JP2010276862A - Optical fiber cord and method of identifying coated optical fiber - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical fiber cord in which coated optical fiber is identified with visible light, when the optical fiber is used in which an optical transmission part or a core is enclosed by a plurality of cavities. <P>SOLUTION: The optical fiber cord uses the optical fiber in which the optical transmission part or the core 21 is enclosed by a plurality of cavities 23; a light of which the wavelength is in the range of 380 to 1,200 nm is transmitted through the gap between the cavities 23; the optical fiber is covered by a UV coat 24; Kevlar (R) fibers 25 and a cord outer coat 26; and when the light passes through the UV coat 24, the Kevlar fibers 25 and the cord outer coat 26 in the direction of cross section, the total transmittance is 0.1% or larger and 70% or smaller for the wavelength range of 380 to 1,200 nm. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  In the present invention, for example, when an optical fiber in which a light propagation part or a core is surrounded by a plurality of holes is used in a cross section of HAF (Hall Assist Fiber), PCF (Photonic Crystal Fiber) or the like, a core wire by visible light is used. The present invention relates to an optical fiber cord that enables control and a method for controlling the cores thereof.

  With the rapid spread of optical access services against the backdrop of the realization of 20 million optical access in 2010, the era of mass service of optical services has been entered, and accordingly, in-house optical facilities have increased rapidly (for example, Non-Patent Document 1, 2).

  In the next-generation in-house optical equipment, it is expected that the increasing optical equipment will be accommodated in a limited space. Therefore, there is a possibility that space saving by higher density than before is required. However, as the density increases, there is a concern that optical cords, optical cables, etc. will become congested, making maintenance and management difficult. For this reason, in the next-generation in-house optical equipment, there is a demand for in-house optical wiring and management technology having both safety and certainty corresponding to higher density.

  FIG. 2 is an explanatory diagram illustrating a conventional in-house optical wiring facility. As shown in FIG. 2, the in-house optical wiring facility of the communication station building 11 is an identification that connects a transmission device OLT (Optical Line Terminal) that provides an IP service or the like and a dedicated wiring rack IDM-B (IDM: Integrated Distribution Module). An in-house optical cable (optical code) 13 having a tag 12 and an in-house optical cable (optical code) 13 having an identification tag 12 for connecting the dedicated wiring rack IDM-B and the dedicated wiring rack IDM-A. The dedicated wiring rack IDM-A is connected to a customer home 15 by an off-site optical cable (optical cord) 14. In this case, efficient optical wiring accommodation is realized by installing dedicated wiring racks IDM-A and IDM-B on the outside side and the OLT side, respectively, and dividing the functions (see, for example, Non-Patent Documents 3 to 6). ).

  Furthermore, a core-contrast technique has been developed that identifies a desired optical fiber core that is very important for maintenance and operation. By comparing the control light having a wavelength longer than the signal wavelength band into the optical fiber, bending the fiber, and monitoring the control light leaking, it is possible to perform contrast control (for example, see Non-Patent Document 7).

  As described above, the current in-house optical wiring has a configuration that is considered for the purpose of high efficiency operation and easy workability. Furthermore, since it is expected that higher density will be required for next-generation in-house optical wiring equipment, a problem that may occur during optical wiring is that an optical cord or optical cable may be accidentally hooked during work such as new installation or abolition. This may increase the bending loss and cut off communication. Therefore, it has been proposed to replace the optical fiber cord of the optical fiber cord and the optical cable with a hole assist fiber (HAF) excellent in bending loss characteristics from the current single mode fiber (for example, see Non-Patent Document 8). However, because HAF has a structure in which bending loss is unlikely to occur, the control light does not leak and the cord control is difficult.

H. Shinohara, “Overview of Japanese FTTH market and NTT ’s strategies for entering full-scale FTTH era,” presented at the 32nd European Conference on Optical Communication, Cannes, France September 24-28, 2006. O. Yamauchi, “Trends in optical access network technologies toward ‘30 million optical subscribers by 2010’, ”NTT Technical Review 4, 21-28 (2006). M. Tachikura, K. Mine, H. Izumita, S. Uruno, M. Nakamura, “Newly developed optical fiber distribution system and cable management in central office,” Proc. 50th IWCS, pp. 98-105. Shigenori Uruno, Fumi Izumida, Satoshi Nakamura, “Economic MU Connector Technology in In-House Optical Wiring Management System,” NTT Technical Journal, vol. 15, no. 10, pp. 12-15, 2003 Shigenori Uruno, Masao Tatekura, Fumi Izumida, Tsuneji Mine, Nobuo Tomita “Integrated Wiring Module in the In-House Optical Wiring Management System (IDM Design)”, Shingaku Sodai, B-10-25, 2000 Koji Mine, Yoshitaka Enomoto, Hisashi Izumita, M. Tachikura, N. Tomita, J. Yamaguchi, K. Sasakura and K. Kaneko, “Automatic Cross-connecting Fiber Termination Module,” APCC / OECC'99, vol. 1, pp 267-269, 1999 Masahito Ari, Yuji Higashi, Yasutaka Enomoto, Katsaki Suzuki, Noriyuki Araki, Shigenori Uruno, Tsuneichi Watanabe, “Optical Media Network Operation Technology Supporting Expanding Optical Access Networks,” NTT Technical Journal, vol. 18, no. 12 , pp. 58-61, 2006. Shinichi Aoki, Shigenori Uruno, Masaki Wada, Toshitaka Enomoto, Yuji Higashi, “Next-generation in-house optical wiring and management technology”, IEICE Technical Report, OFT2008-50, pp. 19- 22, 2008.

  The present invention has been made in view of the above circumstances. For example, an optical fiber in which a light propagation portion or a core is surrounded by a plurality of holes in a cross section of HAF (Hall Assist Fiber), PCF (Photonic Crystal Fiber) or the like. An object of the present invention is to realize a cord contrast capable of specifying a desired optical fiber cord even with the used optical fiber cord. Furthermore, by using visible light as the reference light, it is possible to realize simple core line contrast by visual recognition.

  In order to achieve the above object, the present invention is an optical fiber cord using an optical fiber in which a light propagation part or core is surrounded by a plurality of holes and light in a wavelength range of 380 to 1200 nm can propagate through the gaps of the holes. A covering member is provided so as to cover the optical fiber, and a covering member through which light in a wavelength range of 380 to 1200 nm passes is used as the covering member.

  In the optical fiber cord, the present invention uses a covering member having a transmittance of 0.1% or more and 70% or less in a wavelength range of 380 to 1200 nm when light passes through the covering member in the cross-sectional direction. As the covering member, a covering member composed of at least one of a UV coating, a strength retaining material, and a cord outer coating is used.

  Further, the present invention is characterized in that the optical fiber cord contains particles that scatter light in a wavelength range of 380 to 1200 nm in at least one of a UV coating, a strength holding material, and an outer coating of the cord.

  According to the present invention, in the optical fiber cord, when the optical fiber cord is bent, at least one of the wavelengths in the wavelength range of 380 to 1200 nm out of the light propagating through the optical fiber is leaked to 1200 nm. It is characterized by not leaking light having a wavelength exceeding.

  According to the present invention, in the optical fiber cord, when the optical fiber cord is bent with a radius of 5 mm, light having a wavelength in the wavelength range of 380 to 1200 nm out of light propagating through the optical fiber leaks. However, it does not leak light having a wavelength exceeding 1200 nm.

  The present invention is also characterized in that the optical fiber cord includes an optical coupler that couples light having a wavelength range of 380 to 1200 nm to an optical propagation portion or a core of the optical fiber cord.

  The present invention further includes an optical coupler for combining the light in the wavelength range of 380 to 1200 nm without affecting the signal light propagating through the optical propagation part or the core of the optical fiber cord. It is a feature.

  Further, the present invention is characterized in that in the optical fiber cord, a light source that emits light having a wavelength of at least one of a wavelength range of 380 to 1200 nm and 1300 to 1700 nm or modulated light is connected.

  According to the present invention, in the optical fiber cord, a fiber optic cord is sandwiched, and the optical fiber cord is bent to provide a cord contrast device capable of detecting the power or modulation signal of light in the wavelength range of 380 to 1200 nm. It is characterized by this.

  The present invention also relates to a method of contrasting an optical fiber cord using an optical fiber in which a light propagation part or core is surrounded by a plurality of holes and light in a wavelength range of 380 to 1200 nm can propagate through the gaps of the holes. The optical fiber cord is bent so that at least one of the wavelengths in the wavelength range of 380 to 1200 nm out of the light propagating through the optical fiber is leaked, and light having a wavelength exceeding 1200 nm is not leaked. It is characterized by performing a contrast control.

  The optical fiber cord of the present invention has a structure in which holes are provided outside the light propagation region (signal propagation region) in order to obtain excellent bending loss characteristics, and the space between the holes is visible (380 to 750 nm) or short. It is characterized in that light in the near infrared region (750 to 1200 nm) on the wavelength side can propagate, and further passes through the UV coating covering the optical fiber, the strength holding material, and the outer coating of the cord.

  When using near-infrared light (1300 to 1700 nm) for communication signal light and short-wavelength near-infrared light for control light, a holey optical fiber in a communication state that was difficult with conventional control light Allows for contrast control. Therefore, even if it bends, a core line contrast is possible without affecting communication.

  Further, when visible light is used as the control light, the core wire can be visually confirmed only by bending the optical fiber cord by hand without using a core wire contrast device or the like. It is also possible to visually check for abnormal bending that has occurred in the optical fiber cord, which leads to improved maintainability of the wiring.

  By optimizing the fiber parameters and the wavelength of the reference light, it is also possible to make the entire optical fiber cord shine for comparison. Further, by adding modulation to the reference light, it becomes easy to distinguish from other optical fiber cords. INDUSTRIAL APPLICABILITY The present invention greatly improves the certainty and ease of work in maintenance work of optical equipment and greatly contributes to economic efficiency.

It is sectional drawing which shows the optical fiber cord which concerns on the 1st Embodiment of this invention. It is structure explanatory drawing which shows the conventional in-house optical wiring installation. It is a characteristic view which shows an example of the wavelength dependence of the light leakage amount of the core propagation light at the time of curve provision of HAF and SMF which concerns on the 1st Embodiment of this invention. FIG. 6 is a characteristic diagram showing an example of dependency of a gap between holes on a leakage amount of visible light having a wavelength of 650 nm and a bending loss of light having a wavelength of 1550 nm in the HAF according to the first embodiment of the present invention. It is a characteristic view which shows an example of the wavelength dependence of the transmission loss of UV coating of a 1.1 mm outer diameter optical fiber cord concerning the 1st Embodiment of this invention, a Kevlar, and a cord outer coating. It is a characteristic view which shows an example of the bending diameter dependence of the leakage power of visible light with a wavelength of 650 nm, and bending loss about the 1.1 mm outer diameter optical fiber cord which concerns on the 1st Embodiment of this invention. It is a characteristic view which shows an example of the cord length dependence of light leakage power about the optical fiber cord of 1.1 mm outer diameter which concerns on the 1st Embodiment of this invention. It is sectional drawing which shows the optical fiber cord which concerns on the 2nd Embodiment of this invention, and a structure explanatory drawing which shows the core wire contrast method of an optical fiber cord. It is a characteristic view which shows an example of the code length dependence of the light leakage power which concerns on the 2nd Embodiment of this invention. It is sectional drawing which shows the optical fiber cord which concerns on the 3rd Embodiment of this invention, and a structure explanatory drawing which shows the core wire contrast method of an optical fiber cord. It is a characteristic view which shows an example of the code length dependence of the light leakage power which concerns on the 3rd Embodiment of this invention. It is composition explanatory drawing which shows the optical fiber cord core line contrast method which concerns on the 4th Embodiment of this invention.

Hereinafter, embodiments of the present invention will be described in detail.
[First embodiment]
1A and 1B show an optical fiber cord according to a first embodiment of the present invention, in which FIG. 1A is a longitudinal sectional view and FIG. 1B is a transverse sectional view. In FIGS. 1A and 1B, a core 21 is provided at the central shaft portion, and a hole layer 22 is provided coaxially around the core 21, which is an optical propagation portion (signal propagation portion). The layer 22 is provided with six holes 23 arranged in an annular shape around the core 21 to constitute a HAF (Hall Assist Fiber).

  A UV coating 24 made of a curable resin by ultraviolet light irradiation is provided around the hole layer 22, and a Kevlar 25 and a cord outer coating 26 are provided around the UV coating 24. The Kevlar 25 functions as a cord strength retaining material, and an aramid fiber or the like is used as the material. The cord outer coating 26 has non-halogen polymer, flame retardant polyolefin, and the like that are excellent in flame retardancy, are not easily bent and have good sliding properties.

  The gap of the air holes 23 is capable of propagating light in the visible region (380 to 750 nm) or near-infrared region (750 to 1200 nm) on the short wavelength side, and further includes a coating made of a UV coating 24, a Kevlar 25, and an outer cord coating 26. The total transmittance of the member when light passes in the cross-sectional direction is 0.1% or more and 70% or less in the wavelength range of 380 to 1200 nm.

In FIG. 1, 27 is communication light, and 28 is visible light (650 nm).
That is, near-infrared light (1300 to 1700 nm) in the middle wavelength region as communication light and visible light (380 to 750 nm) or near-infrared light (750 to 1200 nm) in the short wavelength region as control light, the core 21 of the optical fiber cord. When the optical fiber cord is curved with a radius of 5 mm, for example, the visible light (380 to 750 nm) of the control light or the near infrared light (750 to 1200 nm) in the short wavelength region is inserted into the gap of the hole 23. Since the wavelength is much shorter than that, the gap between the holes 23 is sewn and leaks to the outer edge of the HAF, passes through the UV coating 24, passes through the Kevlar 25, passes through the cord outer coating 26, and passes outside the optical fiber cord. To be emitted.

  On the other hand, the mid-wavelength near-infrared light (1300 to 1700 nm), which is communication light having a wavelength exceeding 1200 nm, is not sufficiently short in wavelength compared to the gaps of the holes 23, so Even if the optical fiber cord is bent with a radius of, for example, 5 mm, it is not radiated to the outside (light leakage).

  Therefore, even if the optical fiber cord is bent with a radius of, for example, 5 mm, the cords can be compared without affecting the communication. Further, when visible light is used as the control light, the core wire can be visually confirmed only by bending the optical fiber cord by hand without using a core wire contrast device or the like. It is also possible to visually check for abnormal bending that has occurred in the optical fiber cord, which leads to improved maintainability of the wiring.

  It is also possible to make the entire optical fiber cord shine by optimizing the HAF fiber parameters and the wavelength of the reference light. Further, by adding modulation to the reference light, it becomes easy to distinguish from other optical fiber cords.

  In the optical fiber cord, at least one of the UV coating 24, the Kevlar 25, and the outer cord coating 26 may contain particles that scatter light in the wavelength range of 380 to 1200 nm.

  Further, in the optical fiber cord, an optical coupler that couples light having a wavelength range of 380 to 1200 nm to the optical propagation portion or core of the optical fiber cord may be provided, and the optical propagation portion or core of the optical fiber cord may be provided. You may provide the optical coupler which combines the light of wavelength range 380-1200 nm, without affecting the signal light to propagate.

  Further, a light source that emits light or modulated light having at least one wavelength in the wavelength range of 380 to 1200 nm and 1300 to 1700 nm may be connected to the optical fiber cord.

  Further, an optical fiber cord may be sandwiched between the optical fiber cords to bend the optical fiber cord so as to detect a power or modulation signal of light having a wavelength range of 380 to 1200 nm.

  Fig. 3 (a) shows the wavelength dependence of the amount of leakage light of the HAF core propagating light when it is curved once with a radius of 5 mm, and Fig. 3 (b) shows the SMF core when curved once with a radius of 5 mm. This represents the wavelength dependence of the amount of leakage of propagating light. Here, it is a value obtained by measuring with an optical fiber and subtracting the absorption loss of the UV coating. For comparison, the leakage spectrum of a conventional single mode fiber (SMF) was also measured. As can be seen from the figure, in the HAF, the amount of light leakage increases rapidly as it goes from the wavelength of 1200 nm to the short wavelength side. On the other hand, the loss of SMF increases as it goes to the longer wavelength side, and shows a symmetric change with HAF. In SMF, the control light is set to the long wavelength side of the communication wavelength, and the optical fiber cord is bent, so that the optical fiber cord can be controlled. In the HAF of one embodiment of the present invention, the control light is set to the short wavelength of the communication wavelength. By setting the optical fiber cord to bend and leaking light by bending the optical fiber cord, it is possible to control the cords in the communication state.

  FIG. 4 shows the dependence of the leakage amount of visible light having a wavelength of 650 nm and the bending loss of a wavelength of 1550 nm on the gap of the hole when the HAF used in FIG. 3 is bent with a radius of 5 mm (R5). As can be seen from FIG. 4, when the gap between the holes is increased, the amount of visible light leakage having a wavelength of 650 nm starts to increase and saturates at a certain point. As the void gap increases further, the bending loss at the wavelength of 1550 nm begins to increase. Therefore, it is desirable to set the size of the void gap between the gap values at which the two quantities begin to increase. Further, when the amount of visible light transmitted is large, the light attenuation in the longitudinal direction of the fiber is abrupt. Therefore, when it is desired to propagate a long distance, it can be dealt with by reducing the gap between the holes. However, in that case, the leakage light quantity becomes small, and the visibility may deteriorate.

  FIG. 5 shows the wavelength dependence of the transmission loss of the UV coating, Kevlar, and cord outer coating of the 1.1 mm outer diameter optical fiber cord. All the transmittances are calculated as transmission distances transmitted in the fiber cross-sectional direction. In this embodiment, the UV coating was 190 μm, the Kevlar was 20 μm, and the outer coating was 170 μm. Further, since the Kevlar is in the form of a fiber, the transmittance is obtained by combining both the portion that passes through the Kevlar and the portion that passes through the air layer. As can be seen from FIG. 5, a loss of about 7 dB in total occurred near the wavelength of 650 nm (the UV transmission with the lowest transmission loss among the coating members had a transmission loss of 1.7 dB at 650 nm (a transmittance of about 70%)). ).

  6 shows the bending of the leakage power of 650 nm when the optical fiber cord used in FIG. 5 is inputted with visible light (using an LD light source) of 3 mW and wavelength of 650 nm and communication light of 1 mW and wavelength of 1550 nm. It is a figure showing a diameter and bending loss dependence (1 rotation winding). The optical power that can be seen in a place with indoor lighting (500 lx) was 1 μW (thus, the power of the light source for general fiber continuity check is around 1 mW, so the transmittance of the covering member is 0.1% or more. Is considered necessary). As can be seen from FIG. 6, a visible optical power can be obtained with a bending diameter of 8 mm or less, while no bending loss occurs in the communication light. Therefore, it can be seen that the optical fiber can be visually checked without affecting the communication.

  Further, FIG. 7 shows the dependency of the light leakage power on the cord length (position from the input end of the optical fiber cord for performing the core line comparison). The cable has a bending diameter of 5mm or more and a visible cord length of 50m or more. It can be applied to cables between cables in optical facilities.

  Moreover, the numerical value shown in this embodiment (FIGS. 3-6 etc.) is an example, and the application range of this invention is not limited to this range. As the light source, in addition to the LD, a He-Ne laser, a Ti sapphire laser, an argon laser, an LED, a dye laser, a fiber Raman laser, a fiber laser, or the like can be used. As for the optical coupler, in addition to the fiber coupler, a dielectric multilayer type, a spatial coupling, an optical waveguide, and the like can be used.

[Second Embodiment]
FIG. 8A shows the configuration of the optical fiber cord according to the second embodiment of the present invention, the light source connected thereto, and the optical coupler, and FIG. 8B shows the configuration of the second embodiment of the present invention. The cross-sectional view of such an optical fiber cord is shown. As shown in FIG. 8A, an optical coupling portion (fiber coupler) 32 is connected to an optical fiber cord 31 using PCF. The optical coupler unit 32 includes a plurality of optical connectors (or fused portions) 33 and a visible light source (wavelength 550 nm) 34, and the optical fiber cord 31 is located at a predetermined code length from the optical connector (or fused portion) 33. Is provided with a bending portion 35 for light leakage.

  As shown in FIG. 8B, the optical fiber cord 31 is the same as the configuration in FIG. 1 except that the air holes 23 are PCFs arranged in a double ring with 8 holes. Description is omitted. The optical coupler 32 was a fiber type optical coupler, the visible light source 34 was a laser diode having a wavelength of 550 nm, and the input power to the optical fiber cord was 3 mW. The characteristics of various materials and the light leakage characteristics at the time of imparting curvature of various wavelengths are the same as those in the first embodiment.

  FIG. 9 shows the dependency of the light leakage power on the cord length (position from the input end of the optical fiber cord for performing the core line contrast). The light leakage power is the maximum light receiving power at the curved position. The bending was performed at 4 mmφ, 5 mmφ, and 8 mmφ with one turn. As can be seen from FIG. 9, even when the cord length is 4 mφ and the cord length is 50 m or more, it is possible to contrast the cores by visual recognition under room lighting. In addition, when glass with a refractive index higher than the host glass of the fiber (Ge-doped, particle system: 2 μm) is mixed in the optical fiber cladding as a scatterer, it is 5 dB, and a 7 × 7 × 1 μm aluminum piece in the UV coating. The light reception level that can be seen under room lighting has decreased by 3 dB when mixed with aluminum and 3.5 dB when mixed with 7 x 7 x 1 µm aluminum pieces in the outer sheath of the cord. This is probably because scattered light was collected to some extent due to the presence of the scatterer.

  The numerical values shown in this embodiment (FIG. 9, scatterer size, etc.) are only examples, and the scope of application of the present invention is not limited to this range. As the light source, in addition to the LD, a He-Ne laser, a Ti sapphire laser, an argon laser, an LED, a dye laser, a fiber Raman laser, a fiber laser, or the like can be used. As the optical coupler, in addition to the fiber coupler, a dielectric multilayer type, a spatial coupling, an optical waveguide, and the like can be used. Examples of the scattering material include various metals (gold, platinum, aluminum, nickel alloy, etc.), various glasses (phosphorus, lead, aluminum, zinc-added glass, etc.), and those using strain of glass.

[Third embodiment]
FIG. 10A shows the configuration of an optical fiber cord according to the third embodiment of the present invention, a light source connected thereto, and an optical coupler, and FIG. 10B shows the configuration of the third embodiment of the present invention. The cross-sectional view of such an optical fiber cord is shown. As shown in FIG. 10A, an optical coupler unit (fiber coupler) 42 is connected to an optical fiber cord 41 using HAF. The optical coupler unit 42 includes a plurality of optical connectors (or fused portions) 43 and a near-infrared light source (wavelength 1000 nm) 44. The optical fiber cord 41 has a predetermined cord length from the optical connector (or fused portion) 43. The bend imparting part 45 for light leakage is provided at the position. The bend imparting unit 45 is provided with a core wire contrast device 46.

  As shown in FIG. 10B, the optical fiber cord 41 is the same as the configuration in FIG. 1 except that the reference light is near-infrared light 47, and the description is omitted with the same reference numerals. The optical coupler 42 is a fiber type optical coupler, the near infrared light source 44 is a laser diode with a wavelength of 1000 nm modulated at a frequency of 270 Hz, and the average input power to the optical fiber cord is 2 mW. The characteristics of various materials and the light leakage characteristics at the time of bending of various wavelengths are the same as in the third embodiment, and the light leakage at the time of bending does not leak near-infrared light (communication light) in the mid-wavelength range, similar to visible light. Even in the case, near-infrared light having a short wavelength leaks.

  FIG. 11 shows the dependency of the light leakage power on the cord length (position from the input end of the optical fiber cord for performing the core line contrast). The light leakage power is the maximum light receiving power at the curved position. The bending was performed at 4 mmφ, 5 mmφ, and 8 mmφ with one turn. A cord contrast device capable of receiving light with a wavelength of 1100 nm up to an optical power of 0.1 μW was used. As can be seen from the figure, light can be received even with a cord length of 500 m. Further, in the present embodiment, since the reference light is modulated, it greatly contributes to power saving, control accuracy, and avoidance of the influence of external light.

  Moreover, the numerical value shown by this embodiment is an example, and the application range of this invention is not limited to this range. As the light source, in addition to the LD, a He-Ne laser, a Ti sapphire laser, an argon laser, an LED, a dye laser, a fiber Raman laser, a fiber laser, or the like can be used. As the optical coupler, in addition to the fiber coupler, a dielectric multilayer type, a spatial coupling, an optical waveguide, and the like can be used.

  It is also possible to estimate the bending radius to some extent accurately from the bending loss ratio by using leaked light having a plurality of wavelengths. As for the modulation of the control light, various applications such as work instructions can be made by attaching various information to the signal and monitoring it with a cord contrast device.

[Fourth Embodiment]
FIG. 12 shows a configuration of an optical fiber cord, a light source connected to the optical fiber cord, an optical coupler, and a core contrast device according to the fourth embodiment of the present invention. As shown in FIG. 12, an optical coupler unit (fiber coupler) 52 is connected to an optical fiber cord 51 using HAF wired in a communication station. The optical coupling unit 52 includes a plurality of optical connectors (or fused portions) 53 and a two-wavelength light source (wavelength 650 nm + 1650 nm) 54, and the optical fiber cord 51 is positioned at a predetermined code length from the optical connector (or fused portion) 53. Is provided with a bending portion 55 for light leakage. An optical fiber cord 57 using SMF is connected by an optical connector (or fused portion) 56 to the end of the optical fiber cord 51 inside and outside the communication station. A bend imparting portion 58 is provided outside the communication station of the optical fiber cord 57, and a core wire contrast device 59 is provided in the bend imparting portion 58.

  The optical coupler is a fiber type optical coupler, and the light source is a two-wavelength light source that combines a light source that generates continuous light with a wavelength of 650 nm (optical power 3 mW) and a light source that generates modulated light with a wavelength of 1650 nm modulated at a frequency of 270 Hz. Met. In the present embodiment, assuming that the portion up to the optical fiber cord 51 is an in-house facility and the optical fiber cord 57 is connected to the rear end as an outside transmission line, two wavelengths (inside use 650 nm, outside use: 1650 nm) The optical fiber cords were input and the optical fiber cords could be used to control the cords. The inside HAF optical fiber cord 51 is 5 m from the input end at a bending diameter of 4 mm and the optical power is 5 μW, and the outside SMF optical fiber cord 57 is 5 km from the input end using a normal optical fiber contrast. 8 μW was received, and it was shown that the inside and outside of the center can be simultaneously controlled by using a two-wavelength light source.

  Note that the present invention is not limited to the above-described embodiment as it is, and can be embodied by modifying the constituent elements without departing from the scope of the invention in the implementation stage. Further, various inventions can be formed by appropriately combining a plurality of constituent elements disclosed in the embodiment. For example, some components may be deleted from all the components shown in the embodiment. Furthermore, you may combine suitably the component covering different embodiment.

  21 ... Core, 22 ... Hole layer, 23 ... Hole, 24 ... UV coating, 25 ... Kevlar, 26 ... Outer cord coating.

Claims (10)

An optical fiber cord using an optical fiber in which the light propagation part or core is surrounded by a plurality of holes and light in the wavelength range of 380 to 1200 nm can propagate through the gaps between the holes,
A covering member is provided so as to cover the optical fiber,
An optical fiber cord, wherein a covering member that allows light in a wavelength range of 380 to 1200 nm to pass through is used as the covering member. The optical fiber cord according to claim 1,
As the covering member, using a covering member that has a transmittance of 0.1% or more and 70% or less in a wavelength range of 380 to 1200 nm when light passes through the covering member in the cross-sectional direction,
An optical fiber cord comprising a covering member comprising at least one of a UV coating, a strength retaining material, and an outer coating of the cord as the covering member. The optical fiber cord according to claim 2,
An optical fiber cord comprising particles that scatter light having a wavelength range of 380 to 1200 nm in at least one of a UV coating, a strength-holding material, and an outer coating. In the optical fiber cord according to claim 1, 2, or 3,
When the optical fiber cord is bent, at least one of the light in the wavelength range of 380 to 1200 nm among the light propagating through the optical fiber is leaked, and the light having a wavelength exceeding 1200 nm is not leaked. An optical fiber cord. The optical fiber cord according to claim 4, wherein
When the optical fiber cord is bent with a radius of 5 mm, at least one of the light in the wavelength range of 380 to 1200 nm out of the light propagating through the optical fiber is leaked, and the light with a wavelength exceeding 1200 nm is not leaked. An optical fiber cord characterized by that. The optical fiber cord according to claim 4 or 5,
An optical fiber cord comprising an optical coupler that couples light having a wavelength range of 380 to 1200 nm to a light propagation portion or a core of the optical fiber cord. The optical fiber cord according to claim 6, wherein
An optical fiber cord comprising an optical coupler that multiplexes light having a wavelength range of 380 to 1200 nm without affecting signal light propagating through a light propagation portion or core of the optical fiber cord. The optical fiber cord according to claim 6 or 7,
An optical fiber cord, wherein a light source that emits light having a wavelength of 380 to 1200 nm and 1300 to 1700 nm or more or modulated light is connected. The optical fiber cord according to any one of claims 1 to 8,
An optical fiber cord, characterized in that a fiber optic cord is provided, and a fiber optic cord is provided to bend the optical fiber cord to detect a power or modulation signal of light having a wavelength range of 380 to 1200 nm. An optical fiber cord core-line contrast method using an optical fiber in which a light propagation part or core is surrounded by a plurality of holes and light in a wavelength range of 380 to 1200 nm can propagate through the gaps of the holes,
The optical fiber cord is bent and at least one of the wavelengths in the wavelength range of 380 to 1200 nm out of the light propagating through the optical fiber is leaked, and the light having a wavelength exceeding 1200 nm is not leaked. A method for contrasting optical fiber cords, comprising: performing contrast.

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