JP4670364B2 - Optical communication device - Google Patents

Description

  The present invention relates to an optical communication device, and more particularly, to a distributed optical signal transmission body connected to a plurality of second devices through different optical fibers, respectively, and to the plurality of second devices. The present invention relates to an optical communication apparatus capable of transmitting information to each by optical communication.

  Conventionally, a layered waveguide that diffuses and propagates incident signal light is formed by forming a plurality of signal light input / output portions that are responsible for input / output of signal light, and the incident optical signal is distributed to a plurality of distribution destinations. Distributable distribution type optical signal transmission bodies (hereinafter also referred to as optical sheet buses) and an optical communication system including the distribution type optical signal transmission bodies have been proposed (see Patent Documents 1 to 6). reference).

  When distributing highly directional optical signals such as laser light, the optical signal was previously converted into electrical signals and distributed, and then the distributed electrical signals are sent to a plurality of light sources provided corresponding to each distribution destination. Although a complicated configuration such as transmitting an optical signal to each distribution destination by an element was required, it becomes possible to directly distribute an optical signal with strong directivity by using the above-described distribution type optical signal transmitter, The configuration of the optical communication system can be simplified.

In addition, the distribution type optical signal transmission body can easily insert and remove the optical fiber that transmits the optical signal in the same manner as the signal line of the electric signal is inserted and removed by the connector, and the construction of the optical communication system and the change of the configuration can be performed. It has the advantage of being easy.
Japanese Patent Laid-Open No. 9-270751 Japanese Patent Laid-Open No. 9-270752 Japanese Patent Laid-Open No. 10-65625 Japanese Patent Laid-Open No. 11-39069 JP-A-11-39251 JP-A-11-205246

  By the way, when the above-mentioned distributed optical signal transmission body is used in an optical communication system, the construction and configuration change of the optical communication system can be easily performed, but the light from the light emitting element provided in the optical signal transmission source device can be used. There is a possibility that the optical attenuation of the optical signal in each of a plurality of optical transmission paths reaching each light receiving element provided in each of a plurality of devices as signal transmission destinations is greatly different (in particular, as an optical fiber, the optical attenuation is In the case of using POF (Plastic Optical Fiber), which is frequently used for transmission of optical signals over a short distance, the possibility is high).

  And depending on the light attenuation amount of the optical signal in each optical transmission line and the light emission intensity of the light emitting element provided in the optical signal transmission source device, in a specific device among a plurality of devices as the optical signal transmission destination, There is a problem that a situation in which an optical signal transmitted from an optical signal transmission source device cannot be received by the specific device may occur because the amount of light received by the light receiving element deviates from the light receiving range. .

  In order to solve the above problem, it is conceivable that all devices as optical signal communication destinations emit light with a light emission intensity that can reliably receive an optical signal, but the light emitting element is from an LD (laser diode) or the like. As the light emission intensity increases, the lifetime is shortened and the amount of heat generated during light emission is increased. Therefore, as described above, the light emitting element has a light emission intensity with which all devices can reliably receive an optical signal. When the light is emitted, the life of the light emitting element is shortened, and it is necessary to frequently replace the light emitting element. In addition, a facility for cooling the light emitting element is required, which causes another problem that the power consumption is increased.

  On the other hand, in order to solve the above problem, it is conceivable to set a minimum light emission intensity that can be received for each device of the communication destination, and cause the light emitting element to emit light with the set light emission intensity. Is easily influenced by environmental conditions such as environmental temperature and environmental humidity, and a problem arises in that the light emission intensity decreases due to a change in the environmental conditions, and communication temporarily becomes impossible.

  The present invention has been made in consideration of the above-described facts. The object of the present invention is to provide a plurality of light sources through a distributed optical signal transmission body even when the light emission intensity of the light emitting element is reduced due to a change in environmental conditions. An object of the present invention is to provide an optical communication apparatus capable of reliably performing optical communication with an apparatus.

To achieve the above object, an optical communication apparatus of the present invention includes a light emitting element that transmits an optical signal and a light receiving element that receives an optical signal, and is connected to a plurality of devices via a distributed optical signal transmitter, An optical communication device capable of transmitting and receiving optical signals to and from a plurality of devices, and communicates from a light emitting element driving unit that drives the light emitting element based on light emission intensity control information, and an optical signal received by the light receiving element A reception information acquisition unit that acquires reception information including a reception state of the device, a measurement unit that measures an environmental temperature and an environmental humidity where the light emitting element is placed, a heating unit and a cooling unit that adjust the environmental temperature and the environmental humidity . and driving at least one, and correction means for correcting at least one of the environmental temperature light emitting element is placed and the environmental humidity, each connected to a plurality of devices, the set value of the emission intensity of the light emitting element, the Light emission Wherein the environmental temperature or humidity measured by the measuring means, the received information acquired by the reception information acquiring unit and the received information acquisition when light was emitted at a set value of the emission intensity when emitted in every set value Storage means stored as light emission intensity control information including optimum light emission intensity information for causing the light emitting element to emit light at an optimum light emission intensity, and driving the light emitting element based on the light emission intensity control information When the light emitting element is driven by a unit to transmit an optical signal for intensity detection including optimum light emission intensity information for each of the plurality of devices, and reception information cannot be acquired by the reception information acquisition unit, an environmental temperature and environment When at least one of the humidity exceeds the upper limit value, the cooling means is driven to cool the light emitting element, and when at least one of the environmental temperature and the environmental humidity falls below the lower limit value, Again transmits an optical signal for the intensity detected based on the emission intensity control information after correcting at least one of environmental temperature and environmental humidity by the correction means so that the light emitting element heating means is driven to heat or the optical signal for intensity detection including optimum luminous intensity information after the change by changing the set value of the luminous intensity transmitted back in response to the environmental temperature or humidity measured by the measuring means, the received And a control unit that controls to detect new emission intensity control information based on the acquired reception information and store it in the storage unit when the information acquisition unit can acquire the reception information.

  In the optical communication device of the present invention, when detecting the optimum light emission intensity of the light emitting element of the transmission side device for keeping the amount of light received by the light receiving element of the reception side device within an allowable range, The current environmental condition is corrected by the correcting means so as to conform to the measured environmental condition, or the emission intensity of the light emitting element of the transmitting apparatus is changed so as to conform to the current environmental condition, and The light emitting element emits light. And the optimal light emission intensity at the time of transmitting information by optical communication to a receiving side apparatus is detected by receiving the light reception state information showing the light reception state by the light receiving element of a receiving side apparatus from a receiving side apparatus. Thereby, even when the light emission intensity of the light emitting element of the transmission side device is reduced due to a change in environmental conditions, optical communication with the reception side device can be reliably performed via the distributed optical signal transmitter.

  As described above, according to the present invention, even when the light emission intensity of a light emitting element is reduced due to a change in environmental conditions, it is possible to reliably perform optical communication with a plurality of devices via a distributed optical signal transmission body. There is an effect that.

Hereinafter, an example of an embodiment of the present invention will be described in detail with reference to the drawings.
[Configuration of electronic equipment]
FIG. 1 shows an electronic apparatus 10 according to the present embodiment. The electronic device 10 includes a plurality of electronic circuits 12A, 12B, 12C, and 12D. Of the electronic circuits 12A to 12D, the electronic circuit 12A functions as a master that controls the operation of the other electronic circuits 12B to 12D, and the electronic circuits 12B to 12D function as slaves that operate under the control of the electronic circuit 12A.

  Although any device can be applied as the electronic device 10, each color component is received by receiving image data via a network such as a LAN and performing image processing such as screen processing based on the received image data. (For example, C (cyan), M (magenta), Y (yellow), K (black), S (special color), etc.) exposure image data is generated, and each color component is generated based on the generated exposure image data. An electrostatic latent image of each color component is formed by controlling image exposure by a ROS (Raster Output Scanner) provided in the image, and the formed electrostatic latent image of each color component is developed with each color component developer and superimposed. Thus, it is possible to apply a full color printer having a configuration in which a full color toner image is formed and the formed full color toner image is transferred and fixed onto a recording sheet.

  In this case, as the electronic circuits 12B to 12D functioning as slaves, an image processing circuit for controlling generation of image data for exposure of each color component and image exposure by ROS is used. As an electronic circuit 12A functioning as a master, each image processing is performed. A control circuit that controls the operation of the circuit (for example, a control circuit including a peripheral device such as a CPU and a memory) can be applied.

  In this embodiment, communication between the electronic circuit 12A and the electronic circuits 12B to 12D is performed by optical communication, and optical communication between these electronic circuits is performed between the electronic circuit 12A and the electronic circuits 12B to 12D. An optical communication system 14 to be realized is provided. The optical communication system 14 includes optical communication interface (I / F) units 16A to 16D connected to the individual electronic circuits 12A to 12D.

  The optical communication I / F units 16A to 16D are mounted on the same substrate as the connected electronic circuits 12A to 12D, respectively. The optical communication I / F units 16A to 16D have substantially the same configuration, and a plurality of (for example, five) LD (laser diode) LD arrays 18 arranged in a line and a plurality of (for example, five) There are provided a PD array 20 in which a plurality of PDs (light detectors) are arranged in a line, and an optical communication control unit 22 connected to the electronic circuit 12, the LD array 18 and the PD array 20, respectively.

  In the vicinity of the LD array 18, a humidity sensor 80 that measures the environmental humidity of the LD array 18, a temperature sensor 82 that measures the environmental temperature of the LD array 18, an air cooling fan 84 for cooling the LD array 18, and the LD array 18. A heater 86 for heating the heater is disposed.

  Each of the LD array 18 and the PD array 20 of each optical communication I / F unit 16 is configured so that the optical connector 24 can be freely attached and detached, and the optical connector 24 connected to the LD array 18 of the optical communication I / F unit 16A. One end of the first optical fiber 26 is attached, and one end of the first optical fiber 28 is attached to the optical connector 24 attached to the PD array 20, and is connected to the LD array 18 of the optical communication I / F unit 16B. One end of the second optical fiber 36 is attached to the optical connector 24, and one end of the second optical fiber 30 is attached to the optical connector 24 attached to the PD array 20.

  Similarly, one end of the second optical fiber 38 is connected to the optical connector 24 connected to the LD array 18 of the optical communication I / F unit 16C, and the second optical fiber 32 is connected to the optical connector 24 connected to the PD array 20. One end of the second optical fiber 40 is connected to the optical connector 24 connected to the LD array 18 of the optical communication I / F unit 16D, and the second end is connected to the optical connector 24 connected to the PD array 20. One end of the optical fiber 34 is attached.

  The first optical fibers 26 and 28 and the second optical fibers 30, 32, 34, 36, 38 and 40 are optical fibers made of synthetic resin called POF (Plastic Optical Fiber) (the core material is acrylic, and the cladding covers the core material) An optical fiber whose material is made of fluororesin is bundled by the same number (for example, five) as the number of LDs in the LD array 18 and the number of PDs in the PD array 20.

  As shown in FIG. 2, optical connectors 24 are respectively attached to the other ends of the first optical fiber 26 and the second optical fibers 30, 32, and 34, and these optical connectors 24 are connected to the optical sheet bus 42A. ing. Although not shown in detail, the optical connectors 24 are respectively attached to the other ends of the first optical fiber 28 and the second optical fibers 36, 38, 40, and these optical connectors 24 are respectively connected to the optical sheet bus 42B. It is connected. The optical sheet buses 42A and 42B correspond to the distribution type optical signal transmission body according to the present invention.

  The optical sheet buses 42A and 42B are configured by embedding a waveguide member 44 shown in FIG. 3 in the same number (for example, five) as the number of optical fibers in a synthetic resin base member. The waveguide member 44 is made of a material having a high light transmittance and a refractive index higher than that of a clad layer to be described later (for example, polymethylmethacrylate). The waveguide member 44 has an elongated rectangular shape as a whole, and the width dimension changes in a stepped manner. The stepped portions 46A and 46B are formed at two locations in the middle portion.

  Inclinations that are inclined at an angle of 45 ° with respect to the longitudinal direction and the vertical direction of the waveguide member 44 (vertical direction in FIG. 3) at both ends of the waveguide member 44 and the stepped portions 46A and 46B. Surfaces 44A to 44D are respectively formed. The inclined surfaces 44A to 44D function as signal light incident / exit portions.

  The waveguide member 44 is embedded so that portions of the upper surface of the waveguide member 44 corresponding to the individual inclined surfaces 44 </ b> A to 44 </ b> D are exposed from the upper surface of the base member. Of these, the base member is connected to face the exposed portion. The waveguide member 44 is covered with a clad layer whose outer surface other than the portion exposed from the upper surface of the base member is made of a material having a refractive index lower than that of the material constituting the waveguide member 44 (for example, a fluorine polymer). Has been.

  In the optical sheet bus 42A, the optical connector 24 to which the first optical fiber 26 is attached has a base so as to face an exposed portion corresponding to the inclined surface 44A formed in the portion of the waveguide member 44 having the largest width dimension. The optical connector 24 connected to the member and having the second optical fibers 30, 32, and 34 attached thereto is connected to the base member so as to face the exposed portion corresponding to the inclined surfaces 44B to 44D.

  Since the first optical fiber 26 is connected to the LD array 18 of the optical communication I / F unit 16A via the optical connector 24, when the LD array 18 of the optical communication I / F unit 16A emits light, The signal light (laser light) emitted from the LD is transmitted through the first optical fiber 26, is incident on the waveguide member 44, is reflected by the inclined surface 44A, and is confined in the waveguide member 44. It diffuses and propagates in the waveguide member 44.

  As shown in FIG. 3A, the light is emitted from the waveguide member 44 by being reflected by the inclined surfaces 44 </ b> B to 44 </ b> D and transmitted through the optical connector 24 through the second optical fibers 30, 32, and 34. The light is received by the PD arrays 20 of the optical communication I / F units 16B to 16D.

  In the optical sheet bus 42B, the optical connector 24 to which the first optical fiber 28 is attached is connected to the base member so as to face the exposed portion corresponding to the inclined surface 44A, and the second optical fibers 36, 38, and 40 are connected. The attached optical connector 24 is connected to the base member so as to face the exposed portion corresponding to the inclined surfaces 44B to 44D.

  Since the second optical fibers 36, 38, and 40 are connected to the LD array 18 of the optical communication I / F units 16B to 16D via the optical connector 24, any one of the LDs of the optical communication I / F units 16B to 16D. When the array 18 emits light, the signal light (laser light) emitted from the individual LDs of the LD array 18 is transmitted through one of the second optical fibers 36, 38, and 40 and is incident on the waveguide member 44. It is diffused and propagated in the waveguide member 44 in a state of being confined in the waveguide member 44 by being reflected by any of the surfaces 44B to 44D.

  Then, as shown in FIG. 3B, the light is emitted from the waveguide member 44 by being reflected by the inclined surface 44A, is transmitted through the first optical fiber 28 via the optical connector 24, and the optical communication I / F. Light is received by the PD array 20 of the section 16A.

  As described above, the LD array 18 of the optical communication I / F unit 16A includes the optical communication I / F units 16B to 16D via the first optical fiber 26, the optical sheet bus 42A, and the second optical fibers 30, 32, and 34. The LD array 18 of each of the optical communication I / F units 16B to 16D includes the second optical fibers 36, 38, and 40, the optical sheet bus 42B, and the first optical fiber 28. Via the PD array 20 of the optical communication I / F unit 16A. In this embodiment, the distance of the optical transmission path between the optical communication I / F unit 16A and the optical communication I / F units 16B to 16D is set to about 5 m.

  Next, the configuration of the optical communication control unit 22 provided in each of the optical communication I / F units 16A to 16D will be described with reference to FIG. The optical communication control unit 22 includes an electronic circuit I / F unit 50 that is connected to the electronic circuit 12 and manages communication with the electronic circuit 12. The electronic circuit I / F unit 50 receives information to be transmitted to the other electronic circuit 12 from the electronic circuit 12 and transmits information received from the other electronic circuit 12 to the electronic circuit 12.

  A transmission control unit 52 is connected to the electronic circuit I / F unit 50, and information received by the electronic circuit I / F unit 50 from the electronic circuit 12 (transmission information to be transmitted to other electronic circuits 12) is transmission controlled. Is output to the unit 52. The transmission control unit 52 includes a non-volatile NVM memory 54 formed of a flash memory or the like, and an optimum emission intensity table (details will be described later) is stored in the NVM memory 54.

  In the present embodiment, the NVM memory 54 of the optical communication I / F unit 16A has the optical communication I / F unit 16 (16B to 16B) connected to the individual electronic circuits 12 (12B to 12D) functioning as slaves. 16D) and an ID set in advance for the optical communication I / F unit 16 (16B to 16D) are stored in advance, and the NVM memory 54 of the optical communication I / F units 16B to 16D stores the ID. The own ID and an ID set in advance for the optical communication I / F unit 16A are stored in advance.

  In the above information, for example, the number of optical communication I / F units 16 connected to the electronic circuit 12 functioning as a slave has increased or decreased due to the configuration change of the electronic device 10 such as the addition of the electronic circuit 12 functioning as a slave. In some cases, it is rewritten by an operator or the like.

  An 8B / 10B encoder 56 is connected to the transmission controller 52, and transmission information is output from the transmission controller 52 to the 8B / 10B encoder 56 byte by byte. Each PD of the PD array 20 has a characteristic that the response decreases when the state where light is not received continues.

  The optical communication system 14 according to the present embodiment transmits transmission information serially by an optical signal, but normal data is data in which all bits are 0 or 1 (the LD emits light while transmitting all bits of data). Data may not be included), and while such data is being transmitted serially, the PD on the receiving side may become inactive and the response may be reduced.

  For this reason, the 8B / 10B encoder 56 is configured so that the ratio of 0 bits and 1 bits included in all bits of the transmission information input by 1 byte (8 bits) from the transmission control unit 52 does not fall below a certain value. The 8-bit transmission information is converted into 10-bit transmission information in accordance with the conversion conditions set in advance. Note that a plurality of 8B / 10B encoders 56 are actually provided, and conversion from 8-bit transmission information to 10-bit transmission information is performed in parallel by the individual 8B / 10B encoders 56.

  The 8B / 10B encoder 56 is connected to the LD drive unit 62 via a P / S (parallel / serial) conversion unit 60, and the 10-bit transmission information converted by the 8B / 10B encoder 56 is converted to P / S. After being input to the unit 60 and converted into serial data, it is input to the LD driving unit 62.

  Further, an ECC (Error-Correcting Code) generation unit 58 is connected to the 8B / 10B encoder 56, and the 10-bit transmission information output from the 8B / 10B encoder 56 is also input to the ECC generation unit 58. An error correction code for error correction is generated by the generation unit 58. The ECC generation unit 58 is also connected to the LD drive unit 62 via the P / S conversion unit 60, and the error correction code generated by the ECC generation unit 58 is converted into serial data by the P / S conversion unit 60. After that, the signal is input to the LD driving unit 62.

  Then, the LD drive unit 62 responds to the transmission information input from the 8B / 10B encoder 56 via the P / S conversion unit 60 and the error correction code input from the ECC generation unit 58 via the P / S conversion unit 60. The transmission information is transmitted as an optical signal by controlling turning on / off of each LD in the LD array 18.

  The LD driving unit 62 is connected to the transmission control unit 52, and a clock signal and light emission intensity control information are input from the transmission control unit 52. A specific LD in the LD array 18 is used for transmitting a clock signal, and the LD driving unit 62 controls turning on / off of the specific LD according to the input clock signal. The LD driving unit 62 can control the light emission intensity of each LD of the LD array 18 and controls the light emission intensity of each LD according to the input light intensity control information.

  The humidity sensor 80 and the temperature sensor 82 are connected to the transmission control unit 52, and sensor signals output from the humidity sensor 80 and the temperature sensor 82 are respectively input to the transmission control unit 52. In addition, the air cooling fan 84 and the heater 86 are connected to the transmission control unit 52, and a drive signal output from the transmission control unit 52 is input to each of the air cooling fan 84 and the heater 86.

  On the other hand, a signal processing unit 64 is connected to the PD array 20, and each PD in the PD array 20 receives (receives) an optical signal, so that an output signal from each PD is amplified by the signal processing unit 64. , Demodulated into digital reception information and output. The signal processing unit 64 is connected to the error correction unit 70 via an S / P (serial / parallel) conversion unit 66, and serial reception information output from the signal processing unit 64 is parallelized by the S / P conversion unit 66. After being converted into the received information, it is input to the error correction unit 70.

  The signal processing unit 64 is connected to the error detection unit 68 via the S / P conversion unit 66. The error detection unit 68 generates an error (error) such as garbled bits in the reception information body based on the error collection code included in the parallel reception information input from the signal processing unit 64 via the S / P conversion unit 66. Verify whether or not. The error correction unit 70 is connected to the error detection unit 68, and performs error correction on the reception information body when the error detection unit 68 detects that an error has occurred in the reception information body.

  The error correction unit 70 is connected to the reception control unit 74 via the 8B / 10B decoder 72, and the reception information (main body) output from the error correction unit 70 after error correction is 10 bits by the 8B / 10B decoder 72. The data is converted into normal 8-bit data in units and input to the reception control unit 74. The signal processing unit 64 is connected to the reception control unit 74, and among the received optical signals, the clock signal is directly input to the reception control unit 74 and used to synchronize with the optical signal transmission side.

  The reception control unit 74 is connected to each of the electronic circuit I / F unit 50 and the transmission control unit 52, and outputs the received reception information to the transmission control unit 52 and also electronically via the electronic circuit I / F unit 50. Output to the circuit 12. The signal processing unit 64 is also connected to the transmission control unit 52, and outputs received light amount information representing the received light amount of the optical signal to the transmission control unit 52 at the time of optical signal reception (light reception).

  The optical communication I / F unit 16A corresponds to the optical communication device and the first device according to the present invention, and each LD of the LD array 18 of the optical communication I / F unit 16A corresponds to the first light emitting element according to the present invention. In addition, each PD in the PD array 20 of the optical communication I / F unit 16A corresponds to the first light receiving element according to the present invention. The optical communication I / F units 16B to 16D correspond to the optical communication device and the second device according to the present invention, and each LD of the LD array 18 of the optical communication I / F units 16B to 16D is related to the present invention. Each PD of the PD array 20 of the optical communication I / F units 16B to 16D corresponds to the second light receiving element according to the present invention.

[Operation of electronic equipment]
Next, the operation of electronic device 10 according to the present embodiment will be described.

  In the present embodiment, when the electronic device 10 is turned on, the optical communication control unit 22 (the transmission control unit 52) of the optical communication I / F unit 16A connected to the electronic circuit 12A functioning as a master functions as a slave. The optimum light emission intensity of each LD of the LD array 18 of the optical communication I / F unit 16A when information is transmitted to the optical communication I / F unit 16 connected to each electronic circuit 12 is determined for each optical communication I / F. Optimal emission intensity detection processing (FIG. 5A) for detecting each of the units 16B to 16C is executed.

  When the execution of the optimum emission intensity detection process is completed, the transmission control unit 52 starts measuring the elapsed time from the end of the execution, and also detects the optimum emission intensity even when a predetermined time or more has elapsed since the previous execution. Process.

  Hereinafter, the optical communication I / F unit 16A is simply referred to as a “master”. The optimum emission intensity detection process executed by the master is a process corresponding to the first detection means according to the present invention, and the transmission control unit 52 of the master optical communication control unit 22 executes this optimum emission intensity detection process. Thus, it functions as the first detecting means according to the present invention.

(Optimum emission intensity detection process executed by the master)
Next, with reference to FIG. 5, the processing routine of the optimum light emission intensity detection process at the master will be described.

  First, in step 100, by referring to the NVM memory 54, the number of optical communication I / F units 16 (hereinafter simply referred to as “slaves”) connected to the individual electronic circuits 12 functioning as slaves and the individual numbers are individually determined. Recognizes the ID set in advance in the slave. In the next step 102, a slave to be processed (hereinafter referred to as “slave n” for convenience) is determined.

  In step 104, it is determined whether or not the optimum emission intensity of the master LD array 18 for the slave n is registered in the optimum emission intensity table of the NVM memory 54. If the determination is negative, it can be determined that the optimum light emission intensity of the master LD array 18 for the slave n has not been detected, for example, because the slave n is newly added this time. , The initial setting process is performed. If the determination in step 104 is affirmative, the process proceeds to step 108, and the normal setting process is performed.

  In the next step 110, information for notifying the above-mentioned optimum emission intensity to the slave n is generated, and the ID of the slave n as the transmission destination ID and the ID of itself (master) as the transmission source ID are generated in the generated information. In addition, it transmits by optical communication. In the optimum light emission intensity detection process executed by the master, in the next step 112, it is determined whether or not the processes after step 102 described above have been performed for all the slaves.

  If the determination is affirmative, the processing routine is terminated. If the determination is negative, the processing returns to step 102, and the processing of step 102 is repeated with a new slave as a processing target. As a result, the optimum emission intensity of the master LD array 18 is detected for all slaves, and the detected optimum emission intensity is registered in the optimum emission intensity table of the NVM memory 54, and is also stored in the corresponding slave n. You will be notified.

  Next, the processing routine of the initial setting process shown in FIG. 6 will be described.

  In the initial setting process, after setting a predetermined value as the initial value and change range of the light emission intensity of each LD of the LD array 18 for detecting the optimum light emission intensity of the master LD array 18 for the slave n in step 200, step 202 is performed. Migrate to In the next step 202, in the intensity detection information used when each LD of the LD array 18 emits light for detecting the optimum light emission intensity, the ID of the slave n as the transmission destination ID and the own (master) as the transmission source ID. Each ID is added, and emission intensity information indicating the emission intensity (initial value set above) of each LD of the LD array 18 is added.

  In step 204, emission intensity control information for causing each LD of the LD array 18 to emit light with the set emission intensity is output to the LD drive unit 62, and the intensity detection is performed by adding the slave n and master IDs and the emission intensity information. The use information (transmission information) is output to the LD drive unit 62 via the 8B / 10B encoder 56, the ECC generation unit 58, and the P / S conversion unit 60.

  Thereby, each LD of the master LD array 18 is turned on / off according to the transmission information so that the light emission intensity at the time of lighting (light emission) matches the set light emission intensity. The modulated optical signal is emitted from the master LD array 18 and transmitted through the first optical fiber 26, the optical sheet bus 42A, and the second optical fibers 30, 32, and 34, and then each slave (optical communication I / F unit 16B to 16B). 16D) is received by the PD array 20 respectively.

  By adding the slave ID as the transmission destination ID to the information transmitted to the slave, the information transmitted to the specific slave is misrecognized as information addressed to the own device by a slave other than the specific slave. Can be prevented.

  On the other hand, in each slave, when the PD array 20 receives an optical signal and the amount of received light is within the allowable range of each PD of the PD array 20, the received optical signal is demodulated as reception information, and S The data is input to the reception control unit 74 via the / P conversion unit 66, the error detection unit 68, the error correction unit 70, and the 8B / 10B decoder 72. Then, when the reception information is input from the reception control unit 74 to the transmission control unit 52, an optical signal reception process (see FIG. 9) described later is executed in the transmission control unit 52.

  In the next step 206, it is determined whether a light reception state notification is received from the slave n. When determination is denied, it transfers to step 208, and it is determined whether predetermined time passed since transmitting the optical signal. If the determination is negative, the process returns to step 206, and steps 206 and 208 are repeated until either determination is positive.

  Here, when the received light amount of the optical signal in the slave n is outside the allowable range of each PD of the PD array 20 (when the received light amount is insufficient), the determination in step 208 is affirmed and the process proceeds to step 210. The process returns to step 202 after setting the emission intensity setting value to be increased by a predetermined amount. Thereby, each LD of the LD array 18 is turned on / off again according to the transmission information so that the light emission intensity at the time of lighting (light emission) is increased by a predetermined amount, so that the light modulated according to the same transmission information The signal is sent again to each slave.

  Further, the process of step 210 described above is executed every time the determination of step 208 is affirmed. Therefore, if the amount of light received by the slave n is insufficient, the light emission intensity of each LD of the master LD array 18 is increased by a predetermined amount until the amount of light received by the slave n falls within the allowable range. The transmission of the optical signal is repeated while increasing.

  On the other hand, when the light reception state information to which the light emission intensity information is added is received from the slave n, the determination in step 206 is affirmed and the process proceeds to step 212, and the received light reception state information is referred to to add to the light reception state information. It is determined whether or not the light emission intensity represented by the emitted light intensity information is the optimum light emission intensity of each LD of the LD array 18 when transmitting information to the slave n.

  As this optimum light emission intensity, for example, a light emission intensity that is in an optimal state in which the light reception amount of each PD of the slave n PD array 20 matches the lower limit value of the allowable range of the light reception amount can be applied. By emitting light with the optimum light emission intensity, the life of the master LD array 18 can be maximized, and the amount of heat generation can be suppressed to the necessary minimum.

  If the received light amount indicated by the received light reception state information is different from the light reception amount corresponding to the optimum state, the determination in step 212 is negative and the process proceeds to step 214, which is notified by the light reception state information. After changing the light emission intensity according to the light receiving state of each PD in the slave n PD array 20, the process returns to step 202.

  Thereby, each LD of the LD array 18 is turned on / off again according to the same information as the previous time so that the light emission intensity at the time of lighting (light emission) matches the light emission intensity after the change setting, and according to the same information as the previous time. The modulated optical signal is transmitted again to the slave n at a light emission intensity different from the previous time. Therefore, when the received light amount of the optical signal in the slave n is different from the received light amount corresponding to the optimum state, the light receiving amount of the optical signal in the slave n is set to the optimum state so that the PD array 20 of the slave n The transmission of the optical signal is repeated while changing the light emission intensity of each LD of the master LD array 18 according to the light receiving state of each PD.

  When the received light amount of each PD in the PD array 20 of the slave n matches the received light amount corresponding to the optimum state, the determination in step 212 is affirmed and the process proceeds to step 216. In step 216, sensor signals are taken from the humidity sensor 80 and the temperature sensor 82, and the current emission intensity (the emission intensity represented by the emission intensity information added to the last received light reception state information) is set as the master LD for the slave n. The optimum light emission intensity of the array 18 is registered in the optimum light emission intensity table of the NVM memory 54 in association with the current environmental temperature, environmental humidity, and ID of the slave n. Thus, the master NVM memory 54 corresponds to the first storage means according to the present invention.

  Further, as described above, the emission intensity information is added to the intensity detection information transmitted to the slave n to be processed, and the optimum emission intensity is based on the emission intensity information added to the light reception state information received from the slave n. By executing the process of recognizing (the light emission intensity of the master LD array 18 when the amount of light received by the slave n reaches the optimum state), the optimum light emission intensity can be reliably recognized.

  Next, the processing routine of the normal setting process shown in FIG. 7 will be described.

  In the normal setting process, in step 300, the optimum emission intensity of the master LD array 18 for the slave n detected in the previous optimum emission intensity detection process is read from the optimum emission intensity table, and in the next step 302, the optimum detection detected this time. On the assumption that the emission intensity is the same as or close to the read optimum emission intensity, the initial value and the change range of the emission intensity of each LD of the LD array 18 are set based on the read optimum emission intensity.

  When the optimum emission intensity of the master LD array 18 for the slave n detected in the previous optimum emission intensity detection process is registered in the optimum emission intensity table, the optimum emission intensity detected this time is registered in the optimum emission intensity table. There is a high possibility that the value is the same as or close to the optimum emission intensity.

  For example, the change range of the emission intensity is set to a range that is centered on the read optimum emission intensity and narrower than usual, and the initial value of the emission intensity is set to a value corresponding to the upper limit or lower limit of the set change range. Thereby, the time required for the optimum light emission intensity detection process can be shortened.

  In the next step 304, the slave n ID is added as the transmission destination ID and the own (master) ID is added as the transmission source ID to the intensity detection information, and the light emission representing the emission intensity of each LD of the LD array 18 is added. Add strength information. In step 306, light emission intensity control information for causing each LD of the LD array 18 to emit light with the set light emission intensity is output to the LD driving unit 62.

  In the next step 308, it is determined whether or not a light reception state notification is received from the slave n. If the determination is negative, the routine proceeds to step 310, where an environmental correction process for driving the air cooling fan 84 and the heater 86 to correct the current environmental condition to an environmental condition capable of emitting light is executed. Here, when the environmental condition is not corrected, a flag is set as described later.

  In the next step 312, it is determined whether or not the flag is set. If the flag is set, the determination in step 312 is affirmed and the routine proceeds to step 318, where the set value of the emission intensity is increased by a predetermined amount. After setting, return to Step 304. Thereby, each LD of the LD array 18 is turned on / off again according to the transmission information so that the light emission intensity at the time of lighting (light emission) is increased by a predetermined amount, so that the light modulated according to the same transmission information The signal is sent again to each slave.

  If the flag is not set, it is determined in step 314 whether a light reception state notification is received from slave n. When determination is denied, it transfers to step 316, and it is determined whether predetermined time passed after transmitting an optical signal. If the determination is negative, the process returns to step 314, and steps 314 and 316 are repeated until either determination is positive.

  The determination in step 316 is affirmed, and the process proceeds to step 318. After the emission intensity setting value is increased by a predetermined amount, the process returns to step 304. Thereby, each LD of the LD array 18 is turned on / off again according to the transmission information so that the light emission intensity at the time of lighting (light emission) is increased by a predetermined amount, so that the light modulated according to the same transmission information The signal is sent again to each slave.

  On the other hand, when the light reception state information to which the light emission intensity information is added is received from the slave n, the determination in step 308 or step 314 is affirmed, and the process proceeds to step 320. It is determined whether the light emission intensity represented by the light emission intensity information added to the information is the optimum light emission intensity of each LD of the LD array 18 when transmitting information to the slave n. If the received light amount represented by the received light reception state information is different from the light reception amount corresponding to the above-mentioned optimum state, the determination in step 320 is negative, the process proceeds to step 322, and the slave notified by the light reception state information After changing the light emission intensity according to the light receiving state of each PD in the n PD arrays 20, the process returns to step 304.

  When the received light amount of each PD in the PD array 20 of the slave n matches the received light amount corresponding to the optimum state, the determination in step 320 is affirmed and the process proceeds to step 324. In step 324, sensor signals are captured from the humidity sensor 80 and the temperature sensor 82, and the current light intensity is set as the optimum light intensity of the master LD array 18 for the slave n. Correspondingly, it is registered in the optimum light emission intensity table of the NVM memory 54.

  Next, the processing routine of the environment correction process shown in FIG. 8 will be described.

  In the environmental correction process, in step 400, sensor signals are taken from the humidity sensor 80 and the temperature sensor 82, and the current environmental temperature and environmental humidity are detected. In the next step 402, the environmental temperature and the environmental humidity registered with the set emission intensity are read from the optimum emission intensity table for the master LD array 18 for the slave n from the NVM memory 54, and the environment read in step 404 is read. Set the upper and lower limits for temperature and environmental humidity. The range from the upper limit value to the lower limit value is the allowable range of the environmental temperature and the environmental humidity at the set emission intensity.

  For example, as shown in Table 1 below, optical communication is possible with the set light emission intensity (light quantity level 3) until the third optimum light emission intensity detection process, that is, a light reception state notification is received from slave n. If the optical communication becomes impossible at the emission intensity set in the fourth detection process, the allowable temperature range is 20 ° C to 50 ° C and the allowable environmental humidity is based on the communication history up to the third time. The range is 40% to 70%. Since the current environmental temperature is 60 ° C. and the environmental humidity is 40%, the environmental temperature exceeds the allowable range. In this example, the light emission intensity can be changed at 10 light levels.

  In the next step 406, it is determined whether or not the environmental temperature or the environmental humidity exceeds each allowable range. When determination is denied, it transfers to step 418 and a flag is set. If the determination is affirmative, the flag is reset at step 408, and a drive signal for cooling or overheating each LD of the LD array 18 is output to the air cooling fan 84 or the heater 86 at step 410. As a result, when either the environmental temperature or the environmental humidity exceeds the upper limit value, the air cooling fan 84 is driven to cool each LD of the LD array 18, and either the environmental temperature or the environmental humidity reaches the lower limit value. When exceeding, the heater 86 is driven and each LD of the LD array 18 is heated.

  In the next step 412, it is determined whether or not a predetermined time has elapsed since the air cooling fan 84 or the heater 86 was driven. If the determination is negative, step 412 is repeated until the determination is positive. If the determination is affirmative, in the next step 414, ID is added to the intensity detection information, and emission intensity information indicating the emission intensity of each LD of the LD array 18 is added, and the set emission is set in step 416. Light emission intensity control information for causing each LD of the LD array 18 to emit light with an intensity is output to the LD driving unit 62 again.

  Then, the optical signal is transmitted again to the slave n with the same emission intensity. When the received light amount of each PD in the PD array 20 of the slave n matches the received light amount corresponding to the optimum state, in step 324 in FIG. 7, sensor signals are taken in from the humidity sensor 80 and the temperature sensor 82, and the current light emission intensity is slaved. The optimum emission intensity of the master LD array 18 for n is registered in the optimum emission intensity table of the NVM memory 54 in association with the current environment temperature, environment humidity, and ID of the slave n.

  For example, in the example shown in Table 1 above, as shown in Table 2 below, the air cooling fan 84 is driven and each LD of the LD array 18 is cooled, and the environmental temperature is set within the allowable range of 50 ° C. Optical communication is possible with the emitted light intensity (light level 3).

  As described above, by executing the environment correction processing, optical communication can be performed without increasing the set value of the light emission intensity even when the light emission intensity of each LD of the LD array 18 is reduced due to a change in environmental conditions. it can. In addition, the life of the master LD array 18 can be maximized, and the amount of heat generation can be suppressed to the minimum necessary.

  Next, with reference to FIG. 9, a processing routine of processing at the time of optical signal reception at each slave, which is performed according to the processing at the master described above, will be described.

  As described above, when the reception information from the master is input from the reception control unit 74 to the transmission control unit 52, the transmission control unit 52 executes the optical signal reception process. In this optical signal reception process, first, in step 500, the transmission destination ID included in the reception information is extracted, and it is determined whether or not the extracted transmission destination ID is the ID of the own device. It is determined whether the information is addressed to the device. If the determination is negative, the optical signal reception process is terminated without performing any process. Further, when the determination is affirmative (when the own apparatus is a slave n), the process proceeds to step 502, and the processes after step 502 are performed.

  If the received light amount of the optical signal in the slave n is within the allowable range of each PD of the PD array 20, the transmission control unit 52 executes the optical signal reception process and the determination in step 500 described above. Is affirmed and the routine proceeds to step 502, where it is determined whether or not the detection of the optimum light emission intensity for the own apparatus is being executed by the master by determining whether or not the received information is information for intensity detection. When determination is denied, it transfers to step 508, and it is determined whether reception information is information which notifies optimal light emission intensity. If this determination is also denied, the process proceeds to step 512, where the process corresponding to the content of the received information is executed, and the optical signal reception process is terminated.

  If the determination in step 502 is affirmed, the process proceeds to step 504, and the light reception state information indicating the light reception state of the optical signal by each PD of the PD array 20 based on the light reception amount information input from the signal processing unit 64. Is generated.

  As the light reception state information, for example, information indicating a deviation between a lower limit value of a light reception amount of each PD of the PD array 20 and an actual light reception amount of an optical signal by each PD of the PD array 20 can be applied. However, instead of this, information indicating the upper limit of the allowable range of the received light amount of each PD of the PD array 20 and the actual received light amount of the optical signal by each PD of the PD array 20 may be applied, Information representing the upper and lower limits of the allowable range of the received light amount of each PD of the PD array 20 and the actual received light amount of the optical signal by each PD of the PD array 20 may be applied.

  In step 506, the emission intensity information is extracted from the received information, and the extracted emission intensity information is added to the generated light reception state information, and the master ID is set as the transmission destination ID, and the ID of the own apparatus is set as the transmission source ID. After the addition, light emission intensity control information for causing each LD of the LD array 18 to emit light with a preset light emission intensity (the optimum light emission intensity detected last time may be applied instead) to the LD drive unit 62. In addition to outputting, the light reception state information to which the light emission intensity information is added is output to the LD driving unit 62 via the 8B / 10B encoder 56, the ECC generation unit 58, and the P / S conversion unit 60, and the processing at the time of receiving the optical signal is finished. .

  Thereby, each LD of the LD array 18 of the slave n is turned on / off according to the reception state information so that the light emission intensity at the time of lighting (light emission) matches the set light emission intensity. The optical signal modulated in accordance with the state information is emitted from the LD array 18 of the slave n and transmitted to one of the second optical fibers 36, 38, 40, the optical sheet bus 42B, the first optical fiber 28, and then the master signal. Light is received by the PD array 20.

  After the determination in step 500 is affirmed, the determination in step 502 is denied, the determination in step 508 is affirmed, and the process proceeds to step 510. The optimum light emission intensity of the master LD array 18 for the slave n notified from the master is determined. It is stored in the NVM memory 54 of the slave n. Thus, the NVM memory 54 of each slave corresponds to the second storage means according to the present invention.

  When the optimum emission intensity detection process at the master is completed, the master transmission control unit 52 detects the optimum emission intensity of each LD of the LD array 18 of each slave when transmitting information to the master to each slave. Predetermined information for instructing the execution of the processing is sequentially transmitted by optical communication. Thereby, in the slave (referred to as “slave n” for convenience) instructed to execute the process of detecting the optimum emission intensity by receiving the predetermined information, the optimum emission intensity detection process is executed by the transmission control unit 52. The

  The optimum light emission intensity detection process executed by the slave is a process corresponding to the setting means according to the present invention, and the transmission control unit 52 of the slave optical communication control unit 22 executes the optimum light emission intensity detection process. It functions as setting means according to the present invention.

(Optimal emission intensity detection process executed by the slave)
Next, with reference to FIG. 10, the processing routine of the optimum light emission intensity detection process in the slave will be described.

  First, in step 600, the NVM memory 54 is referenced to determine whether or not the optimum emission intensity of the slave n LD array 18 is registered in the optimum emission intensity table of the NVM memory 54. If the determination is negative, the process proceeds to step 602 and an initial setting process is performed. If the determination is affirmed in step 600, the process proceeds to step 604 and a normal setting process is performed. As a result, the optimum emission intensity of the slave LD array 18 is detected, and the detected optimum emission intensity is registered in the optimum emission intensity table of the NVM memory 54 and notified to the master.

  In the initial setting process of the master, a predetermined value is set as an initial value and a change range of the light emission intensity of each LD of the LD array 18 for detecting the optimum light emission intensity of the master LD array 18 with respect to the slave n in Step 200. In the initial setting process of the slave, first, the optimum light emission intensity notified from the master and stored in the NVM memory 54 (the optimum light emission intensity of the master LD array 18 for the slave n) is read, and the optimum light emission intensity detected this time is the NVM memory 54. Based on the read optimum light intensity on the assumption that the value is the same or approximate to the optimum light intensity read from (the optimum light intensity of the master LD array 18 for the slave n detected and notified by the master) The initial value and change range of the light emission intensity of each LD of the LD array 18 of the slave n are set. Thereby, the time required for the optimum light emission intensity detection process can be shortened.

  The initial setting process of the slave is the same processing routine as the initial setting process of the master shown in FIG. The slave normal setting process is the same processing routine as the slave normal setting process shown in FIG.

  Next, with reference to FIG. 11, the processing routine of the optical signal reception process at the master, which is performed according to the above-described processing at each slave, will be described.

  As described above, the reception information from each slave is input from the reception control unit 74 to the transmission control unit 52, whereby the transmission control unit 52 executes an optical signal reception process. In this optical signal reception process, first, in step 700, the transmission destination ID included in the reception information is extracted, and it is determined whether or not the extracted transmission destination ID is the ID of the own device. It is determined whether the information is addressed to the device. If the determination is negative, the optical signal reception process is terminated without performing any process.

  If the determination is affirmative, the routine proceeds to step 702, and the processing after step 702 is performed. In the configuration of the present embodiment, all the information transmitted by each slave is information addressed to the master, and the determination in step 700 is not denied, so step 700 may be omitted.

  When the received light amount of the optical signal in the master is within the allowable range of each PD of the PD array 20, the transmission control unit 52 of the master executes the optical signal reception process and the determination in step 700 is performed. If the result is affirmative and the process proceeds to step 702, it is determined whether or not the detection of the optimum light emission intensity for the own apparatus is being executed by the slave n by determining whether or not the received information is information for intensity detection. When determination is denied, it transfers to step 710, the process according to the content of reception information is performed, and the process at the time of optical signal reception is complete | finished.

  If the determination in step 702 is affirmed, the process proceeds to step 704, and the light reception state information indicating the light reception state of the optical signal by each PD of the PD array 20 based on the light reception amount information input from the signal processing unit 64. Is generated.

  In step 706, the emission intensity information is extracted from the received information. In step 708, the extracted emission intensity information is added to the generated light reception state information, and the ID of slave n is set as the transmission destination ID. After each ID of the device (master) is added, the emission intensity control information for causing each LD of the LD array 18 to emit light with the optimum emission intensity for the slave n previously detected and registered in the optimum emission intensity table is LD. Output to the drive unit 62.

  In addition, the light reception state information (transmission information) to which the light emission intensity information is added is output to the LD driving unit 62 via the 8B / 10B encoder 56, the ECC generation unit 58, and the P / S conversion unit 60, and processing at the time of receiving the optical signal is performed. finish. Thereby, the light reception state information to which the slave n and master ID and light emission intensity information are added is transmitted from the master to the slave n by optical communication.

  As described above, in the present embodiment, when the detection of the optimum light emission intensity for the optical communication partner is completed in the master and each slave, normal optical communication is performed. When transmitting information to the slave, the master transmission control unit 52 reads out the optimum light emission intensity registered in the optimum light emission intensity table of the NVM memory 54 in association with the ID of the information transmission target slave, and reads the optimum light emission thus read out. Light emission intensity control information for causing each LD of the LD array 18 to emit light with an intensity is output to the LD driving unit 62.

  This process corresponds to the first control means according to the present invention, and by executing this process, the master transmission control unit 52 functions as the first control means according to the present invention. Thereby, when transmitting information from the master to an arbitrary slave, the light emission intensity of each LD of the LD array 18 of the master is controlled so that the received light amount of the optical signal in the slave of the information transmission destination becomes an optimum state.

  When an arbitrary slave (slave n) transmits information to the master, the transmission control unit 52 of the slave n uses the optimum emission intensity stored in the NVM memory 54 (the optimum emission intensity of the LD 18 of the slave n with respect to the master). , And outputs light intensity control information for causing each LD of the LD array 18 to emit light with the read optimum light intensity.

  As a result, even when information is transmitted from any slave n to the master, the light emission intensity of each LD of the LD array 18 of the slave n is controlled so that the received light amount of the optical signal at the master is in an optimum state. This processing corresponds to the second control means according to the present invention, and by executing this processing, the slave transmission control unit 52 functions as the second control means according to the present invention. As a result, when transmitting information from an arbitrary slave to the master, the light emission intensity of each LD of the slave LD array 18 is controlled so that the received light amount of the optical signal at the information transmission destination master is in an optimum state.

  Thus, in the present embodiment, the optimum light emission intensity of the master LD array 18 for each slave is detected by the master, and when the master transmits information to any slave, the light emission intensity of each LD of the LD array 18 Since control is performed so that the optimal emission intensity corresponding to the slave of the information transmission destination is obtained, information can be reliably transmitted to each slave by optical communication, and the emission intensity of the LD array 18 is optimal for each slave. Therefore, it is possible to prevent the life of the LD array 18 from being adversely affected by the light emitted from the master LD array 18 with a light emission intensity higher than necessary or prevent the LD array 18 from generating heat more than necessary.

  In particular, in the present embodiment, when the optimum light emission intensity is detected by the master and each slave, an “environment correction process” for correcting the current environmental condition to an environmental condition capable of emitting light is executed. Even when the light emission intensity of each LD of the LD array 18 decreases, optical communication can be performed without increasing the set value of the optimum light emission intensity. Further, since the set value of the optimum light emission intensity is not increased, the life of the LD array 18 can be extended to the maximum, and the amount of heat generated by the LD array 18 can be suppressed to the minimum necessary.

[Environmental adaptation processing]
In the above embodiment, an example has been described in which the “environment correction process” is performed to correct the current environmental condition to the environmental condition capable of emitting light when the light receiving state is not notified from the communication partner in the normal setting process. Instead of performing the “environment correction process”, an “environment adaptation process” for setting the light emission intensity that can be emitted under the current environmental conditions can be performed.

  Next, a processing routine for environment adaptation processing will be described with reference to FIG.

  In the environmental adaptation processing, sensor signals are taken from the humidity sensor 80 and the temperature sensor 82 in step 800, and the current environmental temperature T and environmental humidity W are detected as the current environmental conditions. In the next step 802, the light emission intensity registered at the current environmental temperature and environmental humidity for the master LD array 18 for the slave n is retrieved from the NVM memory 54 from the optimum light emission intensity table. In step 804, on the assumption that the optimum emission intensity detected this time is the same or approximate to the searched emission intensity, the initial value of the emission intensity of each LD of the LD array 18 based on the searched emission intensity, and Set the change range.

  In the next step 806, ID is added to the intensity detection information, and emission intensity information indicating the emission intensity of each LD of the LD array 18 is added. In step 808, each LD of the LD array 18 is set with the set emission intensity. The light emission intensity control information for causing the light to be emitted is output to the LD driving unit 62 again.

  As described above, by executing the environment adaptation processing, even when the light emission intensity of each LD of the LD array 18 is reduced due to the change in the environmental condition, the optimum light emission intensity corresponding to the environmental condition can be obtained by searching the communication history. The optical communication can be performed with the set optimum light emission intensity.

It is a block diagram which shows schematic structure of the optical communication system which concerns on this Embodiment. It is a perspective view which shows the external appearance of an optical sheet bus | bath. It is a perspective view which shows the waveguide member embed | buried under the base member of the optical sheet bus | bath. It is a block diagram which shows schematic structure of an optical communication control part. It is a flowchart which shows the process routine of the optimal light emission intensity detection process performed with a master. It is a flowchart which shows the processing routine of an initialization process. It is a flowchart which shows the process routine of a normal setting process. It is a flowchart which shows the process routine of an environmental correction process. It is a flowchart which shows the process routine of the process at the time of the optical signal reception performed by a master. It is a flowchart which shows the process routine of the optimal light emission intensity detection process performed with a slave. It is a flowchart which shows the process routine of the process at the time of the optical signal reception performed with a slave. It is a flowchart which shows the process routine of an environment adaptation process.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Electronic device 12 Electronic circuit 14 Optical communication system 16 Optical communication I / F part 18 LD array 20 PD array 22 Optical communication control part 26 Optical fiber 28 Optical fiber 30 Optical fiber 32 Optical fiber 34 Optical fiber 36 Optical fiber 38 Optical fiber 40 Optical fiber 42 Optical sheet bus 52 Transmission control unit 54 NVM memory 80 Humidity sensor 82 Temperature sensor 84 Air cooling fan 86 Heater

Claims (4)

Optical communication that includes a light-emitting element that transmits optical signals and a light-receiving element that receives optical signals, is connected to multiple devices via a distributed optical signal transmitter, and can transmit and receive optical signals to and from multiple devices A device,
A light emitting element driving unit that drives the light emitting element based on light emission intensity control information;
A reception information acquisition unit that acquires reception information including a reception state of a device that communicates from an optical signal received by the light receiving element;
Measuring means for measuring the environmental temperature and the environmental humidity where the light emitting element is placed;
A correction unit that drives at least one of a heating unit and a cooling unit that adjust the environmental temperature and the environmental humidity, and corrects at least one of the environmental temperature and the environmental humidity where the light emitting element is placed;
For each of a plurality of connected devices, a setting value of the light emission intensity of the light emitting element, an environmental temperature and an environmental humidity measured by the measuring means when light is emitted with the setting value of the light emission intensity, and a setting of the light emission intensity Light emission including optimum light emission intensity information for causing the light emitting element to emit light at an optimum light emission intensity by associating the reception information acquired by the reception information acquisition unit when emitting light with a value or the presence or absence of acquisition of the reception information. Storage means stored as intensity control information;
Based on the light emission intensity control information, the light emitting element driving unit drives the light emitting element to transmit an optical signal for intensity detection including optimum light emission intensity information for each of the plurality of devices.
When the reception information cannot be acquired by the reception information acquisition unit,
When at least one of the environmental temperature and the environmental humidity exceeds an upper limit value, the cooling unit is driven to cool the light emitting element, and when at least one of the environmental temperature and the environmental humidity falls below a lower limit value, the heating unit is driven. Then , after correcting at least one of environmental temperature and environmental humidity by the correction means so that the light emitting element is heated , the light signal for intensity detection is transmitted again based on the light emission intensity control information , or the measurement is performed. The setting value of the emission intensity is changed according to the environmental temperature and the environmental humidity measured by the means, and the intensity detection optical signal including the optimal emission intensity information after the change is transmitted again,
If the reception information can be acquired by the reception information acquisition unit, a control means for controlling to detect new emission intensity control information based on the acquired reception information and store it in the storage means;
An optical communication device comprising:   The optical communication device according to claim 1, wherein the distribution type optical signal transmission body is connected to the distribution optical signal transmission body by an optical fiber, and the distribution type optical signal transmission body and each of the plurality of devices are connected to each other by an optical fiber. When transmitting an optical signal to an additional device in which the light emission intensity control information is not stored in the storage unit, the control unit is controlled by the light emitting element driving unit based on the light emission intensity control information set in advance. When the light emitting element is driven to transmit an optical signal for intensity detection to the additional device and the reception information cannot be acquired by the reception information acquisition unit, a setting value of the light emission intensity is set until the reception information can be acquired. If the received information acquisition unit can acquire the received information again while increasing the intensity in steps, the new emission intensity control information is detected based on the acquired received information. The optical communication device according to claim 1, wherein the optical communication device is controlled so as to be stored in the storage unit. Each of the plurality of devices receives reception information including reception status when receiving an optical signal for intensity detection, and storage means for storing optimum emission intensity information included in the optical signal for intensity detection Including,
The reception information acquisition unit receives the reception information generated by the reception information generation unit of the device that has transmitted the optical signal for detecting the intensity together with the optimum emission intensity information. The optical communication device according to Item.

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