JP2012003005A - Optical monitor device and optical signal detection method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an optical monitor device capable of easily visually confirming the transmission state of an optical signal, even when the transmission state of the optical signal is indicated by a sporadic optical signal and to provide an optical signal detection method.SOLUTION: A transmission information holding means 81 holds transmission information being information for showing that the optical signal having power exceeding a previously set threshold is transmitted, when the optical signal is transmitted in an optical transmission path. A display means 82 displays that the optical signal is transmitted on condition that the transmission information is held.

Description

  The present invention relates to an optical monitor device and an optical signal detection method for confirming the presence or absence of an optical signal propagating through an optical fiber.

  In recent years, in the field of communication, optical fibers capable of high-speed and large-capacity transmission have become the mainstream of transmission lines, and the range of use has expanded dramatically. Along with this, particularly in optical communication-related facilities such as data centers and office buildings, construction work such as changing, abolishing, or adding an optical transmission line has been frequently performed. In many cases, the optical intensity of communication light transmitted through such an optical transmission line in an optical communication-related facility is high, and visual confirmation is dangerous. Therefore, in order to improve the maintainability and operational efficiency of the optical communication-related facilities, many means for visually confirming the communication status of the optical transmission line are being studied.

  For example, a communication light detector has been proposed in which an optical fiber is incorporated and a waveguide made of a light-transmitting resin is provided in a gap provided between the end faces of ferrules that are connected together in a split sleeve. In the communication light detector, the presence or absence of transmission of communication light is detected by receiving a part of the communication light guided above the waveguide with a phosphor (for example, see Patent Document 1).

  In addition, an optical waveguide substrate is disposed between two ferrules containing an optical fiber, and the communication light output unit extracts part of the communication light branched by the optical waveguide substrate, thereby confirming the presence or absence of communication light. A method has been proposed (see, for example, Patent Document 2).

  Patent Document 3 describes an optical monitor device that monitors the presence / absence of an optical signal and the transmission direction. The optical monitor device described in Patent Document 3 has a branch film on the branch surface of the optical fiber, and a part of the optical signal reflected by the branch film is detected by a photodiode (hereinafter referred to as PD). Then, a light emitting diode (hereinafter referred to as LED) displays whether or not an optical signal is transmitted in a visible state.

  On the other hand, in a general optical communication device (sometimes called an optical monitor device) to which an optical fiber is connected, a laser beam is used when repairing or performing maintenance work on an optical transmission line. A laser shutdown function is implemented for the purpose of preventing the effects on the human body. This function adjusts the laser output on / off at specific time intervals. In a general optical communication device, while a failure occurs in the optical transmission line, the laser output is adjusted on / off in response to the occurrence of the failure. When the laser output is turned on / off, a burst signal is generated, and transmission / reception of the burst signal is performed in the optical fiber.

  Patent Document 4 describes a signal break detection circuit capable of arbitrarily setting a signal break alarm issuing time for notifying an abnormality when a data signal break to the optical receiver occurs. The signal break detection circuit described in Patent Document 4 counts input data signals per fixed time, and when this count value reaches a predetermined value (a positive integer other than 1), it is determined as abnormal and the signal break is detected. Issue an alarm.

JP 2004-170488 A (paragraphs 0014, 0019, 0020, FIG. 2) JP 2004-133071 (paragraphs 0025, 0028, 0030, FIG. 3) Japanese Patent Laid-Open No. 2002-214487 (paragraphs 0021, 0022, FIG. 1) JP 2003-158497 A (paragraphs 0019, 0020, 0059)

  In a general optical monitor device, the light detector includes a phosphor or PD and a light emitting diode. In general optical monitoring devices, when a safety measure function such as a laser shutdown function (for example, a function to periodically turn on / off the laser output) works, a single optical signal such as a burst signal is generated. However, the time during which the optical signal can be detected is extremely short. In such a case, it is difficult to visually confirm an optical signal whose detection time is extremely short even if the light detection devices and methods described in Patent Documents 1 to 4 are used. There's a problem.

  Therefore, when the safety countermeasure function as described above is working, it is possible to easily grasp the state of whether or not the optical transmission line is used even if the devices and methods described in Patent Documents 1 to 4 are used. Is difficult. For example, there are concerns about human error such as it takes time to grasp the operational state of the optical transmission line, or the optical connector of the used optical transmission line is mistaken for being not used. .

  Specifically, in the optical monitor device described in Patent Document 3, since the optical signal continues to be reflected by the branch film while the optical signal is transmitted, the transmission state of the optical signal can be displayed. However, in the case of a single optical signal such as a burst signal, it is difficult to visually confirm the state because the time during which the optical signal is transmitted can be displayed for a short time.

  In addition, the signal break detection circuit described in Patent Document 4 adjusts the time until the signal break alarm is issued when the signal break of the optical signal is detected. Even if the signal interruption alarm adjusted in this way is transmitted once, it is desirable that the transmission state can be easily confirmed visually.

  Accordingly, an object of the present invention is to provide an optical monitor device and an optical signal detection method capable of easily visually confirming the transmission state even when the transmission state of the optical signal is indicated by a single optical signal. And

  The optical monitor device according to the present invention, when an optical signal having a power exceeding a predetermined threshold is transmitted through the optical transmission path, holds transmission information that is information indicating that the optical signal has been transmitted. And display means for displaying that the optical signal has been transmitted on condition that transmission information is held.

  The optical signal detection method according to the present invention holds transmission information, which is information indicating that an optical signal has been transmitted, when an optical signal having a power exceeding a predetermined threshold is transmitted in the optical transmission path, and transmits the optical signal. It is characterized by displaying that the optical signal has been transmitted on condition that the information is retained.

  According to the present invention, even when the transmission state of an optical signal is indicated by a single optical signal, the transmission state can be easily confirmed visually.

It is explanatory drawing which shows the example of the optical communication system using the optical monitor device in the 1st Embodiment of this invention. It is explanatory drawing which shows the structure of the optical monitor device in 1st Embodiment. It is explanatory drawing which shows the internal structure of the optical monitor device in 1st Embodiment. It is explanatory drawing which shows the example of the optical waveguide board | substrate 1 in 1st Embodiment, and the circuit board 3. In FIG. It is explanatory drawing which shows the example of the optical waveguide board | substrate 1 and the circuit board 3 in 2nd Embodiment. It is explanatory drawing which shows the example of the minimum structure of the optical monitor device by this invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

Embodiment 1. FIG.
FIG. 1 is an explanatory diagram showing an example of an optical communication system using the optical monitor device according to the first embodiment of the present invention. The optical communication system illustrated in FIG. 1 includes optical communication devices 51a and 51b and optical monitor devices 55a-1, 55a-2, 55b-1, and 55b-2. The optical monitor devices 55a-1 and 55a-2 are connected to the optical communication device 51a, and the optical monitor devices 55b-1 and 55b-2 are connected to the optical communication device 51b. The optical monitor device 55a-1 and the optical monitor device 55b-1 and the optical monitor device 55a-2 and the optical monitor device 55b-2 are connected via the optical fiber 2, respectively. In the following description, the optical monitor devices 55a-1, 55a-2, 55b-1, and 55b-2 are collectively referred to as an optical monitor device 55.

  The optical communication device 51a includes a signal processing unit 53a and an optical transmission / reception unit 54a. The optical transceiver 54a receives an optical signal from the optical fiber 2 connected via the optical monitor device 55a-1. Moreover, the optical transmission / reception part 54a transmits an optical signal to the optical fiber 2 connected via the optical monitor device 55a-2.

  Specifically, the optical communication device 51a transmits a signal to be transmitted to the optical communication device 51b (and the devices under its control) to the optical fiber 2. In addition, the optical communication device 51a receives a signal transmitted from the optical communication device 51b (and its subordinate equipment) via the optical fiber 2, and terminates in itself or is connected to the own device. Performs signal transmission processing to other devices.

  The signal processing unit 53 a performs extraction processing, accommodation processing, and the like of the optical signal received from the optical fiber 2 and the optical signal transmitted to the optical fiber 2. As a signal processed by the signal processing unit 53a, for example, an Ethernet (registered trademark) signal defined in IEEE802.3 can be cited. Since the function of the optical communication apparatus is widely known, detailed description thereof is omitted. Also, the optical communication device 51b is the same as the function of the optical communication device 51a, and a description thereof will be omitted.

  In the example shown in FIG. 1, the case where the optical signal devices 51a and 51b include one optical transmission / reception unit is described. However, the number of optical transmission / reception units included in the optical signal devices 51a and 51b is not limited to one. . The device connected to the optical signal device is not limited to the optical signal device. Other types of devices may be connected to the optical signal device.

  The optical monitor device 55 is a device that detects an optical signal. Specifically, the optical monitor device 55 branches the optical signal transmitted through the optical fiber, and emits light in response to the branched light, thereby visually confirming the presence or absence of the optical signal. Hereinafter, the contents of the optical monitor device 55 will be described with reference to FIGS. 2, 3 and 4.

  2A and 2B are explanatory views showing the structure of the optical monitoring device 55 in the present embodiment. FIG. 2A is a plan view, FIG. 2B is a front view, FIG. 2C is a bottom view, and FIG. FIG. 2D is a left side view, and FIG. 2E is a right side view. As illustrated in FIG. 2, the optical monitoring device 55 in the present embodiment includes a male connector 41, a female connector 42, an optical signal output unit 43, a base unit 44, and terminals 5 as external structures. I have.

  FIG. 3 is an explanatory diagram showing the internal structure of the optical monitor device 55 in the present embodiment. As illustrated in FIG. 3, the optical monitor device 55 in the present embodiment includes an optical waveguide substrate 1, a plug frame 11, ferrules 12 and 13, a housing 14, and a split slave 15. Note that the optical waveguide substrate 1 is disposed in the base portion 44 illustrated in FIG. 2 because of its internal structure.

  A male connector 41 illustrated in FIG. 2 is a connector that is fitted and coupled to an optical fiber connector that transmits an optical signal. Further, the plug frame 11 and the ferrule 12 illustrated in FIG. 3 are arranged inside the male connector 41. The female connector 42 illustrated in FIG. 2 is also a connector that is fitted and coupled to an optical fiber connector that transmits an optical signal, like the male connector 41. Further, the housing 14 illustrated in FIG. 3, the split slave 15, and the ferrule 13 are disposed inside the female connector 42.

  The female connector 42 is formed in a shape to which the male connector 41 can be fitted. If the male connector 41 is inserted into the female connector 42, the female connector 42 is fitted and fixed after the plug frame 11 is guided by the housing 14. Then, the ferrule 12 is fitted into the split slave 15 and the ferrule 12 and the ferrule 13 are bonded to form an optical path.

  In the present embodiment, two transmission connectors (specifically, male connector 41 and female connector 42) are arranged in a straight line in pairs. As a transmission connector for the optical fiber, a female connector 42 is provided on the side connected to the male connector 41 of the optical monitor device 55, and a male connector is provided on the side connected to the female connector 42 of the optical monitor device 55. Each of the connectors 41 is employed.

  2 and 3 (more specifically, the male connector 41 and the female connector 42) are specific examples of transmission connectors, and the structure of these connectors is as follows. It is not limited to the shape illustrated in FIGS. The structures of these connectors may be other structures as long as they can be coupled to the optical fiber 2.

  The optical signal output unit 43 illustrated in FIG. 2 displays whether or not an optical signal is transmitted on the optical transmission path in a visible state. As illustrated in FIG. 2, the optical signal output unit 43 is disposed on one plane of the base unit 44. In addition, as illustrated in FIG. 3, the optical signal output unit 43 includes a circuit board 3, a light emitting element 4, and a ferrule 6. The light emitting element 4 emits light according to an instruction from the circuit board 3. The light emitting element 4 is realized by, for example, an LED. The contents of the circuit board 3 will be described later.

  The base portion 44 illustrated in FIG. 2 is for housing and fixing the male connector 41, the female connector 42, the optical signal output portion 43, and the optical waveguide substrate 1 at predetermined positions. For example, the base portion 44 is made of plastic or metal. It is formed.

  The terminal 5 illustrated in FIG. 2 is connected to the optical signal output unit 43 and supplies necessary power to the circuit board 3 from an external power supply device (not shown).

  The optical waveguide substrate 1 illustrated in FIG. 3 functions to branch incident light. The optical waveguide substrate 1 is accommodated in the package 7 of the base portion 44. In addition, ferrules 6, 12, and 13 are connected to the optical waveguide substrate 1 through connection portions 8 and 9, and optical paths 2a, 2b, and 2c are formed so as not to leak light.

  FIG. 4 is an explanatory diagram illustrating an example of the optical waveguide substrate 1 and the circuit substrate 3 in the present embodiment. The optical waveguide substrate 1 is provided with a branching unit 60 so that the light transmitted from the optical path 2a is branched into the optical path 2b and the optical path 2c. Specifically, the branching unit 60 uses an optical path 2a through which an optical signal is transmitted as an optical path 2b (hereinafter also referred to as an optical transmission path) for transmitting light to another device. A branch is made to a monitoring optical path 2c (hereinafter referred to as a monitoring transmission path) for determining whether or not transmission is in progress. The branching unit 60 is realized by, for example, a light transmissive waveguide, a half mirror, an optical waveguide, or the like.

  The branching unit 60 is formed so as to branch the optical signal transmitted from one side but not to branch the optical signal transmitted from the other side. In the example shown in FIG. 4, the optical signal from the optical path 2a is branched into the optical path 2b and the optical path 2c, but the optical signal from the optical path 2b is not branched into the optical path 2c but is transmitted to the optical path 2a. With such a structure, the presence or absence of an optical signal transmitted in a specific direction can be confirmed.

  In the present embodiment, for example, a light transmissive waveguide body, a half mirror, an optical waveguide, or the like is provided as the branch portion 60. By providing these as the branch part 60, maintenance becomes easy. Therefore, it is possible to provide an optical monitor device that is easy to operate and excellent in maintainability.

  The circuit board 3 includes a power supply circuit 61, a latch circuit 62, a comparison circuit 63, and an optical signal receiving circuit 64.

  The optical signal receiving circuit 64 converts an optical signal received through the optical path 2c into a voltage. Specifically, the optical signal receiving circuit 64 includes a PD 641 and a current-voltage conversion circuit 642. The PD 641 receives an optical signal incident from the optical waveguide substrate 1 and converts it into a current corresponding to the intensity of the optical signal. The current-voltage conversion circuit 642 is a circuit that converts the current converted by the PD 641 into a voltage.

  Various materials can be applied to the PD 641 depending on the optical signal to be detected. For example, if visible light is to be detected as an optical signal, germanium may be used as the material of PD641. In addition, in order to detect invisible light as an optical signal, indium, gallium, arsenic, or the like may be used as the material of the PD 641. Thus, by selecting a material according to the type of optical signal to be detected, it is possible to cope with both visible light and invisible light.

  The comparison circuit 63 is a circuit that compares the voltage value converted by the optical signal reception circuit 64 with a predetermined reference voltage value (threshold value). The comparison circuit 63 is realized by, for example, a track and hold circuit. However, the comparison circuit is not limited to the track and hold circuit. Other circuits may be used as long as the voltage value can be compared with a predetermined reference value.

  The latch circuit 62 latches the voltage value based on the comparison result of the comparison circuit 63. Specifically, when the comparison circuit 63 determines that the voltage value has exceeded the threshold value, the latch circuit 62 latches the voltage value. If this threshold value is adjusted to a low value, the voltage value can be latched even for a low-power optical signal.

  The power supply circuit 61 controls the external power feeding from the terminal 5 to light the light emitting element 4. Specifically, when the latch circuit 62 latches the voltage value, the power supply circuit 61 performs switching control of external power feeding from the terminal 5 and turns on the light emitting element 4.

  Thus, since the latch circuit 62 latches the input information of the optical signal, the power supply circuit 61 continues the optical signal output unit 43 (specifically, the light emitting element 4) when the optical signal is transmitted. Can be emitted. Therefore, for example, even a single optical signal such as a burst signal propagating in the optical transmission line can be easily confirmed visually.

  The latch circuit 62 turns off the light emission of the light emitting element 4. Hereinafter, the function of turning off the light emission of the light emitting element 4 is referred to as a reset function. Specifically, a signal for operating the reset function (hereinafter referred to as a reset signal) is separately defined, and a circuit for performing an operation (reset operation) for clearing latched information by the reset signal is incorporated in the latch circuit 62. Leave in. As a circuit that performs the reset operation, for example, an RS flip-flop can be given. By incorporating such a circuit, the light emission time can be arbitrarily adjusted.

  If the reset function is not incorporated in the latch circuit 62, for example, after the optical fiber is removed, the light-emitting element 4 that has been lit once continues to be lit even if there is no optical signal in the optical fiber. Become.

  According to the present embodiment, by incorporating a reset function into the latch circuit 62, the latch circuit 62 releases the latched information at a predetermined time interval. Therefore, since the light emitting element 4 can be intentionally or periodically turned off, the light emission time of the light emitting element 4 can be arbitrarily adjusted. For example, by adjusting the light emission time to the burst signal transmission interval of the optical communication device at the time of laser shutdown, it becomes possible to more appropriately observe the presence or absence of the optical signal.

  Next, the operation will be described. In the following description, the operation of the optical monitor device 55a-1 when an optical signal is transmitted from the optical communication apparatus 51b illustrated in FIG. 1 to the optical communication apparatus 51a will be described.

  The optical signal output from the optical communication device 51b and propagated through the optical fiber 2 enters the optical path 2a illustrated in FIG. Part or all of the incident optical signal is output to the optical path 2b through the optical waveguide substrate 1, and the remaining signal light is output to the optical path 2c. That is, the optical waveguide substrate 1 (more specifically, the branching unit 60) branches the optical signal into two at a predetermined intensity ratio.

  Here, the optical path 2c is a monitoring transmission path for detecting light. Therefore, the intensity of the optical signal transmitted through the optical path 2c is reduced (for example, the intensity ratio of the branched optical signal is “light intensity of the optical path 2b: light intensity of the optical path 2c = 0.95: 0.05”). The branching unit 60 may be designed in advance. By designing the branching unit 60 in this way, the optical signal output from the optical communication device 51b is output from the male connector 41 illustrated in FIG. 2 with almost no attenuation. Accordingly, it is possible to avoid a situation in which communication quality is hindered by attenuation.

  Since the branching unit 60 has the characteristics as described above, the optical signal transmitted to the optical path 2b can be changed by designing the branching unit 60 so as to increase the intensity ratio of the optical signal transmitted to the optical path 2c. It can also be intentionally attenuated. Hereinafter, a specific example will be described.

  For example, when the power of the optical signal incident on the optical path 2a is “1”, the relationship of (power of the optical signal transmitted to the optical path 2b) + (power of the optical signal transmitted to the optical path 2c) = “1” The formula holds. In the following description, the power of the optical signal transmitted to the optical path 2b is referred to as power 2b, and the power of the optical signal transmitted to the optical path 2c is referred to as power 2c. For example, when the intensity ratio between the power 2b and the power 2c is 0.5: 0.5 (hereinafter referred to as scene 1), an optical signal having the same power “0.5” is transmitted to the optical path 2b and the optical path 2c. Will flow.

  Next, the case where the intensity ratio between the power 2b and the power 2c is 0.1: 0.9 (hereinafter referred to as scene 2) will be described as an example. In this case, an optical signal with power “0.1” flows through the optical path 2b, and an optical signal with power “0.9” flows through the optical path 2c. Therefore, when viewed from the optical communication apparatus 51b, the situation of the scene 2 is smaller (attenuated) than the intensity of the optical signal reaching the optical communication apparatus 51a as compared to the situation of the scene 1. Thus, as the intensity ratio of the power 2c to the power 2b is increased, the power of the optical signal transmitted through the optical path 2b is decreased.

  On the other hand, as the intensity ratio of the power 2c to the power 2b is reduced, the attenuation of the optical signal reaching the optical communication device 51a can be suppressed. For example, when the intensity ratio between the power 2b and the power 2c is 0.999: 0.001 (hereinafter referred to as scene 3), an optical signal of power “0.999” flows in the optical path 2b, and the optical path An optical signal with power “0.001” flows through 2c. In scene 3, it can be said that the intensity of the optical signal transmitted from the optical communication device 51b is not substantially attenuated in the optical signal reaching the optical communication device 51a.

  Next, the optical signal branched to the optical path 2c enters the circuit board 3 through the ferrule 6 illustrated in FIG. In the circuit board 3, the PD 641 receives the incident optical signal and generates a current corresponding to the intensity of the received optical signal. An amplifier (not shown) may amplify this current.

  Thereafter, the current-voltage conversion circuit 642 converts the generated current into a voltage. Then, the comparison circuit 63 compares the threshold value with the converted voltage value as a reference value. When the voltage value exceeds the reference voltage, the latch circuit 62 latches the voltage value. The power supply circuit 61 turns on the light emitting element 4 by switching control of external power feeding from the terminal 5 based on the latched information. Thus, since the latch circuit 62 latches the input information (here, the voltage value) of the optical signal, when the optical signal is transmitted, the power supply circuit 61 causes the optical signal output unit 43 (shown in FIG. 2). More specifically, the light emitting element 4) can continuously emit light. For this reason, for example, the presence or absence of a single optical signal such as a burst signal propagating in the optical transmission path can be easily confirmed visually.

  The latch circuit 62 intentionally or periodically turns off the light emitting element 4 in accordance with the transmission interval of the burst signal transmitted from the optical communication device at the time of laser shutdown. Thus, by adjusting the light emission time, it is possible to appropriately visually check the presence or absence of an optical signal.

  When an optical signal is transmitted from the optical communication device 51b illustrated in FIG. 1 to the optical communication device 51a, the optical monitor device 55b-1 transmits an optical signal from the optical path 2b illustrated in FIG. . Also in this case, the incident optical signal is input to the optical waveguide substrate 1. However, the incident optical signal is transmitted to the optical path 2a without being branched. That is, in the optical monitor device 55b-1, the light emitting element 4 is not turned on because there is no optical signal propagating in the direction of the optical path 2c illustrated in FIG. Therefore, the presence or absence of light transmission in a specific direction can be confirmed by confirming the light emission of the light emitting element 4.

  As described above, according to the present embodiment, when the comparison circuit 63 determines that the optical signal converted into the voltage value exceeding the predetermined threshold value has been transmitted through the optical path 2c, the latch circuit 62 performs the transmission. A voltage value is held as information indicating that the operation has been performed. Then, on condition that the latch circuit 62 holds the voltage value, the power supply circuit 61 turns on the light emitting element 4 to display that the optical signal has been transmitted. Therefore, even when the transmission state of an optical signal is indicated by a single optical signal, such as a burst signal, the transmission state can be easily confirmed visually.

  Specifically, the branching unit 60 branches the optical path of the optical signal. Then, the optical signal receiving circuit 64 (more specifically, the PD 641) takes out the branched monitoring optical signal and converts the optical signal into an electrical signal. The latch circuit 62 latches information indicating the presence / absence of an optical signal according to the comparison result of the comparison circuit 63. Thus, even when the time for receiving the optical signal is short, the light emission time of the light emitting element 4 can be extended.

  Furthermore, various effects can be expected by using the optical waveguide substrate 1 in a portion where the monitoring optical signal is branched from the optical transmission path (specifically, the optical path 2a). By using the optical waveguide substrate 1, for example, the bending radius is not limited as in an optical fiber coupler, so that the degree of freedom in design can be increased. In addition, since the target for adjusting the optical path is only the ferrule-to-optical waveguide substrate 1, work such as adjustment of the optical system is not necessary. Furthermore, since stable branching of the optical signal can be ensured, monitoring of the optical communication signal can be made more reliable.

  Further, in the present embodiment, a light transmissive waveguide body, a half mirror, an optical waveguide, or the like is provided as the branch portion 60. By providing these as the branch part 60, maintenance becomes easy. Therefore, it is possible to provide an optical monitor device that is easy to operate and excellent in maintainability. In addition, by improving the maintainability and operational efficiency of the optical communication-related equipment, it is possible to expect effective use of unused optical transmission lines in the optical communication-related equipment.

Embodiment 2. FIG.
Next, an optical monitor device according to a second embodiment of the present invention will be described. The optical monitor device according to the first embodiment uses the electric circuit (specifically, the track and hold circuit as the comparison circuit 63, the latch circuit 62) after the PD 641 receives the optical signal, and the light emitting element 4 The light emission time of (specifically, LED) was adjusted. The optical monitor device in the second embodiment is different from the first embodiment in which the PD 641 or the like is used in that the light emission time of the light emitting element is adjusted using an optical thyristor as a light receiving element. About another structure, it is the same as that of 1st Embodiment.

  Hereinafter, an example of an optical communication system using the optical monitor device according to the second embodiment will be described with reference to FIG. Further, the structure of the optical monitor device is the same as the contents illustrated in FIGS.

  FIG. 5 is an explanatory diagram illustrating an example of the optical waveguide substrate 1 and the circuit substrate 3 in the present embodiment. The contents of the optical waveguide substrate 1 are the same as those of the optical waveguide substrate 1 in the first embodiment.

  The circuit board 3 in this embodiment includes an optical thyristor 65. An anode (not shown) of the optical thyristor 65 is connected to the terminal 5, and a canode (not shown) of the optical thyristor 65 is connected to the light emitting element 4. The optical thyristor 65 has a characteristic that current flows from the anode to the canode when the power of the optical signal incident on the gate exceeds a certain threshold value. The optical thyristor 65 has a characteristic that once an optical signal with a power exceeding the threshold is received, a current is continuously passed from the anode to the canode even if there is no optical signal incident on the gate. That is, it can be said that the optical thyristor 65 holds information indicating that the optical signal has been transmitted. Therefore, when an optical signal having a power exceeding a certain threshold is input from the optical path 2c, the optical thyristor 65 continuously causes the light emitting element 4 connected to the canode to emit light.

  In addition, the circuit board 3 includes a circuit (not shown; hereinafter referred to as a light emission control unit) having a function of turning off the light emission of the light emitting element 4 (that is, a reset function). Specifically, the light emission control unit cuts off the current to the anode at a predetermined interval. For example, the light emission control unit may block the current to the anode by switching the current using a transistor or an IC provided on the circuit board 3. By providing such a circuit, the light emission time can be arbitrarily adjusted. In the above description, the case where the light emission control unit provided on the circuit board 3 interrupts the current has been described. In addition, power supply from the terminal 5 may be cut off by external control.

  If the circuit board 3 does not have a reset function, for example, after the optical fiber is removed, even if the optical signal does not exist in the optical fiber, the light emission that is once turned on is the same as in the first embodiment. Element 4 will continue to be lit. In such a case, it is difficult to say that the optical monitor device 55 accurately reflects the state of the current optical signal transmitted through the optical fiber.

  However, according to the present embodiment, by providing the circuit board 3 with the reset function (light emission control unit), the light emission control unit blocks the current to the anode at a predetermined time interval. Therefore, since the light emitting element 4 can be intentionally or periodically turned off, the light emission time of the light emitting element 4 can be arbitrarily adjusted. For example, by adjusting the light emission time to the burst signal transmission interval of the optical communication device at the time of laser shutdown, it becomes possible to more appropriately observe the presence or absence of the optical signal.

  Next, the operation will be described. In the following description, as in the first embodiment, the operation of the optical monitor device 55a-1 when an optical signal is transmitted from the optical communication apparatus 51b illustrated in FIG. 1 to the optical communication apparatus 51a will be described.

  Similar to the first embodiment, the optical signal output from the optical communication device 51b and propagated through the optical fiber 2 enters the optical path 2a illustrated in FIG. Part or all of the incident optical signal is output to the optical path 2b through the optical waveguide substrate 1, and the remaining signal light is output to the optical path 2c.

  The optical signal branched to the optical path 2c enters the circuit board 3 through the ferrule 6 illustrated in FIG. In the circuit board 3, the optical thyristor 65 receives the optical signal incident through the optical path 2c at the gate. When the power of the received optical signal exceeds a certain threshold value, a current flows from the anode (not shown) of the optical thyristor 65 to the canode (not shown). The light emitting element 4 is turned on in response to the current.

  As described above, once the optical thyristor 65 receives an optical signal having a power exceeding the threshold value, the optical thyristor 65 continues to flow a current from the anode to the canode even if there is no optical signal incident on the gate. Therefore, the light emitting element 4 connected to the canode continuously emits light. As described above, when the optical signal to be detected is transmitted, the light emission of the optical signal output unit 43 illustrated in FIG. 2 (more specifically, the light emitting element 4 in FIG. 5) can be confirmed. Therefore, for example, the presence or absence of a single optical signal such as a burst signal propagating in the optical transmission path can be easily confirmed visually.

  When an optical signal is transmitted from the optical communication device 51b illustrated in FIG. 1 to the optical communication device 51a, the optical monitor device 55b-1 transmits an optical signal from the optical path 2b illustrated in FIG. . Also in this case, the incident optical signal is input to the optical waveguide substrate 1 as in the first embodiment. However, the incident optical signal is transmitted to the optical path 2a without being branched. That is, in the optical monitor device 55b-1, the light emitting element 4 is not turned on because there is no optical signal propagating in the direction of the optical path 2c illustrated in FIG. Therefore, the presence or absence of light transmission in a specific direction can be confirmed by confirming the light emission of the light emitting element 4.

  As described above, in this embodiment, since the optical thyristor 65 is used, in addition to the effects of the first embodiment, the circuit to be mounted can be simplified. In addition, the number of parts of the optical monitor device 55 can be reduced.

  The configuration used in the first embodiment and the second embodiment is summarized as described above. First, in the optical monitor device 55, the branching unit 60 and the optical transmission path that propagates the optical signal are taken out. The optical transmission line is branched to a monitoring transmission line that propagates some optical signals. Next, the optical signal propagating through the monitoring transmission path passes through, for example, a latch circuit constituted by the PD 641 and the optical flip-flop (latch circuit 62) or the optical thyristor 65. When the optical signal passes through such a latch circuit, the optical monitor device 55 can latch information that the optical signal has propagated at a certain threshold. By using the latched information, it is possible to intentionally extend the light emission time of a means (for example, a light emitting element 4 such as a light emitting diode) for indicating that an optical signal is propagated. Therefore, the presence or absence of signal light propagating in the fiber can be easily confirmed with the naked eye.

  In addition, although the content of this invention was demonstrated using 1st Embodiment and 2nd Embodiment, unless it exceeds the meaning of this invention, it is not limited to this embodiment at all. Further, the shape of the transmission connector and the type of optical fiber exemplified in FIGS. 2, 3 and 4 are not limited to the above-described contents.

  Next, an example of the minimum configuration of the optical monitor device according to the present invention will be described. FIG. 6 is an explanatory diagram showing an example of the minimum configuration of the optical monitor device according to the present invention. The optical monitor device according to the present invention, when an optical signal having a power (for example, a voltage value) exceeding a predetermined threshold is transmitted in the optical transmission path (for example, the optical fiber 2 or the optical path 2c), the optical signal is Transmission information holding means 81 (for example, circuit board 3) that holds transmission information (for example, voltage value) that is information indicating that transmission has been performed, and an optical signal has been transmitted on condition that the transmission information is held The display means 82 (for example, the power supply circuit 61, the light emitting element 4) which displays this (for example, lights up the light emitting element 4) is provided.

  With such a configuration, even if the transmission state of the optical signal is indicated by a single optical signal, the transmission state can be easily confirmed visually.

  Further, the transmission information holding unit 81 (for example, the latch circuit 92, the light emission control unit) holds the transmission held at the interval at which the optical signal is transmitted (for example, the transmission interval of the burst signal transmitted from the optical communication apparatus at the time of laser shutdown). Information may be initialized. By doing in this way, it becomes possible to confirm the presence or absence of an optical signal appropriately.

  Further, branching means for branching an optical signal transmitted through the optical transmission path (for example, the optical path 2a) (for example, to the optical path 2b and the optical path 2c) may be provided. The transmission information holding unit 81 may hold the transmission information when the power of one optical signal branched by the branching unit (for example, the optical signal transmitted through the optical path 2c) exceeds a predetermined threshold. .

  Specifically, the transmission information holding unit 81 includes an optical signal detection unit (for example, PD641) that detects an optical signal to be transmitted, and a voltage conversion unit (for example, a current-voltage conversion circuit 642) that converts the optical signal into a voltage. Comparison means for determining whether or not the voltage value exceeds a predetermined threshold value (for example, the comparison circuit 63), and when the voltage value exceeds a predetermined threshold value, the voltage value is held Voltage value holding means (for example, a latch circuit 62) may be included. The display unit 82 may display that the optical signal has been transmitted on the condition that the voltage value holding unit holds the voltage value. In this case, the optical signal detection means may be a photodiode (for example, PD using indium, gallium, arsenic, etc.) that detects invisible light as an optical signal.

  Alternatively, the transmission information holding unit 81 may hold a state in which a current from an external power source to be connected is supplied to the display unit when an optical signal having a power exceeding a predetermined threshold is transmitted through the optical transmission line. Good. Specifically, the transmission information holding unit 81 may be an optical thyristor (for example, an optical thyristor 65).

  The present invention is preferably applied to an optical monitor device that confirms the presence or absence of an optical signal propagating through an optical fiber.

DESCRIPTION OF SYMBOLS 1 Optical waveguide board | substrate 2 Optical fiber 2a, 2b, 2c Optical path 3 Circuit board 4 Light emitting element 5 Terminal 6, 12, 13 Ferrule 7 Package 8, 9, 10 Connection part 11 Plug frame 14 Housing 15 Split sleeve 41 Male connector 42 Female Connector 43 Optical signal output unit 44 Base unit 51a, 51b Optical communication device 53a, 53b Signal processing unit 54a, 54b Optical transmission / reception unit 55, 55a-1, 55b-1, 55a-2, 55b-2 Optical monitor device 60 Branch Unit 61 Power supply circuit 62 Latch circuit 63 Comparison circuit 64 Optical signal reception circuit 641 PD
642 Current-voltage conversion circuit 65 Optical thyristor

Claims (9)

Transmission information holding means for holding transmission information that is information indicating that the optical signal has been transmitted when an optical signal having a power exceeding a predetermined threshold is transmitted in the optical transmission path;
An optical monitor device comprising: a display unit that displays that the optical signal is transmitted on condition that the transmission information is held. The optical monitor device according to claim 1, wherein the transmission information holding means initializes transmission information held at intervals at which optical signals are transmitted. A branching means for branching an optical signal transmitted in the optical transmission line;
The optical monitor device according to claim 1 or 2, wherein the transmission information holding unit holds transmission information when the power of one optical signal branched by the branching unit exceeds a predetermined threshold value. Transmission information holding means
An optical signal detection means for detecting an optical signal to be transmitted;
Voltage converting means for converting the optical signal into a voltage;
Comparison means for determining whether the value of the voltage exceeds a predetermined threshold;
Voltage value holding means for holding the voltage value when the voltage value exceeds a predetermined threshold value,
The display means displays that an optical signal has been transmitted on the condition that the voltage value holding means holds the voltage value. 4. Optical monitor device. The optical monitor device according to claim 4, wherein the optical signal detection means is a photodiode that detects invisible light as an optical signal. The transmission information holding unit holds information for supplying a current from an external power source to be connected to the display unit when an optical signal having a power exceeding a predetermined threshold is transmitted through the optical transmission line. Item 4. The optical monitor device according to any one of Items 3 to 3. The optical monitor device according to claim 1, wherein the transmission information holding unit is an optical thyristor. When an optical signal having a power exceeding a predetermined threshold is transmitted in the optical transmission path, holding transmission information that is information indicating that the optical signal has been transmitted,
An optical signal detection method comprising displaying that the optical signal has been transmitted on condition that the transmission information is retained. The optical signal detection method according to claim 8, wherein transmission information held at intervals at which optical signals are transmitted is initialized.

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