KR101717760B1 - Self-protection multi-core optical fiber amplifier - Google Patents

Abstract

A multi-core optical fiber amplifier according to an embodiment of the present invention includes a multi-core optical fiber including a first core doped with a gain medium, a second core separated from the first core, An auxiliary light source for inputting the auxiliary signal light to the second core, and a pump light source for inputting the pump light to the multi-core optical fiber.

Description

[0001] The present invention relates to a self-protection multi-core optical fiber amplifier,

The disclosed invention relates to a self-protecting multi-core optical fiber amplifier. More particularly, the present invention relates to a multi-core optical fiber amplifier for inputting a main beam to a first core of a multi-core optical fiber and inputting auxiliary signal light to a second core.

An optical fiber amplifier is an optical amplifier that amplifies an optical signal without changing an electrical signal at a level of light. In particular, the optical amplifier includes an optical fiber as an amplification medium. In the optical fiber amplifier, the amplification function can utilize the stimulated raman scattering of germanium (Ge) added to glass, which is the main component of the optical fiber, or the stimulated emission effect of the rare earth element added to the optical fiber . Among them, the optical fiber amplifier using Er: Erbium ion, which is a kind of rare earth element, has an amplifiable wavelength band of 1550 nm and coincides with a low loss region of the optical fiber. In addition, since the lifetime of the Er ions is as long as 10 ms, high efficiency amplification (40 dB) and low distortion characteristics can be obtained, it has become the cornerstone of Wavelength Division Multiplexing (WDM) that forms the mainstream of optical communication. On the other hand, optical fiber amplifiers are widely used not only in the optical communication field but also in the industrial optical fiber laser field. Fiber optic amplifiers have been used to develop high output optical fiber lasers, and fiber lasers are widely used in industrial and medical applications.

SUMMARY OF THE INVENTION The present invention provides a multi-core optical fiber amplifier including a first core receiving a main beam and a second core receiving auxiliary signal light.

A multi-core optical fiber amplifier according to an embodiment of the present invention includes:

At least one first core added with a gain medium, at least one second core provided apart from the first core, a first clad layer surrounding the first core and the second core, and a second clad layer surrounding the first core, A multi-core optical fiber including a second clad layer surrounding the first clad layer;

At least one main resonator for inputting the excitation light to the first core;

At least one auxiliary light source for inputting auxiliary signal light to the second core;

At least one pump light source for inputting the pump light to the multi-core optical fiber;

A main output unit for outputting the main beam; And

And an auxiliary output unit for outputting the auxiliary signal light to the outside.

And an advertiser provided between the main emission unit and the main output unit to prevent the light reflected from the main output unit from being reversed.

And a WDM coupler for coupling the main and auxiliary light sources to the multi-core optical fiber.

And an optical coupler coupling the pump light to the multi-core optical fiber.

The main output unit may further include a collimator.

The gain medium may be at least one selected from the group consisting of Yb, Er, Th, and Nd.

The second core may be formed of glass or plastic.

The diameter of the first core may be 1 to 40 탆.

The diameter of the second core may be 1 to 40 탆.

The distance between the first core and the second core may be 1.1 to 5 times the sum of the radius of the first core and the radius of the second core.

The auxiliary signal light can absorb the excitation energy of the gain medium when the intensity of the main beam inputted to the first core is less than the reference intensity or when the main beam is not inputted to the first core.

The gain medium is Yb and the wavelength of the main beam and the auxiliary signal are in a range of 1020 nm to 1120 nm and the wavelength of the main beam and the wavelength of the auxiliary signal may be different from each other.

The gain medium may be erbium (Er), the wavelength of the main beam and the auxiliary signal may be 1520 nm to 1610 nm, and the wavelength of the main beam and the wavelength of the auxiliary signal may be different from each other.

The gain medium may be thulium (Tm), the wavelength of the main beam and the auxiliary signal may be 1880 nm to 2020 nm, and the wavelength of the main beam and the wavelength of the auxiliary signal may be different from each other.

The gain medium may be ytterbium (Yb), the wavelength of the main beam may be 1064 nm, and the wavelength of the auxiliary signal may be 1035 nm.

The gain medium may be erbium (Er), the wavelength of the main beam may be 1550 nm, and the wavelength of the auxiliary signal may be 1530 nm.

The gain medium may be thulium (Tm), the wavelength of the main beam may be 1960 nm, and the wavelength of the auxiliary signal may be 1920 nm.

The wavelength of the pump light may be 900 nm to 990 nm.

The wavelength of the pump light may be any value selected from 915 nm, 940 nm, 965 nm and 975 nm.

The present invention relates to a self-protection type optical fiber amplifier having a multi-core optical fiber including a first core for inputting a main beam and a second core for inputting auxiliary signal light, wherein the main beam is not inputted to the first core, The auxiliary signal light can absorb the excitation energy from the gain medium of the first core. Therefore, a nonlinear effect that may occur when the excitation light is not input to the first core or when the excitation light input to the first core is weaker than the reference intensity, for example, stimulated Brillouin scattering (SBS) Amplified spontaneous emission, and the like, thereby protecting the multi-core optical fiber amplifier of the present invention by itself.

1 is a schematic cross-sectional view of a multi-core optical fiber included in a self-protecting multi-core optical fiber amplifier according to an embodiment of the present invention.
2 is a schematic cross-sectional view of another multi-core optical fiber provided in a self-protecting multi-core optical fiber amplifier according to an embodiment of the present invention.
3 is a schematic cross-sectional view of another multi-core optical fiber provided in a self-protecting multi-core optical fiber amplifier according to an embodiment of the present invention.
4 is a schematic cross-sectional view of another multi-core optical fiber provided in a self-protecting multi-core optical fiber amplifier according to an embodiment of the present invention.
5 is a schematic diagram of a self-protecting multi-core optical fiber amplifier according to an embodiment of the present invention.
6 is a schematic diagram of a self-protecting multi-core optical fiber amplifier according to another embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a multi-core optical fiber amplifier of the present invention will be described in detail with reference to the accompanying drawings. In the following drawings, like reference numerals refer to like elements, and the size of each element in the drawings may be exaggerated for clarity and convenience of explanation.

1 is a schematic cross-sectional view of a multicore optical fiber 100 provided in a self-protecting multi-core optical fiber amplifier according to an embodiment of the present invention.

Referring to FIG. 1, a multicore optical fiber 100 according to the present embodiment includes a first core 10 doped with a gain medium, a second core 20 provided apart from the first core 10, A first cladding layer 30 surrounding the second core 10 and a second core 20 and a second cladding layer 40 surrounding the first cladding layer 30.

The first core 10 may be formed of glass or plastic and may be doped with a gain medium. The gain medium may be a rare earth element and may include, for example, ytterbium (Yb), erbium (Er), thulium (Tm), neodymium (Nd), and combinations thereof. The diameter of the first core 10 may be about 1 to about 40 占 퐉, and the main beam from the master oscillator may be input. The wavelength of the excitation light may be a value in the range of 1020 nm to 1120 nm when the gain medium is ytterbium (Yb). For example, the wavelength of the excitation light may be 1064 nm when the gain medium is Yb. If the gain medium is erbium (Er), the wavelength of the excitation light may be a value in the range of 1520 nm to 1610 nm. For example, the wavelength of the focused light may be 1550 nm when the gain medium is erbium (Er). In addition, the wavelength of the focused light may be a value in the range of 1880 nm to 2020 nm when the gain medium is thulium (Tm). For example, the wavelength of the excitation light may be 1960 nm when the gain medium is thulium (Tm).

The second core 20 may be formed of glass or plastic and may not be doped with a gain medium. That is, the second core 20 may be formed only of glass or plastic to which no gain medium is added. The diameter of the second core 20 may be about 1 to about 40 micrometers, and auxiliary signal light may be input from the auxiliary light source. The wavelength of the auxiliary signal may be a value ranging from 1020 nm to 1120 nm when the gain medium doped in the first core 10 is Yb. For example, the wavelength of the auxiliary signal may be 1035 nm when the gain medium doped in the first core 10 is Yb. The wavelength of the auxiliary signal may be a value in the range of 1520 nm to 1610 nm when the gain medium doped in the first core 10 is erbium (Er). For example, the wavelength of the auxiliary signal may be 1530 nm when the gain medium doped in the first core 10 is erbium (Er). Also, the wavelength of the auxiliary signal light may be a value ranging from 1880 nm to 2020 nm when the gain medium doped in the first core 10 is thulium (Tm). For example, the wavelength of the auxiliary signal light may be 1920 nm when the gain medium doped in the first core 10 is thulium (Tm).

Here, the wavelength of the auxiliary signal light may be different from the wavelength of the main beam, and the wavelength of the auxiliary signal light may be smaller than the wavelength of the main beam. On the other hand, the radius of the first core 10 and second core radius of the first core 10, the distance (L) of 20 are separated from one another (d _1/2) and the batt (20) (d ₂ / 2) to be 1.1 times to 5 times the sum of the value _{((d 1 + d 2)} / 2).

The first cladding layer 30 surrounds the first core 10 and the second core 20 and may be formed of a material having a refractive index lower than that of the first core 10 and the second core 20. [ The first cladding layer 30 can receive the pump light from the pump light source, and the pump light can excite the doped gain medium in the first core 10, Can be absorbed by the main luminous flux passing through the light source 10. That is, the main beam passing through the first core 10 can be amplified by absorbing the excitation energy emitted from the gain medium. In addition, auxiliary signal light passing through the second core 20 can be amplified by absorbing excitation energy emitted from the gain medium, which will be described later. On the other hand, the diameter of the first cladding layer 30 may be about 100 탆 or more, and may be several hundred 탆.

The second cladding layer 40 surrounds the first cladding layer 30 and may be formed of a material having a refractive index lower than that of the first cladding layer 30. Therefore, the pump light input to the first cladding layer 30 can be totally reflected on the interface between the first cladding layer 30 and the second cladding layer 40 and travel along the first cladding layer 30.

1, the first core 10 and the second core 20 are arranged in parallel, and the arrangement of the first core 10 and the second core 20 is limited to this arrangement no. For example, the first core 10 may be provided at the center of the multicore optical fiber 100, and the second core 20 may be provided at the periphery of the first core 10. The first core 10 is provided at the center of the multicore optical fiber 100 and the second core 20 is spaced apart from the first core 10 to surround the periphery of the first core 10 in a spiral form Can be. In addition, the first core 10 and the second core 20 may be arranged in various forms.

When the excitation light is input to the first core 10, the excitation light can be amplified by absorbing the excitation energy from the excitation medium excited by the pump light. On the other hand, it can be expected that the auxiliary signal light will not be amplified because it proceeds through the second core 20 which is not doped with the gain medium. However, it can be experimentally confirmed that the intensity of the auxiliary signal light traveling through the second core 20 is actually measured. Also, theoretically, when the solution is obtained by using a waveguide propagation equation of an electromagnetic wave, it can be seen that the auxiliary signal light is amplified. This is because the main beam and the auxiliary signal proceed in the form of a photon beam, but also in the form of an electromagnetic wave. That is, the main beam and the auxiliary signal proceed through the first core 10 and the second core 20, respectively, but they can affect each other because they proceed while making an electromagnetic field. The auxiliary signal light travels through the second core 20 but progresses while forming an electromagnetic field around the second core 20 so that the coupling between the first core 10 around the second core 20 and the coupling Or interact with each other. That is, the auxiliary signal light can be amplified by advancing the second core 20 not doped with the gain medium but absorbing the excitation energy from the gain medium of the first core 10.

The degree of amplification of the auxiliary signal light is determined by the diameter d ₁ of the first core 10, the diameter d 2 of the second core 20 and the distance d ₂ between the first core 10 and the second core 20 The cross-sectional shape of the first core 10 and the second core 20, the arrangement form of the first core 10 and the second core 20, the intensity of the auxiliary signal light, can do. When the main beam is normally input to the first core 10, the degree to which the auxiliary signal light is amplified can be controlled so that the main beam can be amplified by a target amount. That is, the amount of excitation energy that can be absorbed by the auxiliary signal light from the gain medium of the first core 10 can be controlled through design parameter optimization, in order to amplify the main beam by the designed amount.

In the conventional optical fiber, when the signal light can not be normally inputted to the core of the optical fiber, for example, when the signal light is not activated because the light source of the signal light is not operated, or when the intensity of the signal light is smaller than the designed input intensity, Energy can cause nonlinear effects because the signal to be amplified is not sufficient. For example, the energy generated by simultaneous Brillouin scattering (SBS) can be reflected backward in the direction of the light source, and the amplification spontaneous emission (ASE) can be used for double Rayleigh scattering Back-Scattering (DRBS) may occur. This reverse process can damage all of the optical components on the optical path and can also make it difficult to determine which parts are damaged.

However, in the multicore optical fiber 100 according to the present embodiment, when the main beam can not be normally input to the first core 10, for example, the main beam may not be input at all because the main beam does not operate , The auxiliary signal light is input to the second core 20 even when the intensity of the incoming light is smaller than the designed input intensity, so that the energy excited by the pump light can amplify the auxiliary signal light, thereby suppressing the nonlinear effect . Therefore, it is possible to prevent the optical components from being damaged by the SBS or the DRBS which has been caused due to the signal light being not normally input to the optical fiber.

2 is a schematic cross-sectional view of another multi-core optical fiber 110 provided in a self-protecting multi-core optical fiber amplifier according to an embodiment of the present invention. The difference from the above-described multicore optical fiber 100 will be described in detail.

The multicore optical fiber 110 according to the present embodiment may include one first core 10 and two second cores 20 and 21 and the centers of the three cores 10, Respectively. However, the arrangement of the cores 10, 20, 21 is not limited to the one shown in Fig. The amplification degree of the auxiliary signal light input to the second core 20 and 21 is determined by the diameter d ₁ of the first core 10, the diameters d ₂ and d ₃ of the second core 20, (L ₁ , L ₂ ) between the first core 10 and the second core 20, 21, the cross-sectional shape of the first core 10 and the second core 20, 21, The arrangement of the two cores 20 and 21, and the input intensity of the auxiliary signal light. On the other hand, when the main beam is normally input to the first core 10, the degree to which the auxiliary signal is amplified can be controlled so that the main beam can be amplified by a target amount. The distance L ₁ between the first core 10 and the second core 20 is determined by the radius d _1/2 of the first core 10 and the radius d _1/2 of the second core 20 _2/2) to be 1.1 times to 5 times the sum of the value _{((d 1 + d 2)} / 2). The distance L ₂ between the first core 10 and the second core 21 is different from the radius d _1/2 of the first core 10 by the radius of the second core 21 It may be 1.1 times to 5 times the value _{((d 1 + d 2)} / 2) plus the (d _3/2).

The auxiliary signal light is inputted to the remaining second core 21 and is amplified even though the excitation light and the auxiliary signal light provided to the first core 10 and the second core 20 are not respectively input to the multicore optical fiber 110 of the present embodiment It is possible to suppress the nonlinear effect caused by the absence of an object to be amplified by the energy excited by the pump light, thereby preventing the damage of the optical components.

3 is a schematic cross-sectional view of another multi-core optical fiber 120 provided in a self-protecting multi-core optical fiber amplifier according to an embodiment of the present invention. The difference from the multi-core optical fibers 100 and 110 described above will be described in detail.

The multicore optical fiber 120 according to the present embodiment may include one first core 10 and two second cores 20 and 23. The first core 10 may include a plurality of multicore optical fibers 120, And the second cores 20 and 23 may be arranged on both sides of the first core 10 in parallel. That is, the two second cores 20 and 23 can be symmetrically arranged around the first core 10. Further, the first core 10 and the second cores 20, 23 may be arranged in parallel with each other. However, the configuration of the cores 10, 20, 23 is not limited to the configuration shown in FIG. 3, and various configurations are possible.

The amplification degree of the auxiliary signal light input to the second cores 20 and 23 is determined by the diameter d ₁ of the first core 10, the diameters d ₂ and d ₃ of the second cores 20 and 23, The distance L ₁ and L ₂ between the first core 10 and the second core 20 and 23, the cross-sectional shape of the first core 10 and the second core 20 and 23, And the second cores 20 and 23 and the input intensity of the auxiliary signal inputted to the second cores 20 and 23 can be controlled. On the other hand, when the main beam is normally input to the first core 10, the degree to which the auxiliary signal is amplified can be controlled so that the main beam can be amplified by a target amount. Here, the distance L ₁ between the first core 10 and the second core 20 is equal to the distance d _1/2 between the first core 10 and the second core 20 d _2/2) to be 1.1 times to 5 times the sum of the value _{((d 1 + d 2)} / 2). The distance L ₂ between the first core 10 and the second core 23 is different from the radius d _1/2 of the first core 10 by the radius of the second core 23 It may be 1.1 times to 5 times the value _{((d 1 + d 2)} / 2) plus the (d _3/2).

The auxiliary signal light is input to the remaining second core 23 and is amplified even though the excitation light and the auxiliary signal light provided to the first core 10 and the second core 20 are not respectively input to the multicore optical fiber 120 of the present embodiment It is possible to suppress the nonlinear effect caused by the absence of an object to be amplified by the energy excited by the pump light, thereby preventing the damage of the optical components.

4 is a schematic cross-sectional view of another multi-core optical fiber 130 provided in a self-protecting multi-core optical fiber amplifier according to an embodiment of the present invention. The difference from the multi-core optical fibers 100, 110, and 120 described above will be described in detail.

The multicore optical fiber 130 according to the present embodiment may include two first cores 10 and 15 and two second cores 20 and 25. The first cores 10 and 15 and the second cores 20, The cores 20 and 23 may be arranged to face each other, and the centers of the cores may be arranged in a square shape. However, the arrangement of the cores 10, 15, 20 and 25 is not limited to that shown in FIG. 4, and the cores 10, 15, 20 and 25 may be formed in a polygonal shape such as a rectangle, a rhombus, Lt; / RTI > The degree to which the auxiliary signal light input to the second cores 20 and 25 is amplified depends on the diameter of the first cores 10 and 15, the diameter of the second cores 20 and 25, The distance between the two cores 20 and 25, the cross-sectional shape of the first cores 10 and 15 and the second cores 20 and 25, the cross-sectional shapes of the first cores 10 and 15 and the second cores 20 and 25 And the input intensity of the auxiliary signal input to the second cores 20 and 25 can be controlled. On the other hand, when the main beam is normally input to the first core 10, 15, the degree of amplification of the auxiliary signal can be controlled so that the main beam can be amplified by a target amount.

Since the auxiliary signal light can be input to the remaining second cores 20 and 25 and amplified even if the main beam is not input to the first cores 10 and 15, It is possible to suppress the nonlinear effect caused by the absence of the object to be amplified and to prevent the damage of the optical parts.

5 is a schematic diagram of a self-protecting multi-core optical fiber amplifier 200 according to an embodiment of the present invention.

Referring to FIG. 5, the multi-core optical fiber amplifier 200 according to the present embodiment includes the multi-core optical fiber 100 shown in FIG. 1, a main optical fiber 210 An auxiliary light source 220 for inputting auxiliary signal light to the second core 20, a pump light source 250 for inputting the pump light to the multicore optical fiber 100, a main output unit 280 for outputting the main light, And an auxiliary output unit 290 for outputting the auxiliary signal light to the outside. The multi-core optical fiber amplifier 200 according to the present embodiment may further include an advertiser 240, a WDM coupler 230, an optical coupler 260, and the like.

The main resonator 210 may include a light source, an optical fiber doped with a gain medium, and a pump light source, although not shown in the figure. The wavelength of the main beam may be a value in the range of 1020 nm to 1120 nm when the gain medium is Yb, For example, it may be 1064 nm. If the gain medium is erbium (Er), the wavelength of the excitation light may be a value in the range of 1520 nm to 1610 nm, for example, 1550 nm. In addition, the wavelength of the excitation light may be a value ranging from 1880 nm to 2020 nm when the gain medium is thulium (Tm), and may be, for example, 1960 nm. Although FIG. 5 illustrates one main transmitter 210, the multi-core optical fiber amplifier 200 may include a plurality of main amplifiers. On the other hand, if the optical fiber 210 fails to operate normally, for example, if the optical fiber is cut off or if the optical source or the pump light source is damaged, the main beam may not be input to the first core 10.

The auxiliary light source 220 may be a light source such as a laser diode, a Q-switch resonator, or the like, and may input the auxiliary signal light to the second core 20. The wavelength of the auxiliary signal may be a value ranging from 1020 nm to 1120 nm when the gain medium doped in the first core 10 is Yb, for example, 1035 nm. The wavelength of the auxiliary signal may be a value in the range of 1520 nm to 1610 nm when the gain medium doped in the first core 10 is erbium (Er), for example, 1530 nm. The wavelength of the auxiliary signal may be a value ranging from 1880 nm to 2020 nm when the gain medium doped in the first core 10 is thulium (Tm), for example, 1920 nm. Here, the wavelength of the auxiliary signal light may be different from the wavelength of the main beam, and the wavelength of the auxiliary signal light may be smaller than the wavelength of the main beam. The auxiliary signal light travels through the second core 20 to which the gain medium is not added. However, since the auxiliary signal light proceeds in the form of an electromagnetic wave, it can absorb the excitation energy from the gain material of the first core 10. Although FIG. 5 illustrates one auxiliary light source 220, the multi-core optical fiber amplifier 200 may include a plurality of auxiliary light sources.

The wavelength division multiplexing (WDM) coupler 230 may connect the main optical fiber 210 and the auxiliary optical fiber 220 to the multicore optical fiber 100, that is, the first core 10 and the second core 20, respectively .

The advertiser 240 may be provided between the main transmitter 210 and the main output 280 to prevent the light reflected from the main output 280 from reversing and damaging the main transmitter 210 . Also, it is possible to prevent the auxiliary light source 220 and the pump light source 250 from being damaged by the reflected light. A plurality of advertisement planes 240 may be provided in the multicore optical fiber 100.

The pump light source 250 may input the pump light to the multicore optical fiber 100, and may include, for example, a laser diode or the like. The pump light source 250 can input the pump light to the first clad layer 30 of the multicore optical fiber 100. The pump light can be totally reflected from the interface between the first clad layer 30 and the second clad layer 40, And can proceed through the first cladding layer 30. The wavelength of the pump light may be any wavelength between 900 nm and 990 nm, for example, 915 nm, 940 nm, 965 nm or 975 nm. Although FIG. 5 illustrates one pump light source 250, the multi-core optical fiber amplifier 200 may include a plurality of pump light sources.

The optical coupler 260 may couple the pump light source 250 to the multicore optical fiber 100. In particular, the optical coupler 260 may connect the pump light source 250 to the first cladding layer 30.

The main output unit 280 may output the amplified main beam to the outside, and may further include a collimator. The collimator can enhance the straightness by condensing the main beam outputted from the collimator.

The auxiliary output unit 290 may output the amplified auxiliary signal light to the outside, and may further include a collimator. The collimator can enhance the directivity by condensing the output auxiliary signal light. The amplified auxiliary signal light can be used in devices requiring multiple wavelengths, for example the amplified main beam is for cutting and the amplified auxiliary signal can be used for marking.

In the case of the self-protection type multi-core optical fiber amplifier 200 according to the present embodiment, when the main beam is input to the first core 10, the main beam absorbs excitation energy from the gain medium excited by the pump light, . On the other hand, it can be expected that the auxiliary signal light will not be amplified because it proceeds through the second core 20 which is not doped with the gain medium. However, it can be experimentally confirmed that the intensity of the auxiliary signal light traveling through the second core 20 is actually measured. Also, theoretically, when the solution is obtained by using a waveguide propagation equation of an electromagnetic wave, it can be seen that the auxiliary signal light is amplified. This is because the main beam and the auxiliary signal proceed in the form of a photon beam, but also in the form of an electromagnetic wave. That is, the main beam and the auxiliary signal proceed through the first core 10 and the second core 20, respectively, but they can affect each other because they proceed while making an electromagnetic field. The auxiliary signal light travels through the second core 20 but progresses while forming an electromagnetic field around the second core 20 so that the coupling between the first core 10 around the second core 20 and the coupling Or interact with each other. That is, the auxiliary signal light can be amplified by advancing the second core 20 not doped with the gain medium but absorbing the excitation energy from the gain medium of the first core 10.

The degree of amplification of the auxiliary signal light is determined by the diameter d ₁ of the first core 10, the diameter d 2 of the second core 20 and the distance d ₂ between the first core 10 and the second core 20 And the distance L of the light emitting diode. On the other hand, when the main beam is normally input to the first core 10, the degree of amplification of the auxiliary signal light can be controlled so that the main beam can be amplified by a target amount.

In the conventional optical fiber amplifier, when the signal light can not be normally inputted to the core of the optical fiber, for example, when the signal light is not operated and the signal light intensity is lower than the designed input intensity, The generated energy can cause a nonlinear effect because there is not enough signal light to be amplified. For example, energy by simultaneous Brillouin scattering (SBS) can be reversed in the direction of the light source. This reverse process can damage all the optical components on the optical path, and it is also difficult to determine which part is damaged. Therefore, conventionally, when the optical component is damaged due to the nonlinear effect, the optical fiber amplifier has to be replaced, resulting in a large economic loss.

However, in the case of the self-protection type multi-core optical fiber amplifier 200 according to the present embodiment, when the main beam can not be normally input to the first core 10, for example, when the main beam 210 is operated The auxiliary signal light can be input from the auxiliary light source 220 to the second core 20 even if the input signal intensity is not inputted at all or the intensity of the incoming optical signal is smaller than the designed input intensity. Therefore, the energy excited by the pump light can amplify the auxiliary signal light. Therefore, it is possible to prevent the nonlinear effect that may occur due to no input of the main beam, and to prevent the optical components from being damaged.

6 is a schematic diagram of a self-protecting multi-core optical fiber amplifier 300 according to another embodiment of the present invention. The difference from the self-protection type multicore optical fiber amplifier 200 shown in FIG. 5 described above will be described in detail.

6, the multi-core optical fiber amplifier 300 according to the present embodiment includes the multi-core optical fiber 110 shown in FIG. 2, a main optical fiber 210 for inputting a main beam to the first core 10, Two auxiliary light sources 221 and 223 for inputting auxiliary signal lights to the two second cores 20 and 21, a pump light source 250 for inputting the pump light to the multicore optical fiber 110, A main output unit 280 output to the outside, and two auxiliary output units 291 and 293 each outputting the auxiliary signal light to the outside. The magnetic protection type multicore optical fiber amplifier 300 according to the present embodiment may further include an advertiser 240, a WDM coupler 230, and an optical coupler 260.

Unlike the multi-core optical fiber amplifier 200 shown in FIG. 5, the self-protecting multi-core optical fiber amplifier 300 according to the present embodiment includes two auxiliary light sources 221 and 223. In addition, the multicore optical fiber 110 also includes two second cores 20 and 21. In the case where the main beam is not normally input to the first core 10 and the auxiliary signal is not inputted to the second core 20 in the multicore optical fiber amplifier 200 due to the non-linear effect, Optical components can be damaged. However, the self-protected multi-core optical fiber amplifier 300 according to the present embodiment further includes one auxiliary light source 223 and one second core 21, 2 core 21 as shown in FIG. Therefore, the energy excited by the pump light can amplify the other auxiliary signal inputted from the auxiliary light source 223. Accordingly, the nonlinear effect caused by the input of the main beam and the auxiliary signal can be suppressed, and the damage of the optical components can be prevented.

The multi-core optical fiber amplifier of the present invention has been described with reference to the embodiments shown in the drawings in order to facilitate understanding of the present invention. However, those skilled in the art will appreciate that various modifications and equivalent It will be appreciated that other embodiments are possible. Accordingly, the true scope of the present invention should be determined by the appended claims.

10, 15: first core 20, 21, 23, 25:
30: first clad layer 40: second clad layer
100, 110, 120, 130: Multicore optical fiber
200, 300: Self-Protecting Multicore Fiber Amplifier
210: Primary incident light 220, 221, 223: Secondary light source
230: WDM combiner 240: Advertiser
250: pump light source 260: optical coupler
280: main output unit 290, 291, 293: auxiliary output unit

Claims (19)

At least one first core added with a gain medium, at least one second core provided apart from the first core, a first clad layer surrounding the first core and the second core, and a second clad layer surrounding the first core, A multi-core optical fiber including a second clad layer surrounding the first clad layer;
At least one main resonator for inputting the excitation light to the first core;
At least one auxiliary light source for inputting auxiliary signal light to the second core;
At least one pump light source for inputting the pump light to the multi-core optical fiber;
A main output unit for outputting the main beam; And
And an auxiliary output unit for outputting the auxiliary signal light to the outside. The method according to claim 1,
Further comprising an advertiser provided between the main transmitter and the main output unit to prevent the light reflected from the main output unit from being reversed. The method according to claim 1,
And a WDM coupler for coupling the main and auxiliary light sources to the multi-core optical fiber. The method according to claim 1,
And an optical coupler coupling the pump light to the multi-core optical fiber. The method according to claim 1,
Wherein the main output unit further includes a collimator. The method according to claim 1,
Wherein the gain medium is at least one selected from the group consisting of Yb, Er, Th, and Nd. The method according to claim 1,
And the second core is formed of glass or plastic. The method according to claim 1,
Wherein the first core has a diameter of 1 to 40 占 퐉. The method according to claim 1,
And the second core has a diameter of 1 to 40 占 퐉. The method according to claim 1,
Wherein the distance between the first core and the second core is 1.1 to 5 times the sum of the radius of the first core and the radius of the second core. The method according to claim 1,
Wherein the auxiliary signal light absorbs the excitation energy of the gain medium when the intensity of the main beam is less than a reference intensity or when the main beam is not input to the first core, Protected Multicore Fiber Amplifier. The method according to claim 1,
Characterized in that the gain medium is Yb and the wavelength of the main beam and the auxiliary signal is in a range of 1020 nm to 1120 nm and the wavelength of the main beam and the wavelength of the auxiliary signal are different from each other, Core optical fiber amplifier. The method according to claim 1,
Wherein the gain medium is erbium (Er), the wavelength of the main excitation light and the auxiliary signal light is 1520 nm to 1610 nm, and the wavelength of the main excitation light and the wavelength of the auxiliary signal light are different from each other. Fiber optic amplifier. The method according to claim 1,
Wherein the gain medium is thulium (Tm), the wavelength of the main beam and the auxiliary signal are 1880 nm to 2020 nm, and the wavelength of the main beam and the wavelength of the auxiliary signal are different from each other. Fiber optic amplifier. The method according to claim 1,
Wherein the gain medium is Yb, the wavelength of the main beam is 1064 nm, and the wavelength of the auxiliary signal is 1035 nm. The method according to claim 1,
Wherein the gain medium is erbium (Er), the wavelength of the main beam is 1550 nm, and the wavelength of the auxiliary signal is 1530 nm. The method according to claim 1,
Wherein the gain medium is thulium (Tm), the wavelength of the main beam is 1960 nm, and the wavelength of the auxiliary signal is 1920 nm. The method according to claim 1,
Wherein the wavelength of the pump light is 900 nm to 990 nm. The method according to claim 1,
Wherein the wavelength of the pump light is a value selected from among 915 nm, 940 nm, 965 nm, and 975 nm.

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