JP5564027B2 - Light measuring device - Google Patents

Description

  The present invention relates to a light measurement device that performs OTDR measurement and light intensity measurement.

  An OTDR (Optical Time Domain Reflectometer) is known as a measuring device used for laying and maintaining optical fibers (see, for example, Patent Document 1). The optical measurement device of Patent Document 1 includes a connection portion connectable to a measured optical fiber, a laser module that generates an optical pulse, and a light receiver that receives return light of the optical pulse incident on the measured optical fiber. Prepare OTDR measurement.

  At the site of optical fiber installation and maintenance, the signal light is actually incident on one end of the optical fiber to be measured, the signal light is received at the other end of the optical fiber to be measured, and the optical intensity is measured using a light intensity measuring device. Is also measured. In this way, the person in charge of installation and maintenance had to prepare a large number of measuring devices such as a signal light source device and a light intensity measuring device in addition to the OTDR measurement and carry them around the site.

  As a light measurement device in which a light source, an OTDR measurement device, and a light intensity measurement device are integrated, there is a light measurement device as disclosed in Patent Document 2, for example.

JP-A-6-167417 Japanese Patent Application No. 2010-146727

  One of the optical access network methods is PON (Passive Optical Network). In the optical access network adopting this PON, an OLT (Optical Line Terminal) and an ONU (Optical Network Unit) have a one-to-N configuration (N is a positive number). As a wavelength for data communication used for this PON, different wavelengths are defined such that the upstream (from ONU to OLT) is 1310 nm and the downstream (from OLT to ONU) is 1490 nm. More recently, in addition to the above wavelengths, 1550 nm is often used as a wavelength for transmitting video signals from the OLT. For this reason, at the time of construction or maintenance of the PON, it is necessary to discriminate light of each wavelength and measure its power.

  In general, optical fibers have different characteristics depending on the wavelength of communication light, and even if the loss of light of a certain wavelength is within an allowable range, the loss of light of another wavelength may not be within the allowable range. Therefore, in laying and maintaining a PON, it is usual to perform OTDR measurement at a plurality of wavelengths of communication light.

  However, the optical measurement device of Patent Document 2 cannot discriminate a plurality of light beams having different wavelengths and measure their light intensity, or perform OTDR measurement using a plurality of communication light wavelengths. A measuring device called a PON power meter can be used if it is used only for discriminating a plurality of light beams having different wavelengths and measuring the light intensity, but it is not possible to perform an OTDR measurement by itself and can be used as a light source. Because it was not possible, a separate OTDR measurement device and light source had to be prepared.

  Accordingly, in the present invention, a single light that can discriminate a plurality of lights having different wavelengths and perform light intensity measurement, or perform OTDR measurement at a plurality of wavelengths of communication light, and can also be used as a light source. The purpose is to provide a measuring device.

The optical measurement device according to the present invention includes one OLT (96) that emits communication light of the first wavelength and the second wavelength, and a plurality of ONUs (97_1 to 97_N) that emit communication light of the third wavelength. In the PON to be connected, an optical measurement device used for installation or maintenance of an optical fiber (93_3) connected to any one of the plurality of ONUs, the first connection to which the optical fiber can be connected Unit (1) and a measurement-dedicated light that is an optical pulse having a fourth wavelength different from any of the first wavelength, the second wavelength, or the third wavelength, and the first connection unit The first laser module (5) that emits toward the optical fiber and the return light of the measurement-dedicated light that is incident from the optical fiber via the first connection portion and receives the return light as an electrical signal A first light receiver (7) to convert; A light intensity measurement unit (21) for measuring the light intensity of the light received by the first light receiver based on the electrical signal, and the characteristics of the optical fiber based on the light intensity measured by the light intensity measurement unit In an optical measurement device (101, 102) comprising an OTDR measurement unit (22) for measuring the first communication wavelength measurement light and the third wavelength optical pulse, which are the first wavelength optical pulses. A second laser module (6) that selectively generates certain third communication wavelength measurement light, and communication light of the first wavelength and / or the second wavelength from the first connection section. And a first optical filter that receives light including the return light of the measurement-dedicated light and separates it into communication light of the first wavelength and / or the second wavelength and return light of the measurement-dedicated light (11), the first wavelength separated by the first optical filter, and Alternatively, the second optical filter (12) that receives the communication light of the second wavelength and separates the communication light of the first wavelength and the communication light of the second wavelength, and the second optical filter A second light receiver (8) that receives the communication light of the first wavelength separated in step (b) and converts it into an electrical signal; and the communication light of the second wavelength separated by the second optical filter. Receiving the third light receiver (9) for converting it into an electric signal and the measurement-dedicated light emitted from the first laser module, and passing the first optical filter through the first optical filter. A first optical coupler (14) for emitting the return light to the first light receiver, receiving the return light of the measurement-dedicated light separated by the first optical filter, and emitting the return light to the first light receiver. A second connecting part (2) connectable to the optical fiber, and the optical fiber in the second connecting part. And when the first communication wavelength measurement light or the third communication wavelength measurement light emitted from the second laser module is received and emitted to the second connection portion, A second light which receives the return light of the first communication wavelength measurement light or the third communication wavelength measurement light incident via the second connection portion and emits the return light to the first optical coupler; Optical coupler (15), the first communication wavelength measurement light or the third communication wavelength measurement light emitted from the second optical coupler, and the first optical filter separated by the second optical filter. And a third optical coupler (16) for receiving the light of the wavelength and emitting it to the second light receiver, wherein the first optical coupler further receives light from an external light source in the second connection section. When receiving the light that has passed through the second optical coupler, The reflected light that is emitted to the laser module and reflected by the end face of the first laser module is received and emitted to the second optical coupler, and the first communication wavelength measuring light or the third communication is emitted. When the return light of the wavelength measurement light is incident on the second connection portion, the return light that has passed through the second optical coupler is emitted to the first light receiver, and the second light receiver further The reflected light reflected by the end face of the first laser module is received through the first optical coupler, the second optical coupler, and the third optical coupler to be converted into an electrical signal, and the light intensity The measuring unit further measures the light intensity of the received light based on the electrical signal from the second light receiver or the third light receiver.

  Since the light of the fourth wavelength, the light of the first wavelength, and the light of the second wavelength are separated by the first optical filter and the second optical filter, the light intensity is discriminated by distinguishing a plurality of light of different wavelengths. Measurements can be made. Further, since the second laser module selectively generates light of the first or third wavelength, OTDR measurement can be performed at a plurality of wavelengths of communication light. Furthermore, since the first laser module and the second laser module are provided, the light measurement device according to the present invention can be used as a light source having a plurality of wavelengths.

  The measuring apparatus according to the present invention is also inserted between the first optical filter and the second optical filter, and is separated by the first optical filter and / or the second wavelength. A fourth optical coupler (17) for receiving the communication light having a wavelength of 2 and branching the light, and emitting one of the branched lights to the second optical filter, the first optical coupler, and the second optical coupler. Inserted between the optical coupler, and receives one of the light emitted from the first optical coupler and the other of the light emitted from the fourth optical coupler, and emits the second optical coupler, The light emitted from the second optical coupler is received and branched, and one of the branched lights is emitted to the first optical coupler, and the other of the branched lights is emitted to the fourth optical coupler. A fifth optical coupler (18) may be further provided.

  As a result, when the optical fiber is connected to the first connection unit, and any one of the plurality of ONUs is connected to the second connection unit, one of the OLT and the plurality of ONUs is You can keep communicating with each other.

  The measuring apparatus according to the present invention is also configured such that the optical fiber is connected to the first connection part, any one of the plurality of ONUs is connected to the second connection part, and the OLT and the In a state in which any one of a plurality of ONUs maintains communication, the OTDR measurement unit can perform the first laser module only during a time when the light intensity from the second light receiver is not measured by the light intensity measurement unit. May be used to measure the characteristics of the optical fiber.

  As a result, OTDR measurement can be performed while the OLT and the ONU remain in communication.

  According to the present invention, it is possible to perform light intensity measurement by discriminating light having a plurality of different wavelengths, or to perform OTDR measurement at a plurality of wavelengths of communication light and to be used as a light source. An optical measurement device can be provided.

The schematic diagram of PON is shown. An example of the optical measurement apparatus which concerns on Embodiment 1 is shown. An example of the optical measurement apparatus which concerns on Embodiment 2 is shown.

(Embodiment 1)
The first embodiment performs OTDR measurement at a plurality of wavelengths of communication light using the optical measurement device 101 according to the present invention.

  FIG. 1 shows a schematic diagram of a PON. An OLT 91 on the center side and a plurality of ONUs 97_1 to 97_N on the subscriber side are connected by an optical splitter 92. The plurality of ONUs 97_1 to 97_N are connected to the optical splitter 92 via optical fibers 93_1 to 93_N, respectively. The OLT 91 transmits communication light having a wavelength of 1490 nm for data signals and communication light having a wavelength of 1550 nm for video signals. Further, communication light having a wavelength of 1310 nm is transmitted from each of the plurality of ONUs 97_1 to 97_N.

  FIG. 2 shows an optical measurement apparatus 101 according to the first embodiment of the present invention. The light measurement apparatus 101 according to the first embodiment includes a first connection unit 1, a second connection unit 2, a first laser module 5, a second laser module 6, and a first light receiver 7. A second optical receiver 8, a third optical receiver 9, a first optical filter 11, a second optical filter 12, a first optical coupler 14, a second optical coupler 15, A third optical coupler 16, a light intensity measurement unit 21, and an OTDR measurement unit 22 are provided.

  Although not used in the first embodiment, the first laser module 5 emits measurement-dedicated light that is pulsed light having a wavelength of 1650 nm.

  The second laser module 6 selectively emits first communication wavelength measurement light that is an optical pulse with a wavelength of 1550 nm and third communication wavelength measurement light that is an optical pulse with a wavelength of 1310 nm. The second laser module 5 may be composed of, for example, a single tunable laser module, or may be composed of, for example, a laser module with a wavelength of 1550 nm, a laser module with a wavelength of 1310 nm, and an optical switch.

  The 1st light receiver 7 is a thing for measuring the optical intensity of the return light mentioned later, and converts the received light into an electric signal. The first light receiver 7 is composed of, for example, an APD (Avalanche Photo Diode).

  The second light receiver 8 and the third light receiver 9 are not used in the first embodiment, but are for measuring the light intensity of communication light, and convert the received light into an electrical signal. The second light receiver 8 and the third light receiver 9 are composed of, for example, PIN photodiodes.

  The first optical filter 11 is not used in the first embodiment, but separates return light having a wavelength of 1650 nm and communication light, which will be described later. The input port 111 is connected to the first connection unit 1. Further, light having a wavelength shorter than 1650 nm is output to the first port 112 on the output side, and is connected to the first optical filter 12. Furthermore, light having a wavelength of 1650 nm or more is output to the second port 113 on the output side, and is connected to the first optical coupler 14.

  Although the second optical filter 12 is not used in the first embodiment, the second optical filter 12 is for separating communication light having a wavelength of 1490 nm and communication light having a wavelength of 1550 nm. The input side port 121 is connected to the first optical filter 11. Further, light having a wavelength longer than 1490 nm is output to the first port 122 on the output side, and is connected to the second light receiver 8. Further, light having a wavelength of 1490 nm or less is output to the second port 123 on the output side, and is connected to the third light receiver 9.

  The first optical coupler 14 has two ports (141, 142, 143, 144) at both ends, the first port 141 at one end is connected to the first laser module 5, and the second port 142 is connected to the first port 142. Connected to the photoreceiver 7. The first port 143 at the other end is connected to the second optical coupler 15, and the second port 144 is connected to the first optical filter 11.

  The second optical coupler 15 has two ports (151, 152, 153, 154) at both ends, the first port 151 at one end is connected to the second laser module 6, and the second port 152 is connected to the first port 152. The optical coupler 14 is connected. The first port 153 at the other end is connected to the second connection unit 2, and the second port 154 is connected to the third optical coupler 16.

  The third optical coupler 16 has two ports (161, 162) at one end and one port 163 at the other end. The first port 161 at one end is connected to the second optical coupler 15, and the second port 162 is connected to the second port 162. The second optical filter 12 is connected. The other port 163 is connected to the second light receiver 8.

  The light intensity measurement unit 21 receives the light of the light received by each of the light receivers 7 to 9 based on the electrical signals converted by the first light receiver 7, the second light receiver 8, and the third light receiver 9, respectively. Measure strength.

  The OTDR measurement unit 22 performs OTDR measurement based on the measurement result measured by the light intensity measurement unit 21.

  Now, OTDR measurement is performed on the optical fiber 93_3 for connecting the ONU 97_3 and the optical splitter 92 in FIG. For this purpose, one end of the optical fiber 93_3 on the ONU 97_3 side is cut and connected to the second connection unit 2 of the optical measurement device 101 according to the first embodiment.

  In this case, the first laser module 5 of the optical measurement device 101 according to the first embodiment is not activated, and the first communication wavelength measurement light, which is an optical pulse with a wavelength of 1550 nm, or a wavelength of 1310 nm from the second laser module 6. The third communication wavelength measuring light that is the light pulse of is selectively emitted.

  The first or third communication wavelength measurement light is emitted from the second connection unit 2 to the optical fiber 93_3 via the second optical coupler 15. The communication wavelength measurement light incident on the optical fiber 93_3 causes reflection due to Rayleigh scattering or a reflection point while propagating through the optical fiber 93_3, and return light from the optical fiber 93_3 toward the second connection unit 2 is generated.

  This return light enters the first light receiver 7 from the second connection portion 2 via the second optical coupler 15 and the first optical coupler 14.

  The light intensity of the return light incident on the first light receiver 7 is measured by the light intensity measurement unit 21, and the OTDR measurement unit 22 performs OTDR measurement based on the measurement result. The OTDR measurement using the communication wavelength measurement light or the third communication wavelength measurement light is realized by the single optical measurement apparatus 101 according to the first embodiment.

  In the first embodiment, the optical fiber 93_3 is connected to the OLT 96 via the optical splitter 92, and the communication light from the OLT 96 and the optical measurement apparatus 101 according to the first embodiment are used while the OLT 96 is in operation. OTDR measurement of the optical fiber 93_3 cannot be performed because the first communication wavelength measurement light affects each other.

(Embodiment 2)
In the second embodiment, the OTDR measurement for the optical fiber 93_3 is performed with the measurement-dedicated light having a wavelength of 1650 nm. The structure of the light measurement device according to the second embodiment is the same as that of the light measurement device 101 according to the first embodiment shown in FIG. However, one end of the optical fiber 93_3 is connected to the first connection unit 1 of the light measurement device 101.

  In the light measurement apparatus 101 according to the second embodiment, the second laser module 6 is not activated, and the measurement dedicated light having a wavelength of 1650 nm is emitted from the first laser module 5.

  The measurement-dedicated light is emitted from the first connection unit 1 to the optical fiber 93_3 via the first optical coupler 14 and the first optical filter 11. The return light generated in the optical fiber 93_3 enters the first light receiver 7 from the first connection portion 1 via the first optical filter 11 and the first optical coupler 14.

  The light intensity of the return light incident on the first light receiver 7 is measured by the light intensity measurement unit 21, and the OTDR measurement unit 22 performs OTDR measurement based on the measurement result, whereby the measurement-dedicated light for the optical fiber 93_3 is obtained. OTDR measurement by is realized.

  In the second embodiment, the first optical filter 11 is shorter than the wavelength of 1650 nm even if the first to third communication lights are incident on the first connection unit 1 in addition to the return light of the measurement-dedicated light. The light is separated and output to the first port 112 on the output side, and almost only the return light of the measurement-dedicated light is output to the second port 113 on the output side. For this reason, even if the OLT 91 is in operation, OTDR measurement can be performed without being affected by the communication light.

(Embodiment 3)
The light measurement apparatus 101 according to the present invention can also be used as a light source having a wavelength of 1310 nm, 1550 nm, or 1650 nm. The structure of the light measurement device according to the third embodiment is the same as that of the light measurement device 101 according to the first embodiment shown in FIG. The optical device that requires light from the light source is connected to the second connection unit 2 of the light measurement device 101 according to the third embodiment.

  When the light measurement apparatus 101 according to the third embodiment is used as a stabilized light source having a wavelength of 1310 nm or 1550 nm, the second laser module 6 is activated. Light having a wavelength of 1310 nm or 1550 nm selectively emitted from the second laser module 6 is incident on the first port 151 at one end of the second optical coupler 15, and is then transmitted from the first port 153 at the other end to the second port. And is incident on the second light receiver 8 from the second port 154 at the other end.

  The light intensity of the light incident on the second light receiver 8 is measured by the light intensity measuring unit 21. By controlling the current input to the second laser module 6 so that the light intensity measured by the light intensity measurement unit 21 is kept constant by a light intensity stability control unit (not shown), the second connection unit 2. The light intensity of the light emitted from can be kept constant.

  In addition, when the light measurement apparatus 101 according to the third embodiment is used as a light source having a wavelength of 1650 nm, the first laser module 5 is activated. The light having a wavelength of 1650 nm emitted from the first laser module 5 is emitted to the second connection unit 2 via the first optical coupler 14 and the second optical coupler 15, and the second optical coupler. 15 enters the second light receiver 8. By the light intensity stability control unit, the current input to the first laser module 5 is controlled so as to keep the light intensity measured by the light intensity measurement unit 21 constant, so that the light is emitted from the second connection unit 2. The light intensity of the emitted light can be kept constant.

(Embodiment 4)
The light measuring device 101 according to the present invention can also be used as a light intensity measuring device for high output light from an external light source. The structure of the light measurement device according to the fourth embodiment is the same as that of the light measurement device 101 according to the first embodiment shown in FIG. High-power light is incident on the second connection unit 2 of the light measurement apparatus 101 according to the fourth embodiment.

  High-power light incident on the second connection unit 2 is incident on the first laser module 5 via the second optical coupler 15 and the first optical coupler 14. At this time, an optical shutter is provided between the first optical coupler 14 and the first light receiver 7 so that high output light does not enter the first light receiver 7, and the light intensity according to the fourth embodiment. When used as a measuring device, this optical shutter may be closed.

  The high-power light that has entered the first laser module 5 is reflected by the end face of the first laser module 5, returns to the first optical coupler 14 again, passes through the second optical coupler 15, and passes through the second optical coupler 15. The light enters the light receiver 8. The light intensity measurement unit 21 measures the light intensity of the light incident on the second light receiver 8. Then, the light intensity measurement unit 21 corrects the measured light intensity with a correction value stored in advance. As the correction value, for example, a difference between the light intensity of light incident on the second connection unit 2 and the light intensity measured by the second light receiver 8 is measured in advance for each wavelength, and the light intensity measurement unit 21 is measured. Store it in. As a result, the light measurement apparatus 101 according to the fourth embodiment can measure the light intensity of high-power light using an external light source.

(Embodiment 5)
The light measurement apparatus 101 according to the present invention can also perform light intensity measurement by discriminating communication light having a wavelength of 1490 nm and a wavelength of 1550 nm from the OLT 96. The structure of the light measurement device according to the fifth embodiment is the same as that of the light measurement device 101 according to the first embodiment shown in FIG. Communication light from the OLT 96 is incident on the first connection unit 1 of the light measurement apparatus 101 according to the fifth embodiment.

  The communication light incident on the first connection unit 1 is output to the first port 112 on the output side of the first optical filter 11 and is incident on the second optical filter 12. Of the communication light incident on the second optical filter, the communication light having a wavelength of 1550 nm is output to the first port 122 on the output side of the second optical filter 12 and passes through the third optical coupler 16 to the first optical fiber. 2 is incident on the light receiver 8. The light intensity measurement unit 21 measures the light intensity of the light incident on the second light receiver 8.

  Of the communication light incident on the second optical filter, communication light having a wavelength of 1490 nm is output to the second port 123 on the output side of the second optical filter 12 and incident on the third light receiver 9. The The light intensity measurement unit 21 measures the light intensity of the light incident on the third light receiver 9. As a result, the light measurement apparatus 101 according to the fifth embodiment can discriminate communication light having a wavelength of 1490 nm and a wavelength of 1550 nm from the OLT 96 and perform light intensity measurement.

(Embodiment 6)
The optical measurement apparatus according to the sixth embodiment is for realizing OTDR measurement using measurement-dedicated light having a wavelength of 1650 nm while maintaining the communication state between the OLT 96 and the ONU 97_3.

  FIG. 3 shows an optical measurement device 102 according to the sixth embodiment of the present invention. In the optical measurement device 102 according to the sixth embodiment, a fourth optical coupler 17 and a fifth optical coupler 18 are added to the configuration of the optical measurement device 101 according to the first to fifth embodiments of the present invention. Yes.

  The fourth optical coupler 17 has one port 171 at one end and two ports (172, 173) at the other end, and the port 171 at one end is connected to the first port 112 on the output side of the first optical filter 11. Has been. The first port 172 at the other end is connected to the input side port 121 of the second optical filter 12, and the second port 173 is connected to the fifth optical coupler 18.

  The sixth optical coupler 18 has two ports (181, 182) at one end and one port 183 at the other end. The first port 181 at one end is connected to the fourth optical coupler 17, and the second port 182 is connected to the second port 182. It is connected to the first optical coupler 14. The other end port 183 is connected to the second optical coupler 15.

  The optical fiber 97 </ b> _ <b> 3 for OTDR measurement is connected to the first connection unit 1. Further, the ONU 97 — 3 is connected to the second connection unit 2. Communication light having a wavelength of 1490 nm and a wavelength of 1550 nm from the OLT 96 enters from the first connection unit 1, and passes through the first optical filter 11, the fourth optical coupler 17, the fifth optical coupler 18, and the second optical coupler 15. Then, the light is emitted from the second connection unit 2 to the ONU 97_3. In addition, communication light having a wavelength of 1310 nm from the ONU 97_3 is incident from the second connection unit 2 and then emitted from the first connection unit 1 to the OLT 96 via a path reverse to the above. Thereby, even if the optical measurement apparatus 102 according to the sixth embodiment is performing OTDR measurement, the OLT 96 and the ONU 97_3 can maintain the communication state.

  Since the communication light incident on the first connection unit 1 from the OLT 96 is not output to the second port 113 on the output side by the first optical filter 11, the first light receiver 7 during the OTDR measurement is affected. Don't give. However, the communication light incident on the second connection unit 2 from the ONU 97_3 is also incident on the first light receiver 7, and the OTDR measurement is affected as it is. A method for removing the influence of communication light from the ONU 97_3 will be described below.

  In the PON, communication lights from the plurality of ONUs 97_1 to ONU97_N are time-division multiplexed. Therefore, the communication light from the ONU 97_3 is output in a burst shape. Here, according to the method described in the fourth embodiment, the communication light reflected by the end face of the first laser module 5 is received by the second light receiver 8 and measured by the light intensity measuring unit 21, thereby bursting. It is possible to know whether or not the communication light is incident. Then, if the OTDR measurement using the measurement-dedicated light with a wavelength of 1650 nm is performed by the method described in the embodiment 2 only when the burst communication light is not incident, the OLT 96 and the ONU 97_3 remain in the communication state. OTDR measurement can be realized accurately.

  As described above, it is possible to perform light intensity measurement by discriminating light having a plurality of different wavelengths, or to perform OTDR measurement at a plurality of wavelengths of communication light, with one optical measurement device according to the present invention. And since it can be used also as a light source, the number of apparatuses carried for installation and maintenance of an optical fiber can be reduced. In addition, since many components are shared by a plurality of functions in the optical measurement device according to the present invention, it can be made smaller than the integration of single-function devices, and the device cost can be reduced. Furthermore, the optical measurement device 102 according to the sixth embodiment can perform OTDR measurement of an optical fiber while maintaining the communication state between the OLT and the ONU, and can be used for an optical fiber monitoring application or the like.

  The present invention can be applied to the information communication industry.

1: 1st connection part 2: 2nd connection part 5: 1st laser module 6: 2nd laser module 7: 1st light receiver 8: 2nd light receiver 9: 3rd light receiver 11 : First optical filter 12: second optical filter 14: first optical coupler 15: second optical coupler 16: third optical coupler 17: fourth optical coupler 18: fifth optical coupler 21: Light intensity measurement unit 22: OTDR measurement unit 92: Optical splitter 96: OLT
97_1 to 97_N: ONU

Claims (3)

One OLT (Optical Line Terminal) (96) that emits communication light of the first wavelength and the second wavelength, and a plurality of ONUs (Optical Network Units) (97_1 to 97_N) that emit communication light of the third wavelength; In a PON (Passive Optical Network) for connecting the optical fiber (93_3) connected to any one of the plurality of ONUs, an optical measurement device used for installation or maintenance,
A first connection (1) to which the optical fiber can be connected;
A measurement-dedicated light that is an optical pulse having a fourth wavelength different from any of the first wavelength, the second wavelength, and the third wavelength is generated and emitted toward the optical fiber through the first connection portion. A first laser module (5) to
A first light receiver (7) that receives the return light of the measurement-dedicated light incident from the optical fiber via the first connection portion and converts the return light into an electrical signal;
A light intensity measuring unit (21) for measuring the light intensity of light received by the first light receiver based on the electrical signal;
In an optical measurement device (101, 102) comprising: an OTDR (Optical Time Domain Reflectometer) measurement unit (22) for measuring characteristics of the optical fiber based on the light intensity measured by the light intensity measurement unit;
A second laser module (6) that selectively generates a first communication wavelength measurement light that is an optical pulse of the first wavelength and a third communication wavelength measurement light that is an optical pulse of the third wavelength. When,
Upon receiving light including the communication light of the first wavelength and / or the second wavelength and the return light of the measurement-dedicated light from the first connection unit, the first wavelength and / or A first optical filter (11) for separating the communication light of the second wavelength and the return light of the measurement-dedicated light;
The communication light having the first wavelength and / or the second wavelength separated by the first optical filter is received and separated into the communication light having the first wavelength and the communication light having the second wavelength. A second optical filter (12) that
A second light receiver (8) that receives the communication light of the first wavelength separated by the second optical filter and converts it into an electrical signal;
A third light receiver (9) for receiving communication light of the second wavelength separated by the second optical filter and converting it into an electrical signal;
The measurement-dedicated light emitted from the first laser module is received, emitted to the first connection portion via the first optical filter, and separated by the first optical filter. A first optical coupler (14) for receiving the return light of the measurement-dedicated light and emitting the return light to the first light receiver;
A second connecting part (2) connectable with the optical fiber;
When the optical fiber is connected to the second connection portion, the first communication wavelength measurement light or the third communication wavelength measurement light emitted from the second laser module is received and the first communication wavelength measurement light is received. 2 and receiving the return light of the first communication wavelength measurement light or the third communication wavelength measurement light that is incident through the second connection part and receiving the return light from the first connection wavelength measurement light. A second optical coupler (15) that emits to one optical coupler;
Receiving the first communication wavelength measurement light or the third communication wavelength measurement light emitted from the second optical coupler, and the light of the first wavelength separated by the second optical filter; A third optical coupler (16) emitting to the second light receiver,
The first optical coupler further receives the light that has passed through the second optical coupler and emits the light to the first laser module when light from an external light source is incident on the second connection portion. The reflected light reflected by the end face of the first laser module is emitted to the second optical coupler, and the first communication wavelength measurement light or the third communication wavelength measurement light is transmitted. When return light is incident on the second connection portion, the return light that has passed through the second optical coupler is emitted to the first light receiver,
The second light receiver further receives the reflected light reflected by the end face of the first laser module via the first optical coupler, the second optical coupler, and the third optical coupler, and is electrically Convert it into a signal
The light intensity measuring unit further measures the light intensity of light received based on the electrical signal from the second light receiver or the third light receiver. Receiving communication light of the first wavelength and / or the second wavelength inserted between the first optical filter and the second optical filter and separated by the first optical filter; And a fourth optical coupler (17) for emitting one of the branched lights to the second optical filter;
Inserted between the first optical coupler and the second optical coupler, and receives one of the light emitted from the first optical coupler and the other of the light emitted from the fourth optical coupler. The light is emitted to the second optical coupler, and the light emitted from the second optical coupler is received and branched, and one of the branched lights is branched to the first optical coupler. The optical measurement device according to claim 1, further comprising a fifth optical coupler (18) for emitting the other to the fourth optical coupler.
The optical fiber is connected to the first connection unit, and any one of the plurality of ONUs is connected to the second connection unit, and any one of the OLT and the plurality of ONUs communicates. In a state of keeping
The OTDR measurement unit measures the characteristics of the optical fiber by the first laser module only during a time when the light intensity from the second light receiver is not measured by the light intensity measurement unit. The light measurement apparatus according to claim 2.