CN201188005Y

CN201188005Y - Bidirectional light path-sharing distributed optical fibre interferometer

Info

Publication number: CN201188005Y
Application number: CNU2008200854401U
Authority: CN
Inventors: 任尚今
Original assignee: NINGBO NUOKE ELECTRONIC TECHNOLOGY DEVELOPMENT CO LTD
Current assignee: Zhejiang nuko Dsy technology Ltd
Priority date: 2008-04-22
Filing date: 2008-04-22
Publication date: 2009-01-28
Anticipated expiration: 2018-04-22

Abstract

The utility model discloses a bidirectional common-path distribution type optical fiber interferometer which mainly comprises an optical fiber splitter, an optical fiber isolator and a transduction optical fiber. The optical fiber isolator and the transduction optical fiber which are identical together form a Mach-Zehnder interferometer with equally long arms; the light coming from a laser source of an external system passes through the optical isolator, is then divided into two ways with identical light intensity by the optical fiber splitter and is then input to the two terminals of the interferometer through different fibers. In order to enable the additional phases of the interference signals of the two ways to be identical, after entering the splitter constituting the interferometer from the forward and the reverse directions, the light has to be directly connected through a straight through arm. The bidirectional common-path distribution type optical fiber interferometer can be used for external safety alarm and location of optical cables and opto-electrical composite cables, provides a basic optical structure for the real-time safety alarm and correct location of the communication cables, does not need any construction to the prior optical fiber network, is not only applicable to the land environment but also applicable to the underwater environment, and has simple use and wide application environment.

Description

Two-way light path distribution type fiber-optic interferometer altogether

Technical field

The utility model belongs to the photoelectron technology field, particularly a kind of two-way light path distribution type fiber-optic interferometer altogether.

Background technology

Fibre optic interferometer is a kind of basic optical structure in Fibre Optical Sensor and the detection technique, is the gordian technique that realizes high sensitivity and high-acruracy survey.Existing traditional fibre optic interferometer structure mainly contains Michelson interferometer, Fabry-Perot interferometer, ring cavity interferometer and Mach-Zehnder interferometer, adopt end input, the check configuration of one end output, the optical interference signals that output terminal obtains is the integration along all disturbance quantities of fiber distribution, the disturbance information on the specific range can't be separated, therefore distributed detection can't be realized.

The utility model content

The purpose of this utility model is to provide a kind of range information that optical fiber is gone up the disturbance of certain position along the line that can provide for the deficiency that solves above-mentioned technology, to realize the two-way light path distribution type fiber-optic interferometer altogether of distributed measurement.

In order to achieve the above object, a kind of two-way light path distribution type fiber-optic interferometer altogether that the utility model is designed mainly comprises optical fibre light splitting device, fibre optic isolater and sensor fibre.Two identical optical fibre light splitting devices and sensor fibre such as constitute jointly at the Mach-Zehnder interferometer of brachium; From the light of the LASER Light Source of external system through behind the optoisolator, adopt the optical fibre light splitting device to be divided into aplanatic two-way, distribute and be input to the two ends of interferometer through different fiber, in order to make the additional phase error unanimity of two-way interference signal, after the light of positive and negative both direction enters the optical splitter that constitutes interferometer, must directly link to each other by straight-through arm.The two-way interference signal is got back to receiving end by different optical fiber, obtains the interference signal of two-way waveform unanimity, is used for detecting.

Described optical fibre light splitting device of the present utility model can adopt reflection film coated type optical fibre light splitting device.

Just constituted the two-way light path fibre optic interferometer altogether of polarization irrelevant by said structure, signal output waveform unanimity under the situation of external disturbance from the output of Mach-Zehnder interferometer two ends, the inconsistent two groups of interference signals of time delay, by measuring the time delay of two groups of signals, can tell the position realization Distributed Detection that optical fiber is gone up the somewhere disturbance along the line.

A kind of two-way light path distribution type fiber-optic interferometer altogether provided by the utility model, two-way light path fibre optic interferometer altogether based on the polarization irrelevant of Mach-Zehnder interferometer, utilize the phasic difference between the two-way interference signal to provide the range information that optical fiber is gone up the disturbance of certain position along the line, to realize distributed measurement.

This two-way light path distribution type fiber-optic interferometer altogether adopts the two-way interferometer structure of light path altogether, and simple compact, cost is low, easily practicability.Utilize the optical fibre light splitting device of commercial polarization irrelevant, can have highly conforming interferometer system by batch making.Interferometer optical fiber length can arbitrarily be adjusted according to real system, can adapt to the different situations and the requirement of application system.Can make up detection system based on newly-built communications optical cable or original communications optical cable, system adopts full light structural, has the characteristics of essential safety, can be applicable to all kinds of hazardous environments.

The two-way light path distribution type fiber-optic interferometer altogether of the resulting a kind of polarization irrelevant of the utility model can be used for the external safety early-warning and the location of optical cable, photoelectricity composite cable, and the actual time safety of communications optical cable is reported to the police and accurately located provides optics basic structure.

The two-way light path distribution type fiber-optic interferometer altogether of the polarization irrelevant that the utility model provides, need not on existing fiber optic network, to do any construction, only need to connect according to optical texture of the present utility model at the node two ends of communication optical fiber, can reach the design function of system, therefore, system of the present utility model is not only applicable to terrestrial environment, is applicable to underwater environment yet, make it to use simple, suitable environment is wide.

Description of drawings

Fig. 1 is the utility model embodiment 1 principle of work structural representation;

Fig. 2 is embodiment 2 structural representations;

Fig. 3 is a concrete Application Example block diagram of the present utility model.

Embodiment

The utility model will be further described in conjunction with the accompanying drawings below by embodiment:

Embodiment 1:

The two-way light path distribution type fiber-optic interferometer altogether of present embodiment design, it comprises optoisolator, Transmission Fibers, optical fibre light splitting device and sensor fibre.

As shown in Figure 1: the optical fibre light splitting device 4 of polarization irrelevant and 5 and communications optical cable in

optical fiber

61,62 constitute the Mach-Zehnder interferometers jointly; After entering into isolator 2 from the light of LASER Light Source from optical fiber 1, through the input end 311 of optical fibre light splitting device 3, respectively from

output terminal

312 and 321 outputs; The light of output terminal 312 enters fibre optic interferometer by the input end 411 of optical splitter 4, from output terminal 522 outputs of optical splitter 5, gets back to receiving end 81 through optical fiber 63; The light of output terminal 321 enters fibre optic interferometer by the input end 512 that optical fiber 64 is input to optical splitter 5, from output terminal 421 outputs of optical splitter 4, gets back to receiving end 82.

Embodiment 2:

The two-way light path distribution type fiber-optic interferometer altogether that present embodiment is described, its structure also can be as shown in Figure 2, the optical fibre light splitting device 4 of polarization irrelevant and 5 and communications optical cable in

optical fiber

61,62 common formations two-way light path distribution type fiber-optic interferometer altogether of the present utility model, after entering into isolator 2 from the light of LASER Light Source from optical fiber 1, through the input end 311 of optical fibre light splitting device 3, respectively from

output terminal

312 and 321 outputs; The light of output terminal 312 enters fibre optic interferometer by the input end 411 of optical splitter 4, and output terminal 512 outputs from optical splitter 5 are input to optical splitter 7 through optical fiber 64, get back to receiving end 81 from the output terminal 721 of optical splitter 7; The light of output terminal 321 is input to the input end 712 of optical splitter 7, and the input end 512 that is input to optical splitter 5 by optical fiber 64 enters fibre optic interferometer, from output terminal 421 outputs of optical splitter 4, gets back to receiving end 82.

Each element of present embodiment can adopt conventional products, now is described in detail as follows for example:

Optical fiber: the general optical communication single-mode fiber,

Optoisolator: isolation is greater than 30dB, and magnetic tape trailer is fine to be exported,

The optical fibre light splitting device: adopting reflection plated film device to carry out beam split, by the general single mode fiber input and output, can be 1 * 2 and 2 * 2 optical splitters, and splitting ratio can adopt 50: 50.

Embodiment 3:

As shown in Figure 3, present embodiment is described is that the two-way light path distribution type fiber-optic interferometer altogether of polarization irrelevant is at the external safety early-warning of optical cable, photoelectricity composite cable and the embodiment in the positioning system.

Front end sensing unit 2211, rear end sensing unit 2221 and communications optical cable 10 constitute the two-way light path distribution type fiber-optic interferometer altogether of polarization irrelevant according to the light channel structure of the utility model design, the two-way interference signal is by the pre-service of signal processing unit 3211, enter into control module 4211 and host server 11, realization is carried out incident to the security incident of the outside plant 12 of infringement optical cable on host server 11 feature identification and delay time signal extract, thereby realize early warning and location to the infringement incident.

Claims

1, a kind of two-way altogether light path distribution type fiber-optic interferometer mainly comprises optical fibre light splitting device, fibre optic isolater and sensor fibre, it is characterized in that two identical optical fibre light splitting devices and sensor fibre such as constitute jointly at the interferometer of brachium; From the light of the LASER Light Source of external system through behind the optoisolator, adopt the optical fibre light splitting device to be divided into aplanatic two-way, distributing is input to the two ends of interferometer through different fiber, after the light of positive and negative both direction enters the optical splitter that constitutes interferometer, directly link to each other by straight-through arm; The two-way interference signal is got back to receiving end by different optical fiber.

2, a kind of two-way light path distribution type fiber-optic interferometer altogether according to claim 1 is characterized in that described optical fibre light splitting device can adopt reflection film coated type optical fibre light splitting device.