CN214540116U - Decoherence optical fiber - Google Patents

Abstract

The utility model relates to an optical fiber technology field especially relates to a decoherence optic fibre. The utility model discloses a decoherence optic fibre, including the optic fibre body, the optic fibre body includes cylindric fibre core body, and the fibre core body is twisted reverse at random for the unit according to certain length along its axial, should twist reverse to use the dabber of fibre core body to twist reverse as the axis of rotation. The utility model discloses the coherence of transmission light can be disturbed, realizes the output of the flat light of broad spectrum, satisfies the demand to broadband light source such as fiber gyroscope, and simple structure, easily realizes, and is with low costs.

Description

Decoherence optical fiber

Technical Field

The utility model belongs to the technical field of the optic fibre, specifically relate to a decoherence optic fibre.

Background

The broad spectrum flat light refers to a light beam with light intensity uniformly distributed in a section of broad spectrum in the laser transmission direction, and is widely applied to the fine processing fields of optical fiber gyroscopes, optical fiber sensing systems, optical fiber passive device tests, wavelength division multiplexing device tests, EDFA tests and the like due to uniform energy distribution. The wide-spectrum flat light has the characteristics of wide spectrum, stable power and uniform energy distribution, can meet the requirements of the light source of the optical fiber gyroscope, and is the main light source of the gyroscope.

At present, flat-top light sources used in the fiber-optic gyroscope mainly have two types: a spontaneous amplified radiation source (ASE) and a superluminescent light emitting diode light Source (SLD). The ASE light source is the main stream, can work in the whole C + L wave band, can reach 1530nm-1605nm, and has excellent wide spectrum characteristics. In addition, since the internal coherence of the ASE light source is weaker than that of the SLD, the spectral distribution is closer to a rectangle (whereas the distribution of the SLD is more gaussian), and the effect of applying the ASE light source to the fiber-optic gyroscope is better. Finally, the ASE light source can easily realize larger output power through an external control circuit, and has wider application range and stronger practicability.

Meanwhile, the operating spectrum of the ASE light source is wide, and the spectral flatness of the full bandwidth of the ASE light source is not ideal. The flatness is mainly limited by the coherence degree in the light emitting process of the light source, the coherence degree between photons is reduced, and the flatness of an output light field or the stability of light intensity can be correspondingly improved.

Experiments show that when laser is transmitted in the optical fiber, the coherence of the laser can be greatly eliminated by correspondingly processing the optical fiber, so that the flatness of the spectrum is improved. The existing treatment mode of the optical fiber changes the working environment of the optical fiber in an infiltration mode so as to eliminate coherence, but the mode has complex process and is not easy to realize, does not meet the requirements of the optical fiber gyroscope equipment on a light source, and is not applied.

Disclosure of Invention

An object of the present invention is to provide a decoherence optical fiber for solving the above existing technical problems.

In order to achieve the above object, the utility model adopts the following technical scheme: the decoherence optical fiber comprises an optical fiber body, wherein the optical fiber body comprises a cylindrical fiber core body, the fiber core body is randomly twisted by taking a certain length as a unit along the axial direction of the fiber core body, and the twisting is performed by taking a core shaft of the fiber core body as a rotation shaft.

Further, the random twist includes a twist direction random and a twist angle random.

Further, the core body has a twist angle per cm along its axial direction of between 10 and 60 degrees.

Further, the fiber core body is made of a glass material or a plastic material.

Furthermore, the optical fiber body further comprises an outer cladding layer, and the outer cladding layer is wrapped outside the fiber core body.

Further, the optical fiber connector further comprises a support wire, wherein the optical fiber body is spirally wound around the support wire, and the thread pitches along the winding direction are randomly distributed.

Further, the support wire is an elastic cord.

Further, the support wire is cylindrical and has a diameter of 2-10 mm.

Further, the thread pitch is 2-15 mm.

Further, still include the mounting, the mounting is fixed optical fiber body and support wire rod each other.

The utility model has the advantages of:

the utility model discloses the coherence of transmission light can be disturbed well, realizes the output of the flat light of broad spectrum, satisfies the demand to broadband light source such as fiber gyroscope, and simple structure, easily realizes, and is with low costs.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed to be used in the description of the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without creative efforts.

FIG. 1 is a schematic diagram of a fiber core structure according to an embodiment of the present invention;

FIG. 2 is a block diagram of an embodiment of the present invention;

FIG. 3 is a diagram showing the polarization state of polarized light of a laser pointer passing through a conventional optical fiber;

fig. 4a and 4b are polarization state diagrams of polarized light of the laser pen passing through the optical fiber structure of the present invention at different times.

Detailed Description

To further illustrate the embodiments, the present invention provides the accompanying drawings. The accompanying drawings, which are incorporated in and constitute a part of this disclosure, illustrate embodiments of the invention and, together with the description, serve to explain the principles of the embodiments. With these references, one of ordinary skill in the art will appreciate other possible embodiments and advantages of the present invention. Elements in the figures are not drawn to scale and like reference numerals are generally used to indicate like elements.

The present invention will now be further described with reference to the accompanying drawings and detailed description.

As shown in fig. 1 and 2, an incoherent optical fiber includes an optical fiber body 1, the optical fiber body 1 includes an outer cladding and a cylindrical core body 11 wrapped in the outer cladding, the core body 11 is a core of an existing conventional optical fiber, the core body 11 may be a glass core, a plastic core, or the like, and the core body 11 may be a single-mode core or a multimode core.

The core body 11 is randomly twisted in units of a certain length in the axial direction thereof, the twisting being performed with the core axis of the core body 11 as the rotation axis, thereby forming a processed core body 11'.

The random twist means that the twist of each unit is different and does not form a periodic structure, for example, the first unit is twisted by 40 degrees clockwise, the second unit is twisted by 45 degrees clockwise, the third unit is twisted by 30 degrees clockwise, and the fourth unit is twisted by 40 degrees … degrees counterclockwise, so that irregular twist is formed. By the random torsion structure, different and irregular (random) stress surfaces are generated on the axial surface of the fiber core, the coherence of transmitted light is disturbed, and the output of the wide-spectrum flat light is realized.

Preferably, in this embodiment, the random twist includes random twist direction and random twist angle, so that the interference cancellation is better, but not limited thereto.

Preferably, in this embodiment, the core body 11 is formed by a unit of 1 cm, but not limited thereto, the torsion angle of the core body 11 per cm length along the axial direction thereof is 10 to 60 degrees, which not only ensures the effect of changing the coherence, but also does not break the core body 11 and affect the light permeability.

In this embodiment, the outer cladding is the outer cladding of the conventional optical fiber, and the specific structure can refer to the prior art, which is not described in detail.

Further, in the present embodiment, the optical fiber module further includes a support wire 2, and the optical fiber body 1 is spirally wound around the support wire 2, and the pitches in the winding direction are randomly distributed. The random distribution of the screw pitches means that the screw pitches are different in size along the winding direction and do not have periodicity, namely, are irregularly distributed. And further, different stress surfaces are generated by randomly bending the axial surface of the fiber core, so that the coherence of transmitted light is more thoroughly disturbed, and the output of wide-spectrum flat light is realized.

Preferably, in this embodiment, the supporting wire 2 is cylindrical, which is easy to implement, and the curvature of the optical fiber body 1 after being spirally wound is relatively gentle, so that the optical fiber core body 11 is not broken and the light transmittance thereof is not affected. But is not limited thereto, and in some embodiments, the support wire 2 may also be prismatic, or the like.

Preferably, in this embodiment, the supporting wire 2 is soft, and can achieve a certain bending, so as to be convenient for use, but not limited thereto, and in some embodiments, the supporting wire 2 may also be a hard supporting wire.

In this embodiment, the supporting wire 2 is an elastic cord, which has good toughness and low cost, but not limited thereto, and in other embodiments, the supporting wire 2 may also be made of other materials such as plastic and metal.

Preferably, in this embodiment, the diameter of the supporting wire 2 is 2-10mm, which not only ensures the polarization effect, but also does not affect the light transmittance, and does not break the core of the optical fiber body 1.

Preferably, in this embodiment, the pitch is 2-15mm, which not only ensures that the polarization effect is well performed, but also does not affect the light transmittance.

In this embodiment, still include the mounting, the mounting is fixed optical fiber body 1 and support wire 2 each other, avoids optical fiber body 1 to remove the deformation.

In this embodiment, the fixing member is made of epoxy resin, which is easy to implement and low in cost, but not limited thereto, and in other embodiments, the fixing member may be wrapped and fixed by an elastic sleeve or a heat shrinkable tube.

After the fixing, two ends 12 and 13 of the optical fiber body 1 are reserved as optical fiber interfaces, so that the optical fiber connector is convenient and flexible to disassemble.

And (3) experimental verification:

use the laser pen as the light source, through ordinary optic fibre and process the utility model discloses an optic fibre structure output tests polarization property. Because the laser pen is linearly polarized light, after being transmitted by a common optical fiber, the polarization direction deflects by a certain angle, but is still linearly polarized light, as shown in fig. 3; after the output of the optical fiber structure of the present invention, the polarization direction is completely random, the polarization state is also changed, and the line polarization (as shown in fig. 4a) and the elliptical polarization (as shown in fig. 4b) can be randomly outputted. Namely the utility model discloses the coherence of transmission light can be disturbed well, the output of the flat light of broad spectrum is realized, the demand to broadband light source such as satisfying fiber gyroscope, and simple structure easily realizes, and is with low costs.

While the invention has been particularly shown and described with reference to a preferred embodiment, it will be understood by those skilled in the art that various changes in form and detail may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.

Claims (10)

1. An optical decoherence fiber comprising a fiber body including a cylindrical core body, characterized in that: the core body is randomly twisted along the axial direction of the core body by a certain length as a unit, and the twisting is performed by using a core shaft of the core body as a rotation shaft.

2. The decoherence optical fiber of claim 1, wherein: the random twist includes a twist direction random and a twist angle random.

3. The decoherence optical fiber of claim 1, wherein: the core body has a twist angle of between 10 and 60 degrees per centimeter of length along its axial direction.

4. The decoherence optical fiber of claim 1, wherein: the fiber core body is made of glass materials or plastic materials.

5. The decoherence optical fiber of claim 1, wherein: the optical fiber body further comprises an outer cladding layer, and the outer cladding layer is wrapped outside the fiber core body.

6. The decoherence optical fiber of any one of claims 1 to 5, wherein: the optical fiber module further comprises a supporting wire, wherein the optical fiber body is spirally wound around the supporting wire and is randomly distributed along the pitch of the winding direction.

7. The decoherence optical fiber of claim 6, wherein: the supporting wire is an elastic rope.

8. The decoherence optical fiber of claim 6, wherein: the supporting wire is cylindrical and has a diameter of 2-10 mm.

9. The decoherence optical fiber of claim 8, wherein: the thread pitch is 2-15 mm.

10. The decoherence optical fiber of claim 6, wherein: the optical fiber fixing device further comprises a fixing piece, and the optical fiber body and the supporting wire are fixed to each other through the fixing piece.

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