the predetermined wavelength band B used for the transmission signal light. Therefore, efficient drive control can be performed.

The receiving device 19 for converting the received signal light received by the above-mentioned optical system into an electric signal (reception) input to the first reception input section E2 will be described below.

An amplifier 20 for amplifying the detection signal from the first photodiode PD1 is provided. Then, the amplified signal of the amplifier 20 is output as an electric signal (reception) that is input to the first reception input unit E2 through the timing controller TC. That is, the reception timing of the electric signal (reception) to the first reception input unit E2 and the reception timing of the electric signal (transmission) from the transmission output unit E1 are controlled by the timing controller TC, and time division is performed without simultaneous communication with each other. Multiplex communication is realized.

FIG. 3A is a graph showing the change in the signal intensity of the received signal light output from the optical fiber 3 with respect to time. Further, FIG. 6B is a graph showing a change in signal intensity of the transmission signal light output from the SLD 11 with respect to time.

Further, FIG. 4 (e) is a graph showing the change in the signal strength of the transmission signal received by the PD2 with respect to time. Then, FIG. 6G is a graph showing the change in the signal strength of the transmission signal input to the optical fiber 3 with respect to time.

Hereinafter, each part of the driving device 16 and the receiving device 19 shown in FIG. 7 and the corrugated drawings of FIGS. 3 and 4 will be described in association with each other.

First, the drive device 16 will be described.
The optical output detected by the second photodiode PD2 is shown in FIG.
The light output is shown in FIG.
It is a hatched portion indicated by D in the figure. That is, SLD11
The other wavelength light D that is not directly necessary for the transmission signal in the wide emission wavelength band A is used for detecting the light intensity. Therefore, the optical output of the SLD 11 can be efficiently used. Then, the drive circuit 18 causes the timing controller T
The SLD 11 is driven and controlled in conjunction with an electric signal (transmission) from the transmission output unit E1 input through C.

Further, the receiving device 19 obtains an electric signal (reception) to the reception input section E2 by passing the signal shown in FIG. 7B detected by the first photodiode PD1 through the timing controller TC. That is, the timing controller TC controls the electric signals (transmission) and the electric signals (reception) so that they are transmitted and received in a time-division state with each other, and bidirectional simultaneous communication is not performed.

The optical transmission / reception module 1 configured as described above receives the received signal by the first photodiode PD1 corresponding to the monitoring photodiode provided behind the semiconductor laser of the conventional optical communication module. It has a structure to detect. Further, the second photodiode PD2 can be housed in a position where it does not receive the reflected return light in the same space as the conventional optical communication module.

The optical transmission / reception module 1 capable of arranging an optical system similar to that of the conventional structure has a structure for improving the performance, and it is not necessary to increase the size of the module itself.

In addition, other wavelength light D which is not necessary for the transmission signal
Is separated by the interference filter 13, the other wavelength light D is detected by the second photodiode PD2, and the detected value is used for the APC 17 to accurately control the output of the SLD 11. That is, the output of the SLD 11 can be used efficiently and the output of the SLD 11 can be controlled to be constant.

The present invention is not limited to the above embodiments. For example, in the embodiment, the first wavelength λ
1 is 1.3 μm light, and the second wavelength λ2 is 1.55 μm.
However, the light is not limited to this, and each light can be used for optical communication, that is, the light can be detected by the first photodiode PD1 and the second photodiode PD2. The effect of can be obtained.

The demultiplexing means is the interference filter 13, but the demultiplexing means is not limited to this, and the same effect can be obtained if it is an optical system capable of demultiplexing the predetermined wavelength band and other wavelengths as described above. it can.

The fifth embodiment of the present invention will be described below with reference to FIG.

The optical transceiver module 1 shown in the figure is for performing time division multiplex communication.

The optical transmission / reception module 1 is provided with a first light emitting means facing the optical fiber 3 as an input / output section. The first light emitting means is, for example, a laser diode (hereinafter referred to as LD) 31, which is a semiconductor laser having an optical resonator. In this LD 31, a waveguide 31a is formed between the reflection films forming the resonator. That is,
The LD 31 has both the property of a waveguide that transmits light and the property of outputting laser light in a predetermined wavelength band when excited by an external input.

Here, the predetermined wavelength band is a narrow band including a wavelength of 1.3 μm generally used for optical communication.

A branching means is provided between the optical fiber 3 and the LD 31. The branching means is, for example, the beam splitter 30, and a part of the transmitted light is, for example, 45 °.
It has an interference film that branches in an inclined direction. Also, LD
The condenser lens 14 is provided between the beam splitter 31 and the beam splitter 30.
Has been inserted. The signal light received from the optical fiber 3 is condensed by the condenser lens 14 and is arranged so as to be focused on the incident end face of the LD 31. The transmission signal light output from the LD 31 is also arranged so as to be focused on the incident end face of the optical fiber 3. Here, the output peaks of both the reception signal light and the transmission signal are set to a wavelength of 1.3 μm, for example.

Further, a first photodiode PD1 as a first light receiving means is provided at a position where the received signal light of the optical fiber 3 which has passed through the waveguide 31a of the LD 31 reaches. A spherical lens 15 for condensing light is inserted between the LD 31 and the first photodiode PD1.

On the other hand, a second photodiode PD2 is provided at a position where a part of the transmission signal light reflected by the beam splitter 30 reaches.

A drive device 1 for controlling the above-mentioned optical system
6 will be described.

The detection signal of the second photodiode PD2 is input to the automatic output controller (hereinafter referred to as APC) 17. The output signal from the APC 17 is input to the drive circuit 18. This drive circuit 18 is LD3
1 is a circuit for driving 1. That is, the APC 17 compares the output detection value at the standard output of the LD 31 with the output detection value during driving, and feedback-controls the drive circuit 18 according to the comparison result.

Here, an electric signal (transmission) which is a transmission signal from the transmission output section E1 is input to the drive circuit 18 through the timing controller TC, and the time division control of the timing controller TC is input to the input of this electric signal (transmission). Is added, the drive circuit is adapted to excite the LD 31 in a time division manner. The LD 31 is always driven by the APC 17 and the drive circuit 18 with a stable output.

The receiving device 19 for converting the received signal light received by the above optical system into an electric signal (reception) will be described below.

An amplifier 20 for amplifying the detection signal of the first photodiode PD1 is provided. Then, the amplified signal of the amplifier 20 is output as an electric signal (reception) to the reception input section E2 through the timing controller TC. That is, the communication timing of the reception signal and the transmission signal is controlled by the timing controller TC,
Time division multiplex communication is realized without simultaneous communication with each other.

The optical transmission / reception module 1 configured as described above detects the received signal by the first photodiode PD1 corresponding to the monitoring photodiode provided behind the semiconductor laser of the conventional optical communication module. It is structured to Then, the second photodiode PD2 can be housed in a position that does not receive the reflected return light in the same space as the conventional optical communication module. That is, accurate feedback control of the LD 31 can be performed.

Since the optical transceiver module 1 in which the optical system can be arranged similarly to the conventional structure can improve the performance, it is not necessary to increase the size of the module itself.

FIG. 9 shows a sixth embodiment of the present invention,
The same optical system as that of the fifth embodiment shown in FIG. 8 is provided with a driving device 16 and a receiving device 19 capable of simultaneous transmission and reception. The driving device 16 is the second photodiode PD.
2 includes an APC 17 that receives a signal from the device 2 and a drive circuit 18. The APC 17 controls the drive circuit 18 based on the detection signal from the second photodiode PD2. That is, the output of the LD 31 is controlled based on the detection value of the second photodiode PD2. When the transmission signal is input to the drive circuit 18, the LD3
1 outputs a transmission signal.

Further, the receiving device 19 comprises an amplifier 20 for amplifying the detection signal of the first photodiode PD1 and an amplifier 21 for amplifying the detection signal of the second photodiode PD2, and further amplification by the amplifiers 20 and 21. A correction circuit 22 that corrects the detected signal thus obtained is provided.
The correction circuit 22 combines the detection signal of the first photodiode PD1 with the detection signal of the second photodiode PD2 by inverting the positive and negative values and combining them to extract only the reception signal from the optical fiber 3. The reception signal thus corrected is output as a reception signal to the reception input section E2.

With the configuration as described above, it is possible to accurately control the transmission output while preventing the device from becoming large, and it is possible to perform simultaneous transmission / reception with the communication signals of the same wavelength.

The light input / output unit of each embodiment is not limited to the optical fiber 3 and may be an optical waveguide or a photoelectric element capable of inputting / outputting an optical signal. In other words, it may be any object that allows the optical transceiver module 1 to perform optical communication.

Further, the correction circuit 22 in the above embodiment is configured to correct the reception signal based on the signal from the transmission output section E1 without using the detection signal of the second photodiode PD2. Can also be considered.

Next, a seventh embodiment will be described with reference to FIG. The basic structure of the optical transmission / reception module 1 shown in the figure is the same as that described in the third embodiment.
Is added, only the main part will be illustrated and described.
This transparent member G is bonded to a glass block 13a provided with an interference filter 13 as a demultiplexing means. The transparent member G is formed in a cylindrical shape, and one end surface of the transparent member G is airtightly joined to the glass block 13a.

Here, the glass block 13a and the transparent member G are bonded to each other with an adhesive or the like. For example, when an adhesive is used, it is transparent and has the same or substantially the same refractive index as the glass block 13a and the transparent member G.

The transparent member G is further provided with an elastic sleeve S.
One end side of the is externally fitted.

That is, the elastic sleeve S is elastically fastened and fixed along the outer peripheral surface of the transparent member G. The outer diameter of the elastic sleeve S is transparent to the transparent member G.
The ferrule F formed substantially the same as the above is inserted so that it can be inserted and removed. In this ferrule F, the optical fiber 3 is inserted in the center part, and the end face is airtightly joined to the transparent member G.

The refractive indexes of the glass block 13a, the transparent member G, and the optical fiber 3 in the ferrule F are the same or substantially the same as each other.

As described above, the glass block 13a made of a material having the same or almost the same refractive index and the optical fiber 3 in the transparent member G and the ferrule F are brought into close contact with each other, whereby air enters between the joint surfaces. It is possible to prevent the occurrence of accidental reflection of light. In this way, by incorporating the antireflection structure, it is possible to obtain a higher performance optical transceiver module.

[0120]

According to the first aspect of the invention, the first light receiving means can receive the received signal light which has passed through the waveguide of the light emitting means. Further, since the light emitting means emits the transmission signal light in a wavelength band wider than the predetermined wavelength band used for transmission without resonating, it monitors other wavelength light in the predetermined wavelength band used for transmission in this wide wavelength band. Etc. can be used as a detection signal. In addition, since there is no resonance, fluctuations in output and wavelength can be reduced.

Further, since the other wavelength light demultiplexed by the demultiplexing means provided between the light input / output section and the light emitting means does not include the reflected return light from the surface of the optical component, the light emitting means. It is most suitable for detecting the output for stable and accurate output control.

Since the above-mentioned effects are obtained by the optical system arranged similarly to the conventional structure, it is not necessary to upsize the device.

According to the invention described in claim 2, the first
The received signal light of the first wavelength that has passed through the waveguide of the light emitting means can be received by the first light receiving means. Further, since the first light emitting means emits the transmission signal light having a wavelength band wider than the predetermined wavelength band including the first wavelength light used for transmission without resonating, it emits light other than the predetermined wavelength band in the wide wavelength band. By demultiplexing the wavelength light by the demultiplexing means, without affecting the output efficiency,
Further, it is possible to detect the optimum output signal to be used as the detection signal for the monitor, which is not affected by the reflected return light on the surface of the optical component or the like. The above-described effect can be obtained by the optical system arranged similarly to the conventional structure, and it is not necessary to upsize the device. Also, since the light emitting means does not resonate,
It is possible to reduce fluctuations in output and wavelength as compared with the resonance type. Further, by receiving and transmitting the second wavelength light from the optical input / output unit demultiplexed by the demultiplexing means by the third light receiving and second light emitting means, the two-way communication by the first wavelength light as well as the first wavelength light is performed. Two wavelength light can be transmitted and received.

According to the invention described in claim 3, the first
The received signal light of the first wavelength that has passed through the waveguide of the light emitting means can be received by the first light receiving means. Further, since the first light emitting means emits the transmission signal light having a wavelength band wider than the predetermined wavelength band including the first wavelength light used for transmission without resonating, it emits light other than the predetermined wavelength band in the wide wavelength band. By demultiplexing the wavelength light by the demultiplexing means, without affecting the output efficiency,
Furthermore, it is possible to detect an output signal that is optimal for use as a detection signal for a monitor that is not affected by the reflected return light on the surface of an optical component or the like. Further, the above-described effects can be obtained by the optical system arranged similarly to the conventional structure, and it is not necessary to upsize the device. Also, since the light emitting means does not resonate,
It is possible to reduce fluctuations in output and wavelength as compared with the resonance type. Further, by receiving or transmitting the second wavelength light from the optical input / output unit demultiplexed by the demultiplexing means by the third light receiving or second light emitting means, the two-way communication by the first wavelength light and the second wavelength light are performed. One-way reception or transmission of dual wavelength light is possible.

According to the optical transceiver module of the fourth aspect, the output control means for controlling the output of the light emitting means based on the detection value of the second light receiving means is provided. It is possible to obtain an accurate and stable transmission output of the optical transceiver module.

Further, according to the optical transceiver module of the fifth aspect, the correction means for correcting the optical signal received by the first light receiving means into the received signal light based on the detection value of the second light receiving means is provided. Thus, the optical transmission / reception module according to claim 1 or 2 can be an optical communication module capable of simultaneous bidirectional communication.

According to the sixth aspect of the invention, the second light receiving means can receive the signal light received from the light input / output portion through the waveguide of the light emitting means. As a result, the first light receiving means for reception can be provided at the same position as the light receiving element for monitoring, which is conventionally provided at the rear portion of the semiconductor laser. That is, since the same optical system as that of the conventional optical communication module can be used, the size of the device is not increased. Further, the output control means for controlling the light output of the light emitting means is performed based on the detection value of the second light receiving means for detecting the light obtained by branching a part of the transmission signal by the branching means. As a result, the second light receiving means detects the light on the output side of the transmission signal, so that only the output of the light emitting means can be detected without receiving the reflected return light from the surface of the optical component, and accurate and stable output control can be performed.

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing a schematic configuration of an optical transceiver module according to a first embodiment of the present invention.

FIG. 2 is an explanatory diagram showing a distribution of light intensity with respect to a wavelength of light demultiplexed by the demultiplexing means in each exemplary embodiment of the present invention.

FIG. 3 shows changes in signal intensity with respect to time in each of the embodiments of the present invention according to signal processing states (a), (b),
It is explanatory drawing demonstrated in each figure of (c).

FIG. 4 shows changes in signal strength with respect to time in each of the embodiments of the present invention according to signal processing states (e), (f),
It is explanatory drawing demonstrated in each figure of (g).

FIG. 5 is an explanatory diagram showing a schematic configuration of an optical transceiver module according to a second embodiment of the present invention.

FIG. 6 is an explanatory diagram showing a schematic configuration of an optical transceiver module according to a third embodiment of the present invention.

FIG. 7 is an explanatory diagram showing a schematic configuration of an optical transceiver module according to a fourth embodiment of the present invention.

FIG. 8 is an explanatory diagram showing a schematic configuration of an optical transceiver module according to a fifth embodiment of the present invention.

FIG. 9 is an explanatory diagram showing a schematic configuration of an optical transceiver module according to a sixth embodiment of the present invention.

FIG. 10 is an explanatory diagram showing a schematic configuration of a main part of an optical transceiver module according to a seventh embodiment of the present invention.

FIG. 11 is an explanatory diagram showing a schematic configuration of a conventional optical transceiver module.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Optical transmission / reception module 3 Optical fiber (optical input / output part) 11 SLD (light emitting means) 11a Waveguide 13 Interference filter (demultiplexing means) 17 APC (output control means) 22 Correction circuit (correction means) PD1 1st photodiode ( First light receiving means) PD2 Second photodiode (second light receiving means)

Claims (6)

[Claims] 1. A transmission signal light emitted toward an optical input / output unit for inputting / outputting an optical signal is emitted without resonance in a predetermined wavelength band, and a received signal light from the optical input / output unit is guided. Light emitting means having a waveguide, first light receiving means for receiving and photoelectrically converting the received signal light transmitted through the waveguide of the light emitting means, and wavelength light within a predetermined wavelength band between the optical input / output part and the light emitting means. And a second light receiving unit for detecting and photoelectrically converting the other wavelength light demultiplexed by the demultiplexing unit, and an optical transmission / reception module. 2. An optical input / output unit for inputting / outputting an optical signal for transmitting / receiving a first wavelength and transmitting and / or receiving a second wavelength different from the first wavelength. 1
First light emitting means that emits light including a transmission signal light of a wavelength in a wavelength band wider than a predetermined wavelength band without resonating, and has a waveguide that guides a reception signal of the first wavelength; Section and the first light emitting means, the demultiplexing means for demultiplexing the optical signal within the predetermined wavelength band including the first wavelength and the other wavelength light including the second wavelength, and the waveguide of the first light emitting means. The first light receiving means for receiving and photoelectrically converting the received signal light of the first wavelength, and the other wavelength light not including the first wavelength demultiplexed from the transmission signal light by the demultiplexing means are detected and photoelectrically converted. A second light receiving means, a third light receiving means for receiving the second wavelength demultiplexed from the received signal light by the demultiplexing means, and a second light emitting means for emitting the second wavelength light toward the light input / output unit through the demultiplexing means. An optical transceiver module comprising: a light emitting means. 3. An optical input / output unit for inputting / outputting an optical signal for transmitting / receiving a first wavelength and transmitting and / or receiving a second wavelength different from the first wavelength. 1
First light emitting means that emits light including a transmission signal light of a wavelength in a wavelength band wider than a predetermined wavelength band without resonating, and has a waveguide that guides a reception signal of the first wavelength; Section and the first light emitting means, the demultiplexing means for demultiplexing the optical signal within the predetermined wavelength band including the first wavelength and the other wavelength light including the second wavelength, and the waveguide of the first light emitting means. The first light receiving means for receiving and photoelectrically converting the received signal light of the first wavelength, and the other wavelength light not including the first wavelength demultiplexed from the transmission signal light by the demultiplexing means are detected and photoelectrically converted. The second light receiving means and the second light emitting means for emitting the second wavelength toward the light input / output section through the third light receiving means or the demultiplexing means for receiving the second wavelength demultiplexed from the received signal light by the demultiplexing means. An optical transmitter / receiver module comprising: 4. The optical transceiver module according to claim 1, 2 or 3, further comprising output control means for controlling the output of the light emitting means based on the detection value of the second light receiving means. . 5. A correction means for correcting a signal received by the first light receiving means into a received signal based on a detection value of the second light receiving means.
Alternatively, the optical transceiver module according to claim 4. 6. A light emitting means including a laser oscillator for emitting a transmission signal light to be emitted toward an optical input / output portion for inputting / outputting an optical signal, and a transmission signal between the optical input / output portion and the light emitting means. Splitting means for splitting a part of the light, first light receiving means for receiving and photoelectrically converting the received signal light from the light input / output part that has passed through the light emitting means, and part of the transmission signal light split by the splitting means Second light receiving means for detecting and photoelectrically converting light, output control means for controlling the output of the light emitting means based on the detection value of the second light receiving means, and timing for transmission / reception between the light emitting means and the first light receiving means An optical transceiver module comprising time division control means.