JP2006180241A - Optical communication apparatus and optical communication ion method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical communication apparatus having a plurality of channels which can efficiently suppress power consumption by setting optimum light intensity with a simple configuration, and an optical communication method. <P>SOLUTION: An optical communication control unit 22 of a master transmits predetermined pattern signals to each slave at a plurality of kinds of light intensity. An optical communication control unit 22 of each slave determines whether or not a predetermined pattern signal transmitted from the master is normally recognized, and notifies the master of light intensity commonly receivable between respective PDs of the slave. The master sets the light intensity of the LD at the minimum light intensity among the light intensities commonly receivable by respective slaves. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an optical communication device and an optical communication method, and more specifically, an optical communication connected to another optical communication device via an optical fiber and a distributed optical signal transmitter, and having a plurality of light emitting elements and light receiving elements. The present invention relates to an apparatus and an optical communication method.

  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 referred to as optical sheet buses) and optical transmission systems including the distribution type optical signal transmission bodies have been proposed.

  As an optical transmission system using such an optical sheet bus, for example, one device (hereinafter referred to as a master) and one or more identical devices (hereinafter referred to as slaves) are connected using an optical sheet bus. is there.

  In this case, since the optical sheet bus has a function of distributing signals, when the transmission path of the same component (material) is used, the amount of light lost in the transmission path can be measured by any slave. It will be almost the same. For this reason, the master optical transmitter usually adjusts the light intensity to ensure that all slave receivers have a light intensity greater than the minimum received light amount, or the DC balance (hereinafter referred to as DC balance) such as the light intensity of the signal and the on / off balance. The signal can be transmitted by improving the responsiveness of the photodiode of the receiver.

  However, when considering the transmission path from the optical sheet bus to the slave, there is a loss when the transmission distance is not the same, a loss of the coupling part and a loss due to differences in parts (materials), etc. There may be a difference in quantity. For example, when POF (Plastic Optical Fiber) is used as an optical fiber, there is a high possibility that a difference occurs in the amount of received light that can be received for each slave depending on the length of the transmission path.

  Also, it may be possible to use the system as a system in which the transmission distance from the optical sheet bus to the slave is intentionally changed. In this case, as a master, there is a method to increase the light intensity of the light emitting element of the optical transmitter in accordance with the slave with the least amount of received light (slave slave), but the life of the light emitting element depends on the light intensity. It becomes shorter in inverse proportion and is not necessarily preferable. In addition, increasing the light intensity may cause an increase in power consumption and heating problems.

As a technique for suppressing such wasteful power consumption, a technique described in Patent Document 1 has been proposed. In the technique described in Patent Document 1, a receiver capable of detecting a reception level is provided in a child node in mutual communication between the parent node and a plurality of child nodes, and the reception level of the parent node is actually received as a fixed level. There has been proposed a technique for determining the transmission level of the child node by comparing the attenuated level and estimating the distance to the parent node. In the technique described in Patent Document 7, the transmission level of the parent node is fixed and the child level is fixed. Since the transmission level of the node is adjusted, wasteful power consumption of a child node close to the parent node can be suppressed.
Japanese Patent Laid-Open No. 11-163797

  However, although the technology described in Patent Document 1 can suppress the wasteful power consumption of the child node, the transmission level of the parent node, which generally tends to increase the power consumption, is fixed. There is a problem that power consumption cannot be suppressed.

  Further, the technique described in Patent Document 1 is a technique when there are one light emitting element and one light receiving element, that is, one channel, and cannot be applied when there are a plurality of light emitting elements and light receiving elements, that is, a plurality of channels.

  The present invention has been made to solve the above problems, and in an optical communication apparatus having a plurality of channels, an optical communication capable of setting an optimum light intensity with a simple configuration and effectively suppressing power consumption. An object is to provide an apparatus and an optical communication method.

  In order to achieve the above object, the invention described in claim 1 comprises a plurality of first light emitting elements and a plurality of first light receiving elements, a first optical fiber for transmission, an optical sheet bus for transmission, and a plurality of elements for transmission. A plurality of other optical communication devices are connected to each other via the second optical fiber, and the plurality of other optical communication devices are connected via the first optical fiber for reception, the optical sheet bus for reception, and the plurality of second optical fibers for reception. In the optical communication devices respectively connected to the optical communication devices, a plurality of the other optical communication devices receive a predetermined pattern signal from the first light emitting elements of the plurality of first light emitting elements at a plurality of different light intensities. Each of the plurality of optical communication devices receives the reception result information when the predetermined pattern signal is received by each of the plurality of second light receiving elements included in the other optical communication devices. Receiving means for Based on the reception result information transmitted from another optical communication apparatus having, characterized by comprising a setting means for setting the light intensity of the plurality of first light-emitting element.

  According to this invention, the optical communication device includes a plurality of first light emitting elements and a plurality of first light receiving elements. The optical communication device is connected to a plurality of other optical communication devices via the first transmission optical fiber, the transmission optical sheet bus, and the plurality of second transmission optical fibers. Thereby, the optical signal emitted from the first light emitting element is transmitted to the other optical communication device by propagating through the first optical fiber for transmission, the optical sheet bus for transmission, and the second optical fiber for transmission. Light is received by the second light receiving element of the optical communication device.

  The optical communication device is connected to each of a plurality of other optical communication devices via a first receiving optical fiber, a receiving optical sheet bus, and a plurality of second receiving optical fibers. As a result, the optical signal emitted from the second light emitting element of the other optical communication device propagates through the second optical fiber for reception, the optical sheet bus for reception, and the first optical fiber for reception. Received light.

  In such an optical communication apparatus, the transmission means transmits a predetermined pattern signal from each of the first light emitting elements to the other optical communication apparatuses at a plurality of different light intensities. Let

  The receiving unit receives, from each of the plurality of other optical communication devices, reception result information when the predetermined pattern signal is received by each of the plurality of second light receiving elements included in each of the other optical communication devices.

  The setting means sets the light intensity of the plurality of first light emitting elements based on the reception result information transmitted from the plurality of other optical communication devices.

  Thus, in order to set the light intensity of the first light emitting element based on the reception result when the predetermined pattern signal is transmitted from one of the first light emitting elements to another optical communication device instead of every first light emitting element. The apparatus can be simplified, and the light intensity is set based on the reception result when the predetermined pattern signal is transmitted to another optical communication apparatus with a plurality of different light intensities, so that the optimum light intensity is set. It becomes possible.

  In addition, as described in claim 2, the setting unit is configured to receive light that can be normally received by all of the plurality of second light receiving elements respectively provided in the plurality of other optical communication devices based on the reception result information. It is preferable that the intensity is extracted, and a predetermined light intensity among the extracted light intensity is uniformly set as the light intensity of the plurality of first light emitting elements. Thereby, the light intensity can be appropriately set regardless of variations in sensitivity of the second light receiving elements of other optical communication devices.

  According to a third aspect of the present invention, the predetermined light intensity is preferably the lowest light intensity among the extracted light intensities. Thereby, useless power consumption can be suppressed and the lifetime of the first light emitting element can be extended.

  According to a fourth aspect of the present invention, the setting unit may notify the host device when the light intensity that can be normally received cannot be extracted.

  In addition, as described in claim 5, the second light receiving element having the highest minimum light intensity that can be normally received is inspected among the plurality of second light receiving elements provided in each of the plurality of other optical communication devices. It is good also as a structure further provided with the confirmation means which is set as a light receiving element for confirmation, and confirms the reception condition of the set light receiving element for an inspection. As a result, it is possible to reset the light intensity to an optimum level according to the confirmed reception status, and it is possible to always perform good optical communication.

  According to a sixth aspect of the present invention, a plurality of first light emitting elements and a plurality of first light receiving elements are provided, and a plurality of the first light emitting elements are transmitted via the first transmitting optical fiber, the transmitting optical sheet bus, and the plurality of transmitting second optical fibers. Connected to each of the other optical communication devices, and connected to the other optical communication devices via the first optical fiber for reception, the optical sheet bus for reception, and the plurality of second optical fibers for reception. In the optical communication device, a predetermined pattern signal transmitted at a plurality of different light intensities from any one of the plurality of second light emitting elements included in the other optical communication device is transmitted to the other optical communication device. Receiving means for receiving each of the optical communication devices, setting means for setting the light intensity of the plurality of second light emitting elements based on the reception result of the predetermined pattern signal, and the set light intensity for the other light Notification to notify each communication device Characterized by comprising a stage, a.

  According to this invention, the receiving means receives a plurality of predetermined pattern signals transmitted at a plurality of different light intensities from any one of the plurality of second light emitting elements included in another optical communication device. Each of the other optical communication devices receives the information.

  The setting means sets the light intensity of the plurality of second light emitting elements based on the reception result of the predetermined pattern signal.

The notifying means notifies the set light intensity to each of a plurality of other optical communication devices, and
Thus, in order to set the light intensity of the second light emitting element based on the reception result when the predetermined pattern signal transmitted from any of the second light emitting elements is received instead of every second light emitting element, the apparatus is In addition to being able to simplify, since the light intensity is set based on the reception result when the predetermined pattern signal transmitted at a plurality of different light intensities is received, it is possible to set the optimum light intensity.

  According to the seventh aspect of the present invention, the setting means sets the light intensity that can be normally received by all of the plurality of first light receiving elements for each of the plurality of other optical communication devices based on the reception result. It is preferable that the extracted light intensity is uniformly set as the light intensity of the plurality of second light emitting elements. Thereby, it is possible to appropriately set the light intensity regardless of variations in sensitivity of the first light receiving element.

  In addition, as described in claim 8, the predetermined light intensity is preferably the lowest light intensity among the extracted light intensities. Thereby, useless power consumption can be suppressed and the lifetime of the second light emitting element can be extended.

  According to a ninth aspect of the present invention, the setting unit may notify the host device when the light intensity that can be normally received cannot be extracted.

  In addition, as described in claim 10, for each of the plurality of other optical communication devices, the first light receiving element having the highest minimum light intensity that can be normally received among the plurality of first light receiving elements is inspected. It may be configured to further include a confirmation unit that is set as each light receiving element and confirms the reception status of the set inspection light receiving element. As a result, it is possible to reset the light intensity to an optimum level according to the confirmed reception status, and it is possible to always perform good optical communication.

  The invention according to claim 11 includes a plurality of first light emitting elements and a plurality of first light receiving elements, and a plurality of the plurality of first light emitting elements via the first optical fiber for transmission, the optical sheet bus for transmission, and the second optical fibers for transmission. Connected to each of the other optical communication devices, and connected to the other optical communication devices via the first optical fiber for reception, the optical sheet bus for reception, and the plurality of second optical fibers for reception. In the optical communication method executed by the optical communication device, the plurality of other optical communication devices receive a predetermined pattern signal from the first light emitting element of the plurality of first light emitting elements at a plurality of different light intensities. Each of the plurality of optical communication devices, and receiving each of the predetermined pattern signals by the plurality of second light receiving elements included in each of the other optical communication devices, respectively. From multiple other optical communication devices Based on the signal reception result information, to set the light intensity of the plurality of first light-emitting element, characterized in that.

  According to the present invention, the light intensity of the first light emitting element is set based on the reception result when the predetermined pattern signal is transmitted from one of the first light emitting elements to another optical communication device instead of every first light emitting element. Therefore, the apparatus can be simplified, and the light intensity is set based on the reception result when the predetermined pattern signal is transmitted to another optical communication apparatus with a plurality of different light intensities. It becomes possible to set.

  According to a twelfth aspect of the present invention, a plurality of first light emitting elements and a plurality of first light receiving elements are provided. Connected to each of the other optical communication devices, and connected to the other optical communication devices via the first optical fiber for reception, the optical sheet bus for reception, and the plurality of second optical fibers for reception. In the optical communication method executed by the optical communication device, the predetermined pattern signal transmitted at a plurality of different light intensities from any one of the plurality of second light emitting devices included in the other optical communication device. For each of the plurality of other optical communication devices, and based on the reception result of the predetermined pattern signal, sets the light intensity of the plurality of second light emitting elements, and sets the set light intensity to the plurality of other optical communication devices. Notify each optical communication device It is characterized in.

  According to this invention, in order to set the light intensity of the second light emitting element based on the reception result when receiving the predetermined pattern signal transmitted from any of the second light emitting elements instead of every second light emitting element. It is possible to simplify the device and set the light intensity based on the reception result when receiving a predetermined pattern signal transmitted with a plurality of different light intensities, so that the optimum light intensity can be set. Become.

  As described above, according to the present invention, in an optical communication apparatus having a plurality of channels, there is an effect that an optimum light intensity can be set with a simple configuration and power consumption can be effectively suppressed.

  Hereinafter, embodiments of the present invention will be described.

  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 realized between the electronic circuit 12A and the electronic circuits 12B to 12D. An optical communication system 14 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) LDs (laser diodes: light emitting elements) are arranged in a line, and a plurality of LD arrays 18 are arranged. A PD array 20 in which (for example, five) PDs (photodiodes: light receiving elements) are arranged in a row, an optical communication control unit 22 connected to the electronic circuit 12, the LD array 18 and the PD array 20, respectively, and a memory 23 is provided.

  In the present embodiment, a case where the LD array 18 includes five LDs and the PD array 20 includes five PDs, that is, a case where a five-channel LD array 18 and a PD array 20 are provided will be described.

  Each of the LD array 18 and the PD array 20 of the optical communication I / F unit 16 is configured so that the optical connector 24 is detachable, and the LD array 18 (a plurality of first light emitting elements) of the optical communication I / F unit 16A. ) Connected to the optical connector 24, one end of the first optical fiber 26 (first optical fiber for transmission) is connected to the optical connector 24 attached to the PD array 20 (a plurality of first light receiving elements). One end of a fiber 28 (first optical fiber for reception) is attached, and the second optical fiber 36 (second optical fiber for reception) is connected to the optical connector 24 connected to the LD array 18 of the optical communication I / F unit 16B. One end of the second optical fiber 30 (second optical fiber for transmission) is attached to the optical connector 24 attached to the PD array 20. Similarly, one end of the second optical fiber 38 (second optical fiber for reception) is connected to the optical connector 24 connected to the PD array 20 in the optical connector 24 connected to the LD array 18 of the optical communication I / F unit 16C. One end of the second optical fiber 32 (second optical fiber for transmission) is attached to the optical connector 24 connected to the LD array 18 of the optical communication I / F unit 16D. One end of the second optical fiber (for transmission) is attached to the optical connector 24 connected to the PD array 20.

  The first optical fibers 26, 28 and the second optical fibers 30, 32, 34, 36, 38, 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 also in FIG. 2, optical connectors 24 are attached to the other ends of the first optical fiber 26 and the second optical fibers 30, 32, 34, respectively, and these optical connectors 24 are connected to the optical sheet bus 42A (transmission light). To the seat bus). Although not shown in detail, the optical connectors 24 are attached to the other ends of the first optical fiber 28 and the second optical fibers 36, 38, 40, respectively, and these optical connectors 24 are connected to the optical sheet bus 42B (receiver). Optical sheet bus).

  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.

  Next, the operation of the optical communication control unit 22 provided in each of the optical communication I / F units 16A to 16D will be described.

  Hereinafter, the optical communication I / F unit 16A is simply referred to as “master”, and the optical communication units I / F units 16B to 16D are simply referred to as “slave 1”, “slave 2”, and “slave 3”.

  First, the operations of the master and slaves 1 to 3 when setting the light intensity of the master LD will be described with reference to the flowcharts shown in FIGS. This process is executed by each device at predetermined time intervals, for example.

  In step 100 shown in FIG. 4, the master optical communication control unit 22 determines whether or not a master strength adjustment start command transmitted from the electronic circuit 12A as the host device is received. If YES in step 102, the flow shifts to step 102.

  In step 102, a NotReady signal indicating that preparation is in progress is sent to the electronic circuit 12A to notify that normal data transmission is not possible.

  In step 104, the number of nodes S representing the number of slaves connected to the master is set (here, “3” is set), and a variable n representing the number of the slave is initialized (here, “1” is set). To do.

  In step 106, a variable m representing the light intensity is initialized (here, “1” is set), and in step 108, a master intensity adjustment start command is transmitted to slave n. This command is first transmitted at the maximum light intensity that can be emitted by the master LD. In the present embodiment, a case will be described in which each of the master and slave LDs can emit light with a light intensity of ‘1’ to ‘7’. That is, in this case, the intensity adjustment start command is transmitted with the light intensity “7”.

  Since the slave n transmits a response signal indicating whether or not the master strength adjustment start command has been normally received to the master, the master receives the response signal and performs corresponding processing. Specifically, if the response signal is a signal indicating that the slave n has successfully received the master strength adjustment start command, the process directly proceeds to step 110 to indicate that the slave n has not been received normally. If it is a signal, the master intensity adjustment start command is transmitted with the light intensity level lowered by one, and the same processing as described above is performed. As described above, slave n may not be able to receive even if the master intensity adjustment start command is transmitted at the maximum light intensity. The main reason is that the transmission distance between the master and the slave is extremely short and the sensitivity of the light receiving element. This is because the light receiving element is saturated and cannot be received.

  Such processing is repeated until the master n adjustment start command can be normally received on the slave n side. If the slave n cannot normally receive the master intensity adjustment start command with all the light intensities, an error may be notified to the electronic circuit 12A, and this routine may be terminated.

  For each command to be described later, a master intensity adjustment start command is transmitted at a light intensity that can be normally received by the slave n.

  In step 110, a predetermined pattern signal corresponding to the light intensity m is transmitted at a light intensity m from any LD in the LD array 18. This pattern signal may be a fixed pattern signal with DC balance. However, in order to approximate the actual transmission state, it is preferable to sequentially switch and transmit a plurality of pattern signals so as to form an eye pattern.

  In step 112, m is incremented, and in step 114, it is determined whether m is larger than the maximum light intensity (here, “7”). If m is less than the maximum light intensity, the process returns to step 110 and returns to the above. The same process is repeated, and if m is larger than the maximum light intensity, that is, if the processes of steps 110 and 112 are performed for all the light intensities, the process proceeds to step 116.

  In step 116, an intensity adjustment end command is transmitted to slave n. In step 118, n is incremented.

  In step 120, it is determined whether or not n is greater than the number of slaves S. If n is less than or equal to the number of slaves S, the process returns to step 106 and the same processing is repeated, and n is greater than the number of slaves S. That is, if the processing of steps 106 to 120 is performed for all the slaves, the process proceeds to step 122.

  In step 122, n is initialized again (here, set to "1"). In step 124, a notification start command for requesting the slave n to start notification of the reception result at each light intensity is transmitted.

  In step 126, light intensity information, which is information indicating the light intensity receivable by slave n and transmitted from slave n, is received. The light intensity information is information indicating the light intensity that can be normally received in common by each PD when it is determined whether or not the predetermined pattern signal transmitted from the master at each light intensity can be normally recognized by each PD of the slave. That is, it includes at least the maximum light intensity and the minimum light intensity values among the light intensities that can be commonly received by each PD of the slave. This light intensity information is stored in the memory 23 of the master.

  Here, FIG. 6 shows an example of a correspondence relationship 50 between the light intensity of the LD of the master and the reception result of each PD of each slave when a predetermined pattern signal is transmitted to the slave at each light intensity. Note that “◯” in the correspondence relationship 50 indicates that the predetermined pattern of the light intensity was normally recognized by the slave, and “×” indicates that it was not normally recognized.

  In this case, since the light intensity that can be received in common by each PD of the slave 1 is “3” to “6”, “3” to “6” are set in the light intensity information transmitted from the slave 1. Is done.

  In step 128, n is incremented. In step 130, it is determined whether or not n is greater than the number of slaves S. If n is less than or equal to the number of slaves S, the process returns to step 124 and the same processing is repeated, and if n is greater than the number of slaves S. That is, if the processing of steps 124 to 128 is performed for all slaves, the process proceeds to step 132.

  In step 132, based on the received light intensity information, the light intensity that can be received in common by each PD of each slave is extracted. For example, in the example of FIG. 6, the light intensity that can be commonly received by each PD of the slave 1 is “3” to “6”, and the light intensity that can be commonly received by each PD of the slave 2 is “4”. Since the light intensity that can be received in common by each PD of the slave 3 is “2” to “5”, the light intensity that can be received in common in all the PDs of the slaves 1 to 3 is “7”. 4 'and' 5 '.

  In step 134, it is determined whether or not there is a light intensity that can be received in common by all PDs. If it exists, the process proceeds to step 136, and if it does not exist, the process proceeds to step 138.

  In step 136, the light intensity of each master LD is set. Specifically, for example, the light intensity that can be received by all the PDs of each slave is set to the lowest intensity. In the example of FIG. 6, the light intensity that can be commonly received by all the PDs of the slaves 1 to 3 is either “4” or “5”. The light intensity of each LD of the master is uniformly set to “4”.

  As described above, the light intensity of the LD of the master is preferably set uniformly for all the slaves in consideration of the case where the master has no time for switching the slave that is the transmission destination. If there is enough time, it may be set for each slave. In this case, for example, in the example of FIG. 6, the light intensity is set to “3” for the slave 1, the light intensity is set to “4” for the slave 2, and the light intensity is set to “2” for the slave 3. Thereby, it becomes possible to suppress power consumption more effectively.

  In the next step 140, a Ready signal indicating that preparation for data communication is completed is transmitted to the electronic circuit 12A.

  On the other hand, in step 138, since there is no light intensity that can be received in common in all the PDs of the slaves 1 to 3, an error is notified to the electronic circuit 12A.

  As described above, in this embodiment, the light intensity that can be received in common in all the PDs of the slaves 1 to 3 is extracted, and the light intensity is selected and set from the light intensity. For this reason, the optimum light intensity can be set regardless of variations in the light amount of the LD, the sensitivity of the PD, the loss of the transmission path, and the like, and good optical communication can be performed.

  In this embodiment, the intensity of the LD of the master is not adjusted for each channel, but the light intensity of each channel is uniformly set, and the light intensity of the master can be received in common by each PD of the slave. The minimum light intensity is set. For this reason, the apparatus can have a simple configuration, and the life of the apparatus can be extended while suppressing power consumption.

  Next, processing executed in each slave will be described with reference to a flowchart shown in FIG. This process is executed every predetermined time.

  In step 200, it is determined whether or not the master strength adjustment start command has been normally received from the master. If the master strength adjustment start command has been normally received, the process proceeds to step 201, where a response signal indicating normal reception is transmitted to the master and received normally. If not, the process proceeds to step 224, and after transmitting a response signal indicating abnormal reception to the master, this routine is terminated.

  In step 202, a variable m indicating the light intensity is initialized (here, “1” is set), and in step 204, a predetermined pattern signal corresponding to the light intensity m transmitted from the master is received by each PD.

  In step 206, it is determined whether or not the predetermined pattern signal received by each PD can be recognized normally. Here, each slave stores a pattern of a predetermined pattern signal corresponding to the light intensity in each memory 23. Accordingly, whether or not the received predetermined pattern signal can be normally recognized is determined based on the pattern of the predetermined pattern signal corresponding to the received light intensity m and the pattern of the predetermined pattern signal corresponding to the light intensity m stored in the memory 23. What is necessary is just to judge whether or not.

  If the received predetermined pattern signal can be recognized normally, the process proceeds to step 208, and '1' is substituted for the variable Hx for substituting the reception result. The process proceeds to step 210, and “0” is substituted for the variable Hx. 'X' indicates a channel number, that is, a PD number. Further, “1” corresponds to “◯” in the correspondence relationship 50 in FIG. 6, and “0” corresponds to “×”.

  In step 212, the light intensity m, the channel number x, and the variable Hx that is the reception result are stored in the memory 23 as reception result information.

  In step 214, the light intensity m is incremented, and in step 216, it is determined whether m is larger than the maximum light intensity (here, “7”). If m is less than or equal to the maximum light intensity, the process returns to step 204 and the same processing is repeated. If m is greater than the maximum light intensity, that is, steps 204 to 214 are performed for predetermined pattern signals of all light intensities. If the above process is performed, the process proceeds to step 218.

  In step 218, it is determined whether or not an intensity adjustment end command transmitted from the master is received. If not received, the process waits until it is received. If received, the process proceeds to step 218.

  In step 220, it is determined whether or not the notification start command transmitted from the master is received. If not received, the process waits until it is received. If received, the process proceeds to step 222.

  In step 222, light intensity information, which is information of light intensity that can be received in common by each PD, is transmitted to the master. In the case of the slave 1, as described above, the light intensity that can be received in common by each PD of the slave 1 is “3” to “6”. Therefore, the light intensity information transmitted to the master includes “3”. ~ '6' is set.

  When each slave executes the above processing, light intensity information is transmitted from each slave to the master. Thereby, in the master, the light intensity that can be received in common in all the PDs of each slave can be set uniformly.

  Of the plurality of PDs provided in each of the slaves 1 to 3, the PD having the highest light intensity that can be normally received is set as the light receiving element for inspection, and the reception status of the set PD is confirmed. Good. For example, in the example of FIG. Second PD has the highest light intensity of “4” that can be received, which is the highest among all PDs. In other words, it can be said that this PD has the lowest reception sensitivity among all PDs, and if the light intensity of the master LD is set in accordance with this PD, it is possible to receive stably by all the PDs of the slave. Become. Therefore, this PD is set as an inspection light-receiving element, and for example, the above-mentioned predetermined pattern signal is periodically transmitted to check the reception result, thereby adjusting the light intensity of the master LD. For example, the slave 2 No. When the minimum receivable light intensity in PD 2 changes from “4” to “5”, the light intensity of the master LD is reset to “5”. Thereby, optical communication can always be performed in a good state.

  Next, operations of the master and the slaves 1 to 3 when setting the light intensity of the LD of the slave will be described with reference to flowcharts shown in FIGS. This process is executed by each device at predetermined time intervals, for example.

  In step 300 shown in FIG. 7, the master optical communication control unit 22 determines whether or not a slave strength adjustment start command transmitted from the electronic circuit 12A as the host device is received. If YES in step 302, the flow advances to step 302.

  In step 302, a NotReady signal indicating that preparation is in progress is transmitted to the electronic circuit 12A to notify that normal data transmission cannot be performed.

  In step 304, the number of nodes S representing the number of slaves connected to the master is set (here, “3” is set), and a variable n representing the number of the slave is initialized (here, “1” is set). To do.

  In step 306, a variable m representing the light intensity is initialized (in this case, “1” is set), and in step 308, a slave intensity adjustment start command is transmitted to the slave n. This command is transmitted at the light intensity if the light intensity is set by the above processing in the master, and is transmitted at the maximum light intensity if the light intensity is not set.

  Since the slave n transmits a response signal indicating whether or not the slave strength adjustment start command has been normally received to the master, the master receives the response signal and performs corresponding processing. Specifically, if the response signal is a signal indicating that the slave n has successfully received the slave strength adjustment start command, the process directly proceeds to step 310 to indicate that the slave n has not been received normally. If it is a signal, the slave intensity adjustment start command is transmitted with the light intensity level lowered by one, and the same processing as described above is performed.

  Such processing is repeated until the slave strength adjustment start command can be normally received on the slave n side. If the slave n cannot normally receive the slave intensity adjustment start command with all the light intensities, an error may be notified to the electronic circuit 12A, and this routine may be terminated.

  For each command to be described later, a slave intensity adjustment start command is transmitted at a light intensity that can be normally received by slave n.

  In step 310, each PD receives a predetermined pattern signal corresponding to the light intensity m transmitted from the master.

  In step 312, it is determined whether or not the predetermined pattern signal received by each PD can be recognized normally. That is, it is determined whether the pattern of the predetermined pattern signal corresponding to the received light intensity m matches the pattern of the predetermined pattern signal corresponding to the light intensity m stored in the memory 23.

  If the received predetermined pattern signal can be recognized normally, the process proceeds to step 314, and “1” is substituted for the variable Hx for substituting the reception result. The process proceeds to step 316, and “0” is substituted for the variable Hx. 'X' indicates a channel number, that is, a PD number.

  In step 318, the slave number n, the light intensity m, the channel number x, and the variable Hx that is the reception result are stored in the memory 23 as reception result information.

  In step 320, the light intensity m is incremented, and in step 322, it is determined whether m is greater than the maximum light intensity (here, “7”). If m is less than or equal to the maximum light intensity, the process returns to step 310 and the same processing is repeated. If m is greater than the maximum light intensity, that is, steps 310 to 320 are performed for predetermined pattern signals of all light intensities. If the above process is performed, the process proceeds to step 324.

  In step 324, an intensity adjustment end command is transmitted to slave n, and in step 326, slave number n is incremented.

  In step 328, it is determined whether or not the slave number n is larger than the slave number S (here, “3”). If n is less than or equal to the number of slaves S, the process returns to step 306 and the same processing is repeated. If n is greater than the number of slaves S, that is, the processes of steps 306 to 326 are performed for all slaves. If so, the process proceeds to step 330.

  In step 330, based on the reception result information stored in the memory 23, the light intensity that can be received in common by each slave PD is extracted for each slave.

  Here, FIG. 9 shows an example of the correspondence 52 between the light intensity of the LD of the slave and the reception result of each PD of the master when a predetermined pattern signal is transmitted from the slave to the master with each light intensity. Note that “◯” in the correspondence relationship 52 indicates that the predetermined pattern of the light intensity has been normally recognized by the master, and “×” indicates that it has not been normally recognized.

  For example, in the example of FIG. 9, in the case of the slave 1, “3” to “6” are extracted as the light intensity that can be commonly received by each PD of the master for the predetermined pattern signal transmitted from the slave 1. In this case, “4” to “7” are extracted as light intensities that can be received in common by each PD of the master for the predetermined pattern signal transmitted from the slave 2, and in the case of the slave 3, the predetermined intensity transmitted from the slave 3 is extracted. For the pattern signal, “2” to “5” are extracted as light intensities that can be received in common by the respective PDs of the master.

  In step 332, it is determined whether or not the light intensity that can be commonly received by each slave PD is extracted in all slaves. If extraction is possible, the process proceeds to step 334. Then, the process proceeds to step 336.

  In step 334, the light intensity of each LD of each slave is set. Specifically, for example, for each slave, the light intensity extracted in step 330 is set to the lowest intensity. In the example of FIG. 9, as indicated by the dotted frame in the figure, “3” for slave 1, “4” for slave 2, and “2” for slave 3 are uniformly set as the light intensity of each LD. . Regarding the light intensity of the master LD, it is preferable to set the light intensity uniformly for all slaves in consideration of the case where there is no time for switching the slave that is the transmission destination. Therefore, it is not necessary to set the light intensity uniformly for all slaves.

  On the other hand, in step 336, since there is no light intensity that can be received in common in each PD of the master for the slave, an error is notified to the electronic circuit 12A.

  In step 338, n is initialized again (here, set to '1'). In step 340, an intensity setting notification command for starting notification of the set light intensity is transmitted to slave n.

  In step 342, the light intensity setting value set for the slave is transmitted to the slave n.

  In step 344, n is incremented, and in step 346, it is determined whether or not the slave number n is larger than the slave number S. If n is less than or equal to the number of slaves S, the process returns to step 340 and the same processing is repeated. If n is greater than the number of slaves S, that is, the processes of steps 340 to 344 are performed for all slaves. If so, the process proceeds to step 348.

  In step 348, a Ready signal indicating that preparation for data communication is completed is transmitted to the electronic circuit 12A.

  Next, processing executed in each slave will be described with reference to a flowchart shown in FIG. This process is executed every predetermined time.

  In step 400, it is determined whether or not the slave strength adjustment start command has been normally received from the master. If the slave strength adjustment start command has been normally received, the process proceeds to step 401 and a response signal indicating normal reception is transmitted to the master and received normally. If not, the routine proceeds to step 418, and after transmitting a response signal indicating abnormal reception to the master, this routine is terminated.

  In step 402, a variable m representing the light intensity is initialized (in this case, “1” is set), and in step 404, a predetermined pattern signal corresponding to the light intensity m is transmitted from any LD of the LD array 18 to the master. To do.

  In step 406, the light intensity m is incremented, and in step 408, it is determined whether m is greater than the maximum light intensity (here, “7”). If m is less than or equal to the maximum light intensity, the process returns to step 404 and the same processing is repeated. If m is greater than the maximum light intensity, that is, steps 404 and 406 are performed for a predetermined pattern signal of all the light intensity. If the above process is performed, the process proceeds to step 410.

  In step 410, it is determined whether or not an intensity adjustment end command transmitted from the master is received. If not received, the process waits until it is received. If received, the process proceeds to step 412.

  In step 412, it is determined whether or not the strength setting notification command transmitted from the master is received. If not received, the process waits until it is received. If received, the process proceeds to step 414.

  In step 414, the light intensity setting value transmitted from the master is received, and in step 416, the received light intensity setting value is set to a driving unit (not shown) that drives the LD.

  When each slave executes the above processing, the light intensity setting value is transmitted from the master to each slave, and the light intensity is set in each slave.

  It should be noted that, among a plurality of PDs provided in the master, a PD having the highest light intensity that can be normally received is set as a light receiving element for inspection, and the reception status of the set PD may be confirmed. For example, in the example of FIG. No. 4 PD has the lowest light intensity that can be received and is the highest among all PDs. In other words, it can be said that this PD has the lowest reception sensitivity among all the PDs, and if the light intensity of the LD of the slave 1 is set according to this PD, the optical signal from the slave 1 is stable with all the PDs of the master. Can be received. Therefore, this PD is set as an inspection light-receiving element, and for example, the above-mentioned predetermined pattern signal is periodically transmitted from the slave 1 to check the reception result, and the light intensity of the LD of the slave 1 is adjusted. For example, the master No. When the minimum receivable light intensity in the PD of 4 changes from “3” to “4”, the LD light intensity of the slave 1 is reset to “4” and the slave 1 is notified. The same applies to the slaves 2 and 3. Thereby, optical communication can always be performed in a good state.

  As described above, in this embodiment, the light intensity that can be received in common by all the PDs of the master is extracted, and the light intensity of the LD of each slave is set therefrom. For this reason, the optimum light intensity can be set regardless of variations in the light amount of the LD, the sensitivity of the PD, the loss of the transmission path, and the like, and good optical communication can be performed.

  Also, in this embodiment, the intensity adjustment of the LD of each slave is not performed for each channel, the light intensity of each channel is set uniformly, and the light intensity of each slave can be received by each PD of the master in common. The minimum light intensity is set. For this reason, the apparatus can have a simple configuration, and the life of the apparatus can be extended while suppressing power consumption.

  In the present embodiment, the case where there are three slaves has been described, but it goes without saying that the number of slaves is not limited to this.

It is a block diagram which shows schematic structure of an optical communication system. 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 flowchart of the process performed by a master, when setting the light intensity of a master. It is a flowchart of the process performed by a slave when setting the light intensity of a master. It is a figure which shows the correspondence of the light intensity of LD of a master, and the reception result in each PD of each slave. It is a flowchart of the process performed by a master in the case of setting the light intensity of a slave. It is a flowchart of the process performed by a slave in the case of setting the light intensity of a slave. It is a figure which shows the correspondence of the light intensity of LD of a slave, and the reception result in each PD of a master.

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, 28, 30, 32, 34, 36, 38, 40 Optical fiber 42 Optical sheet bus

Claims (12)

A plurality of first light-emitting elements and a plurality of first light-receiving elements, each having a first optical fiber for transmission, an optical sheet bus for transmission, and a plurality of other optical communication devices via the plurality of second optical fibers for transmission, respectively In the optical communication device connected to each of the plurality of other optical communication devices via the first receiving optical fiber, the receiving optical sheet bus, and the plurality of second receiving optical fibers,
Transmitting means for transmitting a predetermined pattern signal from each of the plurality of first light emitting elements to each of the plurality of other optical communication devices with a plurality of different light intensities;
Receiving means for receiving, from each of the plurality of other optical communication devices, reception result information when each of the predetermined pattern signals is received by each of the plurality of second light receiving elements included in each of the other optical communication devices;
Setting means for setting light intensities of the plurality of first light emitting elements based on reception result information transmitted from the other optical communication devices;
An optical communication device comprising:   The setting means extracts light intensity that can be normally received in all of the plurality of second light receiving elements respectively provided in the plurality of other optical communication devices based on the reception result information, and out of the extracted light intensity The optical communication apparatus according to claim 1, wherein the predetermined light intensity is uniformly set as the light intensity of the plurality of first light emitting elements.   3. The optical communication apparatus according to claim 2, wherein the predetermined light intensity is the lowest light intensity among the extracted light intensities.   4. The optical communication apparatus according to claim 2, wherein the setting unit notifies the host apparatus when the light intensity that can be normally received cannot be extracted.   Among the plurality of second light receiving elements provided in each of the plurality of other optical communication devices, the second light receiving element having the highest light intensity that can be normally received is set as the light receiving element for inspection, and the set for inspection The optical communication apparatus according to claim 2, further comprising confirmation means for confirming a reception state of the light receiving element. A plurality of first light-emitting elements and a plurality of first light-receiving elements, each having a first optical fiber for transmission, an optical sheet bus for transmission, and a plurality of other optical communication devices via the plurality of second optical fibers for transmission, respectively In the optical communication device connected to each of the plurality of other optical communication devices via the first receiving optical fiber, the receiving optical sheet bus, and the plurality of second receiving optical fibers,
Predetermined pattern signals transmitted at a plurality of different light intensities from any one of the plurality of second light emitting elements included in the other optical communication device are received for each of the plurality of other optical communication devices. Receiving means for
Setting means for setting the light intensity of the plurality of second light emitting elements based on the reception result of the predetermined pattern signal;
Notification means for notifying the set light intensity to each of the plurality of other optical communication devices;
An optical communication device comprising:   The setting means extracts, based on the reception result, for each of the plurality of other optical communication devices, a light intensity that can be normally received by all of the plurality of first light receiving elements. The optical communication apparatus according to claim 6, wherein the light intensity is uniformly set as the light intensity of the plurality of second light emitting elements.   8. The optical communication apparatus according to claim 7, wherein the predetermined light intensity is the lowest light intensity among the extracted light intensities.   9. The optical communication apparatus according to claim 7, wherein the setting unit notifies the host apparatus when the light intensity that can be normally received cannot be extracted.   For each of the plurality of other optical communication devices, among the plurality of first light receiving elements, the first light receiving element having the highest light intensity that can be normally received is set as the light receiving element for inspection, and the set inspection is performed. The optical communication apparatus according to claim 7, further comprising confirmation means for confirming a reception state of the light receiving element for use. A plurality of first light-emitting elements and a plurality of first light-receiving elements, each having a first optical fiber for transmission, an optical sheet bus for transmission, and a plurality of other optical communication devices via the plurality of second optical fibers for transmission, respectively Connected and executed by optical communication devices connected to the other optical communication devices via the first optical fiber for reception, the optical sheet bus for reception, and the plurality of second optical fibers for reception. In the optical communication method,
A predetermined pattern signal is transmitted to each of the plurality of other optical communication devices with a plurality of different light intensities from any one of the plurality of first light emitting elements.
Receiving the reception result information from the plurality of other optical communication devices, respectively, when the predetermined pattern signals are received by the plurality of second light receiving elements respectively provided in the other optical communication devices;
Based on the reception result information transmitted from the other optical communication devices, the light intensity of the first light emitting elements is set.
An optical communication method characterized by the above. A plurality of first light-emitting elements and a plurality of first light-receiving elements, each having a first optical fiber for transmission, an optical sheet bus for transmission, and a plurality of other optical communication devices via the plurality of second optical fibers for transmission, respectively Connected and executed by optical communication devices connected to the other optical communication devices via the first optical fiber for reception, the optical sheet bus for reception, and the plurality of second optical fibers for reception. In the optical communication method,
Predetermined pattern signals transmitted at a plurality of different light intensities from any one of the plurality of second light emitting elements included in the other optical communication device are received for each of the plurality of other optical communication devices. And
Based on the reception result of the predetermined pattern signal, set the light intensity of the plurality of second light emitting elements,
Notifying each of the plurality of other optical communication devices of the set light intensity,
An optical communication method characterized by the above.

Images