JP2011059075A - Optical core fiber identification device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical core fiber identification device capable of performing more precise optical core fiber identification without receiving an effect of external disturbance light. <P>SOLUTION: The optical core fiber identification device includes: an optical core fiber identification head 20 in which a curved part for leaking a light signal by partly bending the optical fiber is formed; and a body 10 detachably mounted with the optical core fiber identification head 20. The body 10 includes: a light receiving element holding part 5 holding a first light receiving element and a second light receiving element at both sides in the vicinity near a tip center where a recessed part engaged with the curved part of the optical core fiber identification head 20 is formed; an operation lever 3 moving the light receiving element holding part 5 to the body part 10; and an external disturbance light sensor 1a detecting the light entering the inside of the device from the outside. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an optical fiber core discrimination device used for communication cables and the like.

  In laying an optical cable or the like, in order to measure the optical loss of a plurality of optical fiber cores housed in the cable, it is necessary to identify and identify the optical fiber core wires. In order to discriminate the optical fiber core, a specific optical signal (for example, an optical signal modulated to a frequency of 270 Hz) is usually sent from one end of the optical cable, and light reception is detected by the light receiving element on the other end side. Then, the determination is made by the detection circuit.

  Japanese Patent Application Laid-Open No. H10-228561 describes an optical fiber identification device. This optical core discriminating apparatus includes an optical core discriminating head formed with a curved portion for leaking an optical signal from an optical fiber, and an optical power measuring head provided with a receptor portion to which the optical fiber is detachably attached. And a main body portion on which any one of the heads is detachably mounted. The main body portion includes a light receiving element holding portion that holds the first and second light receiving elements on both sides of the distal end portion that is fitted to the bending portion, and an operation lever that moves the light receiving element holding portion relative to the main body portion. When the optical core discriminating head is mounted on the main body, the light direction is discriminated by detecting the leakage light of the optical fiber using any two light receiving elements.

JP 2005-214663 A

  According to the core discriminating device described in Patent Document 1, the optical direction discriminating function for the optical core wire is realized by using two light receiving elements.

  However, in order to perform accurate optical fiber identification, it is necessary to avoid the influence of disturbance light such as sunlight or illumination light that enters the optical fiber. Since the optical fiber identification device does not have a function of detecting disturbance light, the presence or absence of disturbance light has to be determined by the operator's sense. Therefore, since it may occur that the optical fiber is discriminated in the presence of disturbance light, there is a problem that the apparatus makes an erroneous determination in such a case.

  The present invention has been made in view of the above situation, and an object thereof is to provide an optical core discriminating apparatus which can perform more accurate optical core discriminating without being affected by disturbance light. To do.

  In order to solve the above-described problems, an optical fiber identification device according to the present invention includes an optical fiber identification head formed with a bending portion for partially bending an optical fiber to leak an optical signal, and an optical fiber And a main body for detachably mounting the discrimination head. The main body includes a light receiving element holding means for holding the first light receiving element and the second light receiving element on both sides in the vicinity of the center of the front end where the concave portion to be fitted to the curved portion of the optical fiber identification head is formed. A moving means for moving the element holding means relative to the main body and an external light detecting means for detecting light entering the inside of the optical core discriminating apparatus from the outside.

  According to the present invention, since disturbance light can be detected and notified to an operator, it is possible to perform more accurate optical core line determination without being affected by disturbance light.

It is a perspective view which shows an example of the external appearance of the optical fiber identification apparatus which concerns on this invention. It is a figure which shows the principal part detailed example of the optical-core-line discrimination apparatus equipped with the optical-core-line discrimination head. It is a block diagram which shows the structural example of the detection circuit of the optical-core-line discrimination | determination apparatus to which this invention is applied. It is a block diagram which shows the other example of a structure of the detection circuit of the optical fiber identification device to which this invention is applied.

  FIG. 1 is a perspective view showing an example of the external appearance of the optical fiber identification device according to the present invention. FIG. 1A is a perspective view showing a state in which the optical core discriminating head of the optical core discriminating apparatus is mounted, and FIG. 1B is a state in which the optical core discriminating head of the optical core discriminating apparatus is removed. FIG. FIG. 1C is a partial cross-sectional view around the head mounting confirmation switch in the head mounting state. In the figure, 10 is a main body portion of the optical fiber identification device, 20 is an optical fiber identification head that can be attached to and detached from the main body portion 10, and the optical fiber identification head 20 protrudes toward the main body 10 side. A semicircular curved portion 21 is provided, and the curved portion 21 is provided with a guide groove (not shown) for storing the optical fiber by bending it.

  1A and 1B, a main body 10 includes an upper housing 1, a lower housing 2, an operation lever corresponding to a moving means that can slide relative to the main body 10, and a display 4 such as an LCD. , A light receiving element holding portion 5 corresponding to a light receiving element holding means in which a semicircular recess that fits into the curved portion 21 of the optical fiber identification head 20 is formed. The light receiving element holding portion 5 holds two light receiving elements, and a light shielding plate 6 is integrally provided. The tip of the main body 10 is always urged toward the head mounting protrusion 7 that fits into the groove 22 provided on the optical fiber identification head 20 side, and to the optical fiber identification head 20 side (front). A head mounting confirmation switch 8 that protrudes a certain amount from the head mounting protrusion 7 when the head is not mounted is provided. Here, the groove 22 and the head mounting projection 7 have a dovetail structure, for example.

  The light receiving element holding portion 5 moves relative to the main body portion 10 together with the light shielding plate 6 in conjunction with the operation lever 3 by pushing the operation lever 3 forward (in the direction of the arrow in the figure), and has a concave tip portion. All the light receiving elements held in the position stop at a position facing the curved portion 21 of the optical fiber identification head 20. As a result, the optical core discriminating apparatus enters an operating state and can perform optical core discriminating.

  From the state shown in FIG. 1 (B), when the optical fiber identification head 20 is attached to the main body 10 as shown in FIG. 1 (A), first, in the groove 22 of the optical fiber discrimination head 20, The head mounting projection 7 is fitted from the side surface side of the main body 10, and the optical fiber identification head 20 is attached to the main body 10 by sliding in a parallel (horizontal) direction. At this time, the head mounting confirmation switch 8 is pushed into the main body 10 side by the groove 22. As shown in FIG. 1C, the optical fiber identification head 20 has a recess 23 for receiving the tip of the head mounting confirmation switch 8, and the tip of the head mounting confirmation switch 8 is fitted into the recess 23. Then, the state where the head mounting confirmation switch 8 is pushed into the main body 10 side is released. Thereby, it is recognized that the optical fiber identification head 20 is attached, and the optical fiber identification mode is automatically set.

  Next, after setting the optical fiber at a predetermined position of the optical fiber identification head 20, the operation lever 3 is slid forward to move the light receiving element holding part 5 and the light shielding plate 6 relative to the main body part 10. Let it be in the operating state. When the operating state is reached, external light is shielded, and leakage light from the optical fiber that is bent by the bending portion 21 of the optical fiber core discrimination head 20 is detected by at least two light receiving elements. The detected leaked light is amplified and discriminated by a detection circuit provided in the main body unit 10, and the result is displayed on the display unit 4 or the like.

  In the case of the optical core discriminating apparatus having the above configuration, since the head side is fixed and the light receiving element holding unit side is moved, there is no fear that tension is applied to the optical fiber side in the operation state. There will be no damage.

  An object of the optical fiber identification device according to the present invention is to perform more accurate optical fiber detection without being affected by disturbance light. As a configuration for this, in FIG. 1, the main body unit 10 includes a disturbance light sensor 1 a corresponding to an external light detection unit that detects light entering the inside of the apparatus from the outside. As this disturbance light sensor 1a, for example, an optical sensor such as a photodiode can be used. Moreover, as an arrangement | positioning location of the disturbance light sensor 1a, it can provide in the upper surface of the upper housing | casing 1, as shown in figure, for example.

  The main body 10 has a function of measuring the amount of light detected by the ambient light sensor 1a. A threshold is set for the amount of light, and when the threshold is exceeded, it is determined that ambient light is present. May be. As a method of determining the threshold value, for example, it is conceivable to measure in advance a light amount level (upper limit value) that does not affect optical core discrimination, and set this value as the threshold value.

  Moreover, the main-body part 10 is provided with the notification means to notify a user (operator) of that, when light is detected by the disturbance light sensor 1a. As this notification means, for example, the display unit 4 or a buzzer (see FIGS. 3 and 4 described later) can be considered. As a result, when disturbance light is detected during optical core line discrimination, the operator can be notified by displaying a message on the display unit 4 or making an alarm sound with a buzzer. It is possible to prevent erroneous determination in line determination. In this case, measurement can be performed with higher reliability by performing measurement in a state where disturbance light to the head portion and the nearby fiber portion is shielded.

  FIG. 2 is a diagram showing a detailed example of the main part of the optical fiber discriminating apparatus equipped with the optical fiber discriminating head 20. 2A is a diagram showing a configuration example of the periphery of the head composed of the optical fiber identification head 20 and the light receiving element holding unit 5, and FIG. 2B is an optical fiber identification head 20 and the light receiving element holding unit. 5 is a diagram showing another example of the configuration around the head composed of 5. FIG. In the figure, 24 is an optical fiber core wire.

  When the disturbance light is not detected by the disturbance light sensor 1a, it is considered that the optical fiber can be discriminated. In this case, the operator sets the optical fiber core 24 on the optical core discriminating head 20, and then slides the operating lever 3 forward to move the light receiving element holding portion 5 in the head direction. Thereby, the optical fiber core wire 24 is fixed in a state of being sandwiched between the light receiving element holding portion 5 of the main body portion 10 and the bending portion 21 of the optical core wire identification head 20.

  As shown in FIG. 2A, a first light receiving element (hereinafter referred to as PD1) and a second light receiving element (hereinafter referred to as “PD1”) are provided on both sides (left and right in the figure) of the recess formed at the tip of the light receiving element holding portion 5. PD2) is disposed, approaches the optical fiber core 24 bent by the bending portion 21, and detects and detects the leaked light from the optical fiber core 24. The light level leaked from the optical fiber core 24 is the largest leaked light detected at the first bend, and PD1> PD2 in the optical direction in the figure, so the light level of the leaked light in the two light receiving elements. The light direction can be detected by comparing. For more accurate determination of the light direction, it is preferable that the difference in the light level of the leakage light between the two light receiving elements is larger. In this embodiment, it is preferable to detect the light levels of PD1 and PD2.

  As another example, in the case of modulated light, the phase difference between the two light receiving elements may be seen by detecting the phase instead of the light level of the leaked light. Furthermore, the direction determination may be performed by detecting both the light level and the phase of the leaked light. Thereby, it is possible to determine the light direction with higher accuracy.

In FIG. 2B, a wavelength selection filter 9 is detachably mounted on the light receiving surface side of the light receiving element. The other structures are the same as the structure shown in FIG. 2A, and a description thereof is omitted here.
In this example, the leakage light of the optical fiber core wire 24 is received through the wavelength selection filter 9 on the light receiving surface side of the light receiving element. As the wavelength selection filter 9, for example, various filters such as a dielectric multilayer film can be used. By disposing the wavelength selection filter 9 on the light receiving surface side of the light receiving element or the like, it becomes possible to detect only an optical signal having a specific wavelength that leaks at the curved portion 21. That is, in wavelength multiplexing communication, it is possible to detect the presence or absence of an optical signal in a specific wavelength band. The light receiving element on which the wavelength selection filter is arranged may be PD1 or PD2, or may be arranged on both.

  Generally, a wavelength band of 1.5 μm or 1.3 μm with a small optical transmission loss is used for a communication optical fiber core for signal transmission. In the case of an optical fiber having a wavelength of 1.5 μm, bending to a small diameter is not preferable and requires careful handling. However, in the case of an optical fiber having a wavelength of 1.3 μm, 1.5 μm Compared to the case of the wavelength, the loss increase is not large, and it can be handled relatively roughly with respect to the small-diameter bending. When laying an optical fiber core or the like, it is necessary to grasp these characteristics and handle the optical fiber core. However, it is assumed that the wavelength band of the optical fiber core to be used is unknown. In such a case, the optical fiber identification device of the present invention can also be applied. For example, by using a wavelength selection filter that passes a wavelength band of 1.5 μm or more, it is possible to easily determine whether the optical fiber core is 1.5 μm or more. That is, since the wavelength band of 1.5 μm or more is allowed to pass and the wavelength band of less than that is cut off, it is understood that the optical fiber core wire of 1.5 μm or more is passed.

  Further, for example, wavelength selection filters 9 having different wavelength ranges may be provided on the light receiving surface side of the light receiving elements of PD1 and PD2. Thereby, for example, different wavelengths can be detected by PD1 and PD2. In this case, a switching means for performing detection switching of different wavelengths is provided on the detection circuit side of the main body unit 10 so that optical signals of two different wavelengths can be discriminated and the presence / absence of the optical signal can be checked. it can. Two or more light receiving elements (PD) may be provided, and wavelength selective filters having different selection wavelengths are arranged in each light receiving element, and detection switching is performed, so that the wavelength multiplexed optical transmission line can be changed. It is also possible to select an optical signal in a specific wavelength band from among them and check the presence or absence of the optical signal.

  When the optical fiber identification head 20 is mounted on the main body 10, a protrusion is provided in the mounting surface parallel (horizontal) direction on the optical fiber identification head 20 side, and the mounting surface parallel (horizontal) on the main body 10 side. ) May be configured to provide a groove in the direction. In other words, the groove 22 provided on the optical fiber identification head 20 may be a protrusion, and the head mounting protrusion 7 provided on the main body 10 may be a groove so that the concavities and convexities are reversed.

  FIG. 3 is a block diagram showing a configuration example of a detection circuit of the optical fiber identification device to which the present invention is applied. In the figure, reference numerals 11a and 11b denote amplification units for amplifying electric signals from PD1 and PD2, and 12a and 12b. Is an A / D converter that converts digital signals when the outputs from the amplifiers 11a and 11b are analog signals, 13 is a CPU that controls the whole, and 14 is a gain controller that controls the gains of the amplifiers 11a and 11b. , 15 is a buzzer that sounds when light is detected by the disturbance light sensor 1a or when a contrast light is inputted. In accordance with the operation of the operation lever 3, this optical core discriminating device executes functions as a core line contrast (search) device and an optical direction discriminating device, and notifies the display unit 4 of the result by display output or buzzer 15.

  Regarding the optical direction discriminating function and the optical power measuring function realized in the optical core discriminating apparatus configured as described above, the disturbance light sensor 1a is automatically operated when the optical core discriminating head 20 is mounted. Will be described as an example. The method for attaching the head is as described above, and the description thereof is omitted here. First, when the optical fiber discriminating head 20 is attached to the main body 10, the optical fiber discriminating mode is set. In response to this, the CPU 13 operates the ambient light sensor 1a to detect light entering the apparatus from the outside. When the disturbance light sensor 1a detects light, the display unit 4 or the buzzer 15 notifies the operator of the fact based on the control of the CPU 13. On the other hand, when the disturbance light sensor 1a does not detect light, nothing may be notified, or notification may be performed by the display unit 4 or the buzzer 15. When the buzzer 15 is used for this notification, it is possible to distinguish by changing the alarm sound depending on whether light is detected or not.

  If the disturbance light is not detected by the disturbance light sensor 1a, the operator sets the optical fiber to be discriminated on the optical fiber core discrimination head 20, and then slides the operating lever 3 as shown in FIG. Keep as shown. Then, the leakage light from the optical fiber is received by PD1 and PD2, and the optical signal received by PD1 and PD2 is converted into an electrical signal, and the electrical signal is input to the amplifying units 11a and 11b.

  The amplifying units 11b and 11c amplify the input electrical signal based on the gain controlled by the gain control unit 14, and input the amplified signal to the CPU 13 via the A / D conversion units 12b and 12c. The CPU 13 compares the light levels of the leaked light detected by the PD1 and PD2 based on the input signal, determines the light direction from the comparison result, and displays and outputs the determination result on the display unit 4.

  Needless to say, the above-mentioned optical fiber identification device has a function as discrimination (ie, an ID tester) of optical fiber contrast light using one of PD1 and PD2.

  FIG. 4 is a block diagram showing another configuration example of the detection circuit of the optical fiber line discrimination device to which the present invention is applied, in which 16 is a phase difference detection unit. The other circuit configuration is the same as the circuit configuration shown in FIG. In this example, it is assumed that the phase difference detection unit 16 is added to the circuit configuration shown in FIG. 3 and the level difference of the leaked light is not seen in the light direction determination, but the phase difference of the leaked light is seen.

  First, when the optical core discriminating head 20 is attached to the main body 10, the optical core disc discriminating mode is set, and the CPU 13 operates the disturbance light sensor 1a in response to this, and the light entering the inside of the apparatus from the outside. Is detected. Similar to the example of FIG. 3, when the disturbance light sensor 1 a detects light, the display unit 4 or the buzzer 15 notifies that fact based on the control of the CPU 13. On the other hand, when the disturbance light sensor 1a does not detect light, nothing may be notified, or notification may be performed by the display unit 4 or the buzzer 15. When the buzzer 15 is used for this notification, it is possible to distinguish by changing the alarm sound depending on whether light is detected or not.

  If the disturbance light is not detected by the disturbance light sensor 1a, the operator sets the optical fiber to be discriminated on the optical fiber core discrimination head 20, and then slides the operating lever 3 as shown in FIG. Keep as shown. Then, the leakage light from the optical fiber is received by PD1 and PD2, and the optical signal received by PD1 and PD2 is converted into an electrical signal, and the electrical signal is input to the amplifying units 11a and 11b.

  The amplifying units 11a and 11b amplify the input electrical signal based on the gain controlled by the gain control unit 14, and the phase difference detection unit 16 uses the phase of the leakage light of each PD from the amplified signals from the amplifying units 11a and 11b. Is detected and input to the CPU 13. The CPU 13 compares the phases of leaked light detected by the PD1 and PD2 based on the phase of each input PD, determines the light direction from the comparison result, and displays and outputs the determination result on the display unit 4.

  As described above, according to the present invention, the disturbance light is detected by the built-in disturbance light sensor so that it can be notified to the worker, so that more accurate optical fiber identification can be performed without being affected by the disturbance light. Can do.

  Note that the present invention is not limited to the above-described embodiments, and it is obvious that the embodiments can be appropriately changed within the scope of the technical idea of the present invention. In addition, the number, position, shape, and the like of the constituent members are not limited to the above-described embodiment, and can be set to a suitable number, position, shape, and the like in practicing the present invention.

DESCRIPTION OF SYMBOLS 1 ... Upper housing | casing, 1a ... Disturbance light sensor, 2 ... Lower housing | casing, 3 ... Operation lever, 4 ... Display part, 5 ... Light receiving element holding part, 6 ... Light-shielding plate, 7 ... Protrusion part for head attachment, 8 ... Head mounting confirmation switch, 9 ... wavelength selection filter, 10 ... main body, 10a ... main body control, 10b ... sensor control, 11a, 11b ... amplification, 12a, 12b ... A / D conversion, 13 ... CPU, 14 DESCRIPTION OF SYMBOLS ... Gain control part, 15 ... Buzzer, 16 ... Phase difference detection part, 20 ... Optical fiber identification head, 21 ... Bending part, 22 ... Groove part, 23 ... Recessed part, 24 ... Optical fiber core wire.

Claims (4)

An optical core comprising: an optical core discriminating head formed with a bending portion for partially bending the optical fiber to leak an optical signal; and a main body portion to which the optical core disc discriminating head is detachably attached. A line discrimination device,
The main body includes a light receiving element holding means for holding a first light receiving element and a second light receiving element on both sides of a distal end portion formed with a concave portion to be fitted to the curved portion of the optical fiber identification head, An optical core comprising: a moving means for moving the light receiving element holding means relative to the main body; and an external light detecting means for detecting light entering the inside of the core wire discrimination device from the outside. Line discrimination device.   2. The optical fiber identification device according to claim 1, further comprising notification means for notifying a user when light is detected by the external light detection means.   3. The optical core discriminating apparatus according to claim 1, wherein the external light detection means is provided on an upper surface of a housing of the optical core discriminating apparatus.   4. The light according to claim 1, wherein the main body unit operates the external light detection unit when it is detected that the optical fiber identification head is attached. 5. Core wire discrimination device.

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