JP2003131038A - Optical component, dispersion adjusting module, and optical communication system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a dispersion adjusting module, an optical component and the like in which dispersion characteristics is easily adjusted. SOLUTION: One end of a flexible member 110 is secured with a fixing member 130, while the other end is in contact with the tips of flexure supplying means 141 and 142. The tips of flexure supplying means 141 and 142 sandwich the other end of the flexible member 110, and a stress is applied to the flexible member 110 at the position of flex the flexible member 110. Related to an optical waveguide diffraction grating element 120, a Bragg grating is formed at an optical fiber as an optical waveguide, which is secured to the flexible member 110. It is so provided as to diagonally cross, at a position C, a neutral surface N in flexure of the flexible member 110 when a stress is applied by the flexure supplying means 141 and 142.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical component including an optical waveguide type diffraction grating element having an optical waveguide formed with a Bragg grating, a dispersion adjusting module including the optical component, and an optical communication including the dispersion adjusting module. It is about the system.

[0002]

2. Description of the Related Art An optical waveguide type diffraction grating element is one in which a grating by refractive index modulation is formed over a predetermined range along the longitudinal direction of an optical waveguide (for example, an optical fiber) and propagates through this optical waveguide. It is possible to selectively reflect or give a loss to the light of a specific wavelength among the lights that are generated. Among them, the optical waveguide type diffraction grating element in which the chirped Bragg grating in which the grating spacing of the refractive index modulation changes along the longitudinal direction is formed in the optical waveguide, the Bragg condition is set at each position in the longitudinal direction of the grating. Since it can reflect light having a wavelength that satisfies the above, it can be used as one component of a dispersion adjustment module that adjusts chromatic dispersion of light in a certain fixed wavelength range. The dispersion adjustment module is provided in a repeater or the like in an optical communication system that performs optical transmission using signal light, and can compensate chromatic dispersion in an optical fiber transmission line.

A dispersion adjusting module including an optical waveguide type diffraction grating element in which a chirped Bragg grating is formed in an optical waveguide preferably has variable dispersion characteristics and is adjustable. For example, each dispersion adjustment module mass-produced with a certain standard can be installed in a repeater or the like, and the dispersion characteristics of the dispersion adjustment module can be adjusted according to the dispersion characteristics of the optical fiber transmission line that is the object of dispersion compensation. The dispersion adjustment module can be manufactured at low cost. Also, if the dispersion characteristics of the optical fiber transmission line subject to dispersion compensation fluctuate due to temperature changes, the dispersion characteristics of the dispersion adjustment module can be adjusted according to the fluctuations, so the wavelength of the optical fiber transmission line is always adjusted. The dispersion can be suitably compensated by the dispersion adjustment module.

As an optical component including an optical waveguide type diffraction grating element that can be used as a dispersion adjusting module having such variable dispersion characteristics, Japanese Patent Laid-Open No. 2000-235170 and reference "MM Ohn, et al.," Dispersion " variabl
e fiber Bragg grating using a piezoelectric stac
K ", Electronics Letters, Vol.32, No.21 (1996)" is known.

In the device disclosed in the above publication, a grating is formed over a certain range along the longitudinal direction of an optical fiber which is an optical waveguide, and a plurality of micro heaters are in contact with the optical fiber within the certain range. It is provided. Then, a temperature distribution is formed in the optical fiber in the above-mentioned fixed range by the plurality of micro-heaters, whereby the effective refractive index of the grating at each position is adjusted, and the dispersion characteristic at the time of reflection of light in this grating is Adjusted.

Further, in the device described in the above-mentioned Ohn document, a grating is formed over a certain range along the longitudinal direction of an optical fiber which is an optical waveguide, and a plurality of piezoelectric elements are formed in the certain range. It is provided in contact with the optical fiber. A stress distribution is formed in the optical fiber within the certain range by the plurality of piezo elements, whereby the grating spacing of the grating at each position is adjusted, and the dispersion characteristic at the time of reflection of light in this grating is adjusted. To be done.

[0007]

However, the one described in the above publication or Ohn's document requires controlling a plurality of micro-heaters or a plurality of piezo elements, which is not easy to control. Therefore, it is not easy to adjust the dispersion characteristic when light is reflected by the grating.

The present invention has been made in order to solve the above problems, and provides a dispersion adjusting module in which the dispersion characteristics can be easily adjusted, an optical component suitably used in this dispersion adjusting module, and this dispersion adjusting module. An object is to provide an optical communication system including the same.

[0009]

The optical component according to the present invention comprises:
(1) a flexible member having flexibility, (2) a first bending imparting means for bending the flexible member by applying stress to the flexible member in a first direction, and (3) A Bragg grating is formed on an optical waveguide provided so as to obliquely intersect a neutral plane when the flexible member is deflected when stress is applied by the first deflection imparting means. And an optical waveguide type diffraction grating element that Bragg-reflects light having a specific wavelength that has propagated through and is incident by a Bragg grating, and propagates the reflected light in a direction opposite to that at the time of incidence. Further, a dispersion adjusting module according to the present invention includes the optical component according to the present invention described above, and reflects light by a waveguide type diffraction grating element included in the optical component to adjust wavelength dispersion of the light. Is characterized by.

According to the optical component of the present invention, when the flexible member bends due to the action of the first bending imparting means, it is provided so as to intersect the neutral plane when the flexible member bends. In the optical waveguide type diffraction grating element thus provided, tensile stress acts along one of the longitudinal directions along the longitudinal direction from the intersection with the neutral plane to generate tensile strain, and the other on the other side from the intersection along the longitudinal direction. Compressive stress acts to generate compressive strain. As a result, in the optical waveguide type diffraction grating element, the Bragg wavelength becomes longer depending on the degree of extensional strain at each position on one side of the intersection, and the Bragg wavelength becomes longer at each position on the other side of the intersection depending on the degree of compressive strain. The wavelength becomes shorter. The longitudinal distributions of the strain and the Bragg wavelength in the optical waveguide type diffraction grating element (the positive and negative of the inclination, the absolute value of the inclination) depend on the bending direction and the bending degree of the flexible member. The band, reflectance and dispersion characteristics of the light reflected by the waveguide type diffraction grating element change according to the bending direction and the bending degree of the flexible member. further,
The group delay characteristic of the dispersion adjusting module according to the present invention including the optical component also changes according to the bending direction and the bending degree of the flexible member.

Further, the optical component according to the present invention further comprises second bending imparting means for bending the flexible member by applying stress to the flexible member in a second direction different from the first direction. It is preferable that the neutral plane at the time of bending of the flexible member when stress is applied by the second bending applying means is parallel to the optical waveguide. In this case, the action of the first bending imparting means adjusts the group delay characteristic at the time of reflection in the optical waveguide type diffraction grating element, and the action of the second bending imparting means causes the optical waveguide type diffraction grating element to function. The band at the time of reflection is also adjusted.

The flexible member included in the optical component according to the present invention is preferably made of resin, and is formed by molding an optical waveguide type diffraction grating element with the resin. It is suitable. It is preferable that the flexible member includes a first member and a second member that sandwich and fix the optical waveguide type diffraction grating element, and a long groove portion for fixing the optical waveguide type diffraction grating element. It is preferable to have In any of these cases, it is suitable for fixing the optical waveguide type diffraction grating element to a desired position with respect to the flexible member.

Further, it is preferable that the flexible member included in the optical component according to the present invention has a cross-sectional area and / or a rigidity varying along the longitudinal direction. In this case, the distribution of the tensile stress or the compressive stress in the optical waveguide type diffraction grating element when the flexible member is bent can be made suitable, and the reflection of light in the optical waveguide type diffraction grating element can be achieved. The characteristics can be made suitable.

An optical component adjusting method according to the present invention is a method for adjusting the optical component according to the present invention, which monitors dispersion characteristics of light reflected by an optical waveguide type diffraction grating element and monitors the dispersion characteristic. Based on the result, the amount of bending of the flexible member by the first bending applying means is adjusted. By adjusting the optical component in this way, it is possible to preferably adjust the reflection characteristic of light in the optical waveguide type diffraction grating element included in the optical component, and to adjust the light in the dispersion adjustment module including this optical component. The transmission characteristics can be adjusted appropriately.

An optical communication system according to the present invention is an optical communication system that performs optical transmission using signal light, and includes the above-mentioned dispersion adjusting module according to the present invention. It is characterized in that chromatic dispersion is compensated. According to this optical communication system, since the chromatic dispersion of the optical fiber transmission line is compensated by the dispersion adjusting module, high quality signal light transmission can be performed. Further, since the dispersion characteristic of the dispersion adjusting module can be adjusted, this dispersion adjusting module can be mass-produced with a certain standard, and after being installed, the dispersion of the optical fiber transmission line which is the object of dispersion compensation can be adjusted. The dispersion characteristics can be adjusted according to the characteristics. Therefore, the dispersion adjustment module can be manufactured at low cost, and the optical communication system can be manufactured at low cost. Also, if the dispersion characteristics of the optical fiber transmission line subject to dispersion compensation fluctuate due to temperature changes, the dispersion characteristics of the dispersion adjustment module can be adjusted according to the fluctuations, so the wavelength of the optical fiber transmission line is always adjusted. The dispersion can be suitably compensated by the dispersion adjustment module.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described in detail below with reference to the accompanying drawings. In the description of the drawings, the same elements will be denoted by the same reference symbols, without redundant description.

(First Embodiment) First, a first embodiment of the optical component according to the present invention will be described. FIG. 1 is a diagram showing a configuration of an optical component 100 according to the first embodiment. The optical component 100 shown in this figure includes a flexible member 110, an optical waveguide type diffraction grating element 120, a fixing member 130, and bending imparting means 141 and 142.

The flexible member 110 is flexible, one end side of which is fixed by a fixing member 130, and the other end side of which is in contact with the respective tips of the bending imparting means 141 and 142. The flexible member 110 is made of, for example, fiber reinforced plastic, resin, metal or the like. The tip end of each of the flexure imparting means 141 and 142 has a flexible member 1.
The other end sides of 10 are sandwiched between each other, and stress can be applied to the flexible member 110 at that position to bend the flexible member 110. For example, when the bending imparting means 141 above the flexible member 110 pushes the other end side of the flexible member 110, the flexible member 110 is bent upward in a convex shape. On the other hand, the bending imparting means 142 below the flexible member 110 pushes the other end side of the flexible member 110,
The flexible member 110 bends in a downward convex shape. For example, a solenoid coil, a direct drive motor, a screw, or the like is preferably used as each of the bending imparting means 141 and 142.

The optical waveguide type diffraction grating element 120 is one in which a Bragg grating is formed in an optical fiber which is an optical waveguide. Light having a specific wavelength that has propagated through the optical fiber and is incident is Bragg-reflected by the Bragg grating. The reflected light is propagated in the opposite direction to the incident direction. The optical waveguide type diffraction grating element 120 may have a uniform refractive index modulation grating interval along the longitudinal direction, or a chirp with a refractive index modulation grating interval varying along the longitudinal direction. It may be a Tobragg grating.

The optical waveguide type diffraction grating element 120 is fixed to the flexible member 110, and the bending imparting means 14 is provided.
Flexible member 1 when stressed by 1,142
It is provided so as to obliquely intersect at a position C with respect to the neutral plane N at the time of bending of 10. Therefore, when the flexible member 110 is bent by the action of the bending imparting means 141, 142, tensile stress acts on the optical waveguide type diffraction grating element 120 along the longitudinal direction on one side from the position C, On the other side of the position C, compressive stress acts along the longitudinal direction.

The flexible member 110 may have a uniform cross-sectional area and rigidity along the longitudinal direction.
It is preferable that the cross-sectional area and / or the rigidity change along the longitudinal direction. By doing so, the distribution of the tensile stress or the compressive stress in the optical waveguide type diffraction grating element 120 when the flexible member 110 is bent can be made suitable.

2 and 3 are explanatory views of a method of fixing the optical waveguide type diffraction grating element 120 to the flexible member 110 in the optical component 100 according to the first embodiment. When the flexible member 110 is made of resin, it is preferable that the optical waveguide type diffraction grating element 120 is molded and fixed in the resin, but as shown in FIG. 2 or FIG. It is also preferable that the optical waveguide type diffraction grating element 120 is fixed to the member 110.

In the fixing method shown in FIG. 2, the flexible member 110 comprises a first member 111 and a second member 112,
The optical waveguide type diffraction grating element 120 is arranged along the long groove portion 111A formed in the first member 111, and the first member 111
And the second member 112 are pasted together to form the flexible member 110.
The optical waveguide type diffraction grating element 120 is fixed with respect to. In this case, the bonding surface between the first member 111 and the second member 112 includes a line in the flexible member 110 where the optical waveguide type diffraction grating element 120 is to be provided, and the flexible member 11
It is provided so as to intersect the neutral plane N of 0. Thereby, the optical waveguide type diffraction grating element 120 arranged in the long groove portion 111A on the bonding surface is provided so as to obliquely intersect the neutral surface N.

In the fixing method shown in FIG. 3, the flexible member 110 comprises a first member 113 and a second member 114,
The optical waveguide type diffraction grating element 120 is arranged along the long groove portion 113A formed in the first member 113, and the first member 113
And the second member 114 are pasted together to form the flexible member 110.
The optical waveguide type diffraction grating element 120 is fixed with respect to. In this case, the bonding surface of the first member 113 and the second member 114 includes the line in which the optical waveguide type diffraction grating element 120 is to be provided in the flexible member 110, and the flexible member 11
It is provided so as to be orthogonal to the neutral plane N of 0. Accordingly, the optical waveguide type diffraction grating element 120 arranged in the long groove portion 113A on the bonding surface is provided so as to intersect the neutral surface N at an angle.

Next, an embodiment of the dispersion adjustment module according to the present invention will be described. FIG. 4 is a configuration diagram of the dispersion adjustment module 10 according to the first embodiment. The dispersion adjustment module 10 shown in this figure includes the optical component 100 and the optical circulator 190 according to the first embodiment. The optical circulator 190 has a first terminal 191, a second terminal 192, and a third terminal 193.
The light input to the terminal 191 is output from the second terminal 192,
The light input to the second terminal 192 is output from the third terminal 193. At the second terminal 192 of the optical circulator 190,
The optical waveguide type diffraction grating element 120 of the optical component 100 is connected.

The light input from the input end 10a of the dispersion adjusting module 10 is the first terminal 1 of the optical circulator 190.
It is inputted to 91 and outputted from the second terminal 192, and the optical component 1
00 to the optical waveguide type diffraction grating element 120. Of the light input to the optical waveguide type diffraction grating element 120, the light of a specific wavelength that satisfies the Bragg condition is reflected by the optical waveguide type diffraction grating element 120 and input to the second terminal 192 of the optical circulator 190 to enter the third terminal. Output from 193,
It is output from the output terminal 10b of the dispersion adjustment module 10.

If the optical waveguide type diffraction grating element 120 is a chirped Bragg grating, the light transmitted from the input end 10a of the dispersion adjusting module 10 to the output end 10b is a Bragg grating at each position in the longitudinal direction of the chirped Bragg grating. The light has a wavelength range that satisfies the conditions and has a group delay characteristic according to the dispersion characteristic when the light is reflected by the chirped Bragg grating.

FIG. 5 shows an optical component 100 according to the first embodiment.
FIG. 5 is a diagram illustrating an operation example of the dispersion adjustment module 10. In this operation example, the position C intersecting the neutral plane N is assumed to be at the center of the region where the refractive index modulation of the optical waveguide type diffraction grating element 120 is formed. FIG. 11A shows the longitudinal distribution of strain in the optical waveguide type diffraction grating element 120. FIG. 6B shows the longitudinal distribution of the Bragg wavelength in the optical waveguide type diffraction grating element 120. The same figure (c)
Shows the wavelength dependence of the light transmittance from the input end 10a to the output end 10b of the dispersion adjustment module 10. The same figure (d)
Shows the wavelength dependence of the group delay time when light is transmitted from the input end 10a to the output end 10b of the dispersion adjustment module 10.

As shown in FIG. 5A, when the flexible member 110 is bent by the action of the bending imparting means 141, 142, it obliquely intersects with the neutral plane N at the position C at the time of the bending. In the optical waveguide type diffraction grating element 120 provided as described above, tensile stress acts along the longitudinal direction on one side from the center position C to generate extension strain, and on the other side from the position C, the longitudinal direction. A compressive stress acts along the line to generate compressive strain. As a result, as shown in FIG. 6B, in the optical waveguide type diffraction grating element 120, the Bragg wavelength becomes longer at each position on one side of the position C according to the degree of extensional strain, and the Bragg wavelength becomes longer than that at the position C. At each position on the side of, the Bragg wavelength becomes shorter depending on the degree of compressive strain. Distortion and Bragg wavelength distributions in the optical waveguide type diffraction grating element 120 in the longitudinal direction (positive and negative inclinations,
The absolute value of the inclination) corresponds to the bending direction and the bending degree of the flexible member 110. Since there is almost no distortion at the position C, the Bragg wavelength λ _{C at the} position C hardly changes.

Then, as shown in FIG. 3C, the input end 10a to the output end 10b of the dispersion adjusting module 10 are connected.
The transmission band and the transmittance of the light transmitted to the flexible member 1 are
It changes depending on the bending direction of 10 and the degree of bending.
That is, when the range of the Bragg wavelength along the longitudinal direction of the optical waveguide type diffraction grating element 120 is wide (solid line in FIG. 7B), the light transmitted from the input end 10a to the output end 10b of the dispersion adjusting module 10 is transmitted. , The transmission band becomes wider, and the transmittance in that band becomes smaller (solid line in FIG. 7C). On the contrary, if the range of the Bragg wavelength along the longitudinal direction of the optical waveguide type diffraction grating element 120 becomes narrow ((b) in the figure).
(Dashed line in the middle), the transmission band of light transmitted from the input end 10a to the output end 10b of the dispersion adjusting module 10 becomes narrower,
The transmittance in that band increases (broken line in FIG. 7C). At this time, since the position C is at the center of the region where the refractive index modulation of the optical waveguide type diffraction grating element 120 is formed,
The transmission band of the dispersion adjusting module 10 is centered on the Bragg wavelength λ _C at this position C.

Further, as shown in FIG. 3D, the group delay time when light is transmitted from the input end 10a to the output end 10b of the dispersion adjusting module 10 also depends on the direction of bending of the flexible member 110 and It changes according to the degree of bending. That is, even if the transmission band changes, the maximum value and the minimum value of the group delay time in that band hardly change, so that if the transmission band is wide, the wavelength dependence of the group delay time becomes gentle. On the other hand, if the transmission band becomes narrower, the wavelength dependence of the group delay time becomes sharper (broken line in (d)). There is almost no distortion at the position C, and the Bragg wavelength λ _{C at} that position _C
Of the Bragg wavelength λ _C , the group delay time hardly changes.

FIG. 6 shows an optical component 100 according to the first embodiment.
FIG. 9 is a diagram illustrating another operation example of the dispersion adjustment module 10. In this operation example, the position C intersecting the neutral plane N
Is on the fixed end side of the center of the region where the refractive index modulation of the optical waveguide type diffraction grating element 120 is formed. FIG. 11A shows the longitudinal distribution of strain in the optical waveguide type diffraction grating element 120. FIG. 6B shows the longitudinal distribution of the Bragg wavelength in the optical waveguide type diffraction grating element 120. FIG. 6C shows the wavelength dependence of the light transmittance from the input end 10 a to the output end 10 b of the dispersion adjustment module 10. FIG. 3D shows the wavelength dependence of the group delay time when light is transmitted from the input end 10 a to the output end 10 b of the dispersion adjusting module 10.

As shown in FIG. 4A, when the flexible member 110 is bent by the action of the bending imparting means 141, 142, it obliquely intersects the neutral plane N at the position C at the time of bending. In the optical waveguide type diffraction grating element 120 provided as described above, tensile stress acts along the longitudinal direction on one side from the center position C to generate extension strain, and on the other side from the position C, the longitudinal direction. A compressive stress acts along the line to generate compressive strain. As a result, as shown in FIG. 6B, in the optical waveguide type diffraction grating element 120, the Bragg wavelength becomes longer at each position on one side of the position C according to the degree of extensional strain, and the Bragg wavelength becomes longer than that at the position C. At each position on the side of, the Bragg wavelength becomes shorter depending on the degree of compressive strain. Distortion and Bragg wavelength distributions in the optical waveguide type diffraction grating element 120 in the longitudinal direction (positive and negative inclinations,
The absolute value of the inclination) corresponds to the bending direction and the bending degree of the flexible member 110. Since there is almost no distortion at the position C, the Bragg wavelength λ _{C at the} position C hardly changes. Further, since the position C is located closer to the fixed end than the center of the region where the refractive index modulation of the optical waveguide type diffraction grating element 120 is formed, the amount of change in strain (that is, change in Bragg wavelength on the fixed end side from this position C). Amount) is small, and the amount of change in strain (that is, the amount of change in Bragg wavelength) is large on the free end side from this position C.

Then, as shown in FIG. 3C, the input end 10a to the output end 10b of the dispersion adjusting module 10 are connected.
The transmission band and the transmittance of the light transmitted to the flexible member 1 are
It changes depending on the bending direction of 10 and the degree of bending.
That is, when the range of the Bragg wavelength along the longitudinal direction of the optical waveguide type diffraction grating element 120 is wide (solid line in FIG. 7B), the light transmitted from the input end 10a to the output end 10b of the dispersion adjusting module 10 is transmitted. , The transmission band becomes wider, and the transmittance in that band becomes smaller (solid line in FIG. 7C). On the contrary, if the range of the Bragg wavelength along the longitudinal direction of the optical waveguide type diffraction grating element 120 becomes narrow ((b) in the figure).
(Dashed line in the middle), the transmission band of light transmitted from the input end 10a to the output end 10b of the dispersion adjusting module 10 becomes narrower,
The transmittance in that band increases (broken line in FIG. 7C). At this time, since the position C is at the center of the region where the refractive index modulation of the optical waveguide type diffraction grating element 120 is formed,
The transmission band of the dispersion adjusting module 10 is centered on the Bragg wavelength λ _C at this position C. Also,
Since the position C is located closer to the fixed end than the center of the region where the refractive index modulation of the optical waveguide type diffraction grating element 120 is formed, the transmission band of the dispersion adjusting module 10 includes the Bragg wavelength λ _C at this position C. necessarily not centered on wavelength lambda _C, small changes in the bandwidth on one side than the wavelength lambda _C, the change in bandwidth is large on the other side than the wavelength lambda _C.

Further, as shown in FIG. 3D, the group delay time when light is transmitted from the input end 10a to the output end 10b of the dispersion adjusting module 10 also depends on the bending direction of the flexible member 110. It changes according to the degree of bending. That is, even if the transmission band changes, the maximum value and the minimum value of the group delay time in that band hardly change, so that if the transmission band is wide, the wavelength dependence of the group delay time becomes gentle. On the other hand, if the transmission band becomes narrower, the wavelength dependence of the group delay time becomes sharper (broken line in (d)). There is almost no distortion at the position C, and the Bragg wavelength λ _{C at} that position _C
Of the Bragg wavelength λ _C , the group delay time hardly changes.

Next, examples of the optical component 10 according to the first embodiment will be described. FIG. 7 is a diagram illustrating a positional relationship between the flexible member 110 and the optical waveguide type diffraction grating element 120 in the optical component 10 of the example. In the embodiment, the length of the flexible member 110 between the fixed end (position fixed by the fixing member 130) and the free end (position where stress is applied by the bending imparting means 141, 142) is 55 mm.
And The thickness of the flexible member 110 at the fixed end is 5 m.
and the thickness of the flexible member 110 at the free end is 2 m.
m. In addition, the grating spacing of the refractive index modulation in the optical waveguide type diffraction grating element 120 is assumed to be uniform along the longitudinal direction.

In the first embodiment, the optical waveguide type diffraction grating element 1 is used.
20 is at a position where the distance d from the lower surface of the flexible member 110 is 5 mm at the fixed end, and the flexible member 1 is at the free end.
It was assumed to be at the position of the lower surface of 10. In the second embodiment, the optical waveguide type diffraction grating element 120 is located at a position where the distance d from the lower surface of the flexible member 110 is 4 mm at the fixed end,
The free end is located on the lower surface of the flexible member 110. In the third embodiment, the optical waveguide type diffraction grating element 120 is used.
Is at a position where the distance d from the lower surface of the flexible member 110 is 3 mm at the fixed end, and the flexible member 110 is at the free end.
It is assumed to be located on the lower surface of the. In addition, in the comparative example, the optical waveguide type diffraction grating element 120 is attached to the upper surface of the flexible member 110.

FIG. 8 is a diagram showing the longitudinal distribution of strain in the optical waveguide type diffraction grating element 120 in the case of the first embodiment. FIG. 9 is a diagram showing the longitudinal distribution of strain in the optical waveguide type diffraction grating element 120 in the case of the second embodiment.
FIG. 10 shows an optical waveguide type diffraction grating element 1 in the case of Example 3.
It is a figure which shows the longitudinal distribution of the strain in 20. Further, FIG. 11 is a diagram showing the longitudinal distribution of strain in the optical waveguide type diffraction grating element 120 in the case of the comparative example. Here, in each of the examples and the comparative examples, +1 mm displacement and -1 mm displacement were applied to the free end of the flexible member 110 by the flexure imparting means 141 and 142, respectively.

As shown in FIG. 11, in the comparative example, when the free end of the flexible member 110 is displaced by +1 mm and when the free end of the flexible member 110 is displaced by -1 mm. In and, the longitudinal distribution of strain in the optical waveguide type diffraction grating element 120 was relatively flat, and the inclination was almost unchanged. On the other hand, FIGS.
As shown in FIG.
When the displacement of +1 mm is applied to the free end of 0 and when the displacement of −1 mm is applied to the free end of the flexible member 110, the inclination of the longitudinal distribution of strain in the optical waveguide type diffraction grating element 120 is The signs were different from each other.

Particularly, in each of Examples 2 and 3, the longitudinal distribution of strain in the optical waveguide type diffraction grating element 120 was excellent in linearity. The tensile stress in the optical waveguide type diffraction grating element 120 when the flexible member 110 is bent by changing either or both of the cross-sectional area and the rigidity along the longitudinal direction of the flexible member 120. Alternatively, the distribution of compressive stress can be made suitable, and the shape of the longitudinal distribution of strain in the optical waveguide type diffraction grating element 120 can be made desired.

FIG. 12 is a diagram showing the longitudinal distribution of strain in the optical waveguide type diffraction grating element 120 in the case of the third embodiment. Here, the deflection imparting means 141, 142 causes a displacement of −1.00 mm at the free end of the flexible member 110, −
A displacement of 0.50 mm and a displacement of -0.25 mm were given respectively. As shown in this figure, the flexible member 11
The amount of displacement at the free end of 0 (that is, the flexible member 110
The inclination of the longitudinal distribution of strain in the optical waveguide type diffraction grating element 120 was different from each other according to the amount of bending. That is, the larger the absolute value of the displacement amount at the free end of the flexible member 110, the larger the optical waveguide type diffraction grating element 12 is.
The absolute value of the slope of the longitudinal distribution of strain at 0 was large. However, even if the inclination of the longitudinal distribution of strain in the optical waveguide type diffraction grating element 120 changes, there was almost no strain at position C on the neutral plane N.

As described above, in the optical component 100 and the dispersion adjusting module 10 according to the first embodiment, only the flexible member 110 is bent so that the optical waveguide type diffraction grating element 120 intersects the neutral plane N. Since it is possible to adjust the slope of the dispersion characteristic, it is easy to adjust the dispersion characteristic.

(Second Embodiment) Next, a second embodiment of the optical component according to the present invention will be described. FIG. 13 is a diagram showing the configuration of the optical component 200 according to the second embodiment. The optical component 200 shown in this figure includes a flexible member 210, an optical waveguide type diffraction grating element 220, a fixing member 230, and flexure imparting means 241 to 244. In the figure, an xyz orthogonal coordinate system is shown for convenience of description. The figure (a) is a figure when it sees in parallel with the y-axis direction, and the figure (b) is a figure when seeing it in parallel with the x-axis direction. The z-axis is parallel to the longitudinal direction of the flexible member 210. The x-axis is the flexible member 21 due to the bending imparting means 241 and 242.
It is parallel to the direction of stress applied to the zero free end. The y-axis is parallel to the direction of the stress applied to the free end of the flexible member 210 by the flexure imparting means 243 and 244.

The flexible member 210 has flexibility, one end side thereof is fixed by a fixing member 230, and the other end side thereof is in contact with each tip of the bending imparting means 241 to 244. The flexible member 210 is made of, for example, fiber reinforced plastic or resin. The tip ends of the bending imparting means 241 and 242 sandwich the other end side of the flexible member 210, and at that position, a stress parallel to the x-axis direction is applied to the flexible member 210 to bend the flexible member 210. The elastic member 210 can be bent. Further, the tips of the bending imparting means 243 and 244 respectively have the flexible member 21.
The other end sides of 0 are sandwiched between each other, and a stress parallel to the y-axis direction is applied to the flexible member 210 at that position,
The flexible member 210 can be flexed. As each of the bending imparting means 241-244, for example, a solenoid, a direct drive motor, a screw, or the like is preferably used.

The optical waveguide type diffraction grating element 220 is one in which a Bragg grating is formed in an optical fiber that is an optical waveguide, and the light of a specific wavelength that has propagated through the optical fiber and is incident is Bragg-reflected by the Bragg grating, and The reflected light is propagated in the opposite direction to the incident direction. The optical waveguide type diffraction grating element 220 may have a uniform refractive index modulation grating interval along the longitudinal direction, or a chirp with a refractive index modulation grating interval varying along the longitudinal direction. It may be a Tobragg grating.

The optical waveguide type diffraction grating element 220 is fixed to the flexible member 210, and the bending imparting means 24 is provided.
Position C with respect to the neutral plane N1 when the flexible member 210 is deflected when stress is applied in the x-axis direction by
Is provided so as to cross diagonally (see FIG. 13).
(See (a)). Therefore, the bending imparting means 241 and 24
When the flexible member 210 is bent by the action of 2, the tensile stress acts on the optical waveguide type diffraction grating element 220 along the longitudinal direction on one side from the position C, and on the other side from the position C. Compressive stress acts along the longitudinal direction. That is, due to the action of the bending imparting means 241, 242, the optical component 200 according to the second embodiment operates in the same manner as the optical component 100 according to the first embodiment described above (see FIG. 5).

Further, this optical waveguide type diffraction grating element 220
Is provided parallel to the neutral plane N2 when the flexible member 210 is bent when stress is applied in the y-axis direction by the bending imparting means 243 and 244 (see FIG. 13B). ). Therefore, when the flexible member 210 is bent by the action of the bending imparting means 241, 242, uniform stress is applied to the optical waveguide type diffraction grating element 220 along the longitudinal direction.

The flexible member 210 may have a uniform cross-sectional area and rigidity along the longitudinal direction.
It is preferable that the cross-sectional area and / or the rigidity change along the longitudinal direction. By doing so, the distribution of the tensile stress or the compressive stress in the optical waveguide type diffraction grating element 220 when the flexible member 210 is bent can be made suitable.

The dispersion adjusting module including the optical component according to the second embodiment has substantially the same structure as the dispersion adjusting module 10 according to the first embodiment, and the optical component 100 is replaced with the optical component in FIG. 200 is provided. In addition, in the optical component 200 and the dispersion adjustment module according to the second embodiment, the flexure imparting means 241 and 24.
The operation when the flexible member 210 is flexed by the stress exerted in the x-axis direction by the action of 2 is similar to that shown in FIG. Below, the operation when the stress is applied in the y-axis direction by the action of the bending imparting means 243 and 244 will be mainly described.

FIG. 14 shows an optical component 20 according to the second embodiment.
It is a figure explaining operation | movement of 0. FIG. 11A shows the longitudinal distribution of strain in the optical waveguide type diffraction grating element 220. FIG. 6B shows the longitudinal distribution of the Bragg wavelength in the optical waveguide type diffraction grating element 220. In addition, FIG.
[Fig. 7] is a diagram for explaining the operation of the dispersion adjustment module according to the second embodiment. FIG. 6A shows the wavelength dependence of the light transmittance from the input end to the output end of the dispersion adjustment module.
FIG. 6B shows the wavelength dependence of the group delay time when light is transmitted from the input end to the output end of the dispersion adjustment module.

As shown in FIG. 14A, when the flexible member 210 is bent by the action of the bending imparting means 243 and 244, it is provided parallel to the neutral plane N2 at the time of bending. In the optical waveguide type diffraction grating element 220, uniform strain is generated along the longitudinal direction. As a result, in the optical waveguide type diffraction grating element 220, as shown in FIG.
The Bragg wavelength uniformly changes depending on the strain at each position. The strain and the Bragg wavelength in the optical waveguide type diffraction grating element 220 correspond to the bending direction and the bending degree of the flexible member 210. And FIG.
5, the transmission band, the transmittance, and the delay time of the light transmitted from the input end to the output end of the dispersion adjustment module change depending on the bending direction and the bending degree of the flexible member 210. .

That is, as shown in the comparison between the solid line and the broken line in FIG. 15 or the comparison between the one-dot chain line and the two-dot chain line, the action of the bending imparting hands 241 and 242 causes the optical waveguide type diffraction grating element 220. If the range of the Bragg wavelength along the longitudinal direction of is widened, the transmission band of the light transmitted from the input end to the output end of the dispersion adjustment module becomes wider, the transmittance in that band becomes smaller, and the wavelength of the group delay time becomes longer. The dependence will be loose. On the contrary, the bending imparting hands 241, 2
If the Bragg wavelength range along the longitudinal direction of the optical waveguide type diffraction grating element 220 is narrowed by the action of 42, the transmission band of the light transmitted from the input end to the output end of the dispersion adjusting module is narrowed, and the band is reduced. And the wavelength dependency of the group delay time becomes abrupt.

Further, as shown in the comparison between the solid line and the alternate long and short dash line in FIG. 15 or the comparison between the broken line and the alternate long and two short dashes line, the action of the bending imparting hands 243 and 244 causes the optical waveguide type diffraction grating element 220. If the Bragg wavelength along the longitudinal direction of the dispersion adjustment module becomes uniformly long, the transmission band of the light transmitted from the input end to the output end of the dispersion adjusting module shifts to the long wavelength side. On the contrary, if the Bragg wavelength along the longitudinal direction of the optical waveguide type diffraction grating element 220 is shortened uniformly by the action of the bending imparting hands 243 and 244, the light transmitted from the input end to the output end of the dispersion adjusting module is reduced. The transmission band shifts to the short wavelength side.

As described above, in the optical component 200 and the dispersion adjusting module according to the second embodiment, the flexible member 210 is simply bent so that the optical waveguide type diffraction grating element 220 intersects the neutral plane N1. Since the slope of the dispersion characteristic can be adjusted, and the wavelength band can be adjusted only by bending the flexible member 210 so that the optical waveguide type diffraction grating element 220 is parallel to the neutral plane N2. It is easy to adjust the dispersion characteristics.

(Modified Example of Optical Component) Next, a modified example of the optical component according to the present invention will be described. In the following, only the flexible member and the optical waveguide type diffraction grating element are shown, and description of the bending imparting means is omitted. Also, these optical components can be used as one component of the dispersion adjustment module as well.

FIG. 16 is a diagram illustrating a part of the configuration of the optical component 300 of the first modification. The flexible member 310 in the optical component 300 has a columnar shape and can bend in any direction. This flexible member 310
An optical waveguide type diffraction grating element 320 is embedded in the inside. The optical waveguide type diffraction grating element 320 is provided so as to obliquely intersect the neutral plane when the flexible member 310 is bent when stress is applied in the x-axis direction.
The optical waveguide type diffraction grating element 320 is provided parallel to the neutral plane when the flexible member 310 is bent when stress is applied in the y-axis direction.

Therefore, the optical component 300 and the dispersion adjusting module including the same operate as in the second embodiment when the flexible member 310 bends in the x-axis direction or the y-axis direction. In addition, since the flexible member 310 can bend in any direction, the optical component 300 and the dispersion adjusting module including the optical component 300 can be bent in a certain direction, and thus the slope and the band of the dispersion characteristic can be reduced. And can be adjusted at the same time.

The flexible member 310 preferably has a cross-sectional area and / or Young's modulus that change along the longitudinal direction. Alternatively, the flexible member 310
It is preferable that a truncated cone-shaped metal or the like having a high Young's modulus is embedded in the inside of the, and the outer shape of the truncated cone-shaped metal or the like is large on the fixed end side and small on the free end side. In any of these cases, the distribution of the tensile stress or the compressive stress in the optical waveguide type diffraction grating element 320 when the flexible member 310 bends can be made suitable.

FIG. 17 is a diagram for explaining a part of the configuration of the optical component 400 of the second modified example. The flexible member 410 of the optical component 400 has a columnar outer shape and can be bent in any direction. The flexible member 410 is formed by filling a low-Young's modulus resin 412 inside a high-Young's modulus substantially cylindrical pipe 411 whose inner diameter changes along the longitudinal direction.
An optical waveguide type diffraction grating element 420 is embedded in. The inner diameter of the pipe 411 is small on the fixed end side and large on the free end side. This optical waveguide type diffraction grating element 420 has x
It is provided so as to obliquely intersect the neutral plane when the flexible member 410 is bent when stress is applied in the axial direction. Further, the optical waveguide type diffraction grating element 420 is
It is provided parallel to the neutral plane when the flexible member 410 is bent when stress is applied in the y-axis direction.

Therefore, the optical component 400 and the dispersion adjusting module including the same also operate as in the case of the second embodiment by bending the flexible member 410 in the x-axis direction or the y-axis direction. In addition, since the flexible member 410 can bend in any direction, the optical component 400 and the dispersion adjusting module including the optical component 400 can be bent in a certain direction to allow the slope and band of the dispersion characteristic to be increased. And can be adjusted at the same time. In addition, since the inner diameter of the pipe 411 in the flexible member 410 changes along the longitudinal direction, the rigidity of the flexible member 410 changes along the longitudinal direction, and the optical component 400 has a desired dispersion. The characteristics can be obtained.

FIG. 18 is a diagram for explaining a part of the configuration of the optical component 500 of the third modified example. The flexible member 510 of the optical component 500 is a rectangular parallelepiped whose outer shape is long in the z-axis direction and can bend in any direction. The flexible member 510 has a uniform cross-sectional area along the longitudinal direction and a rigidity that varies along the longitudinal direction. The closer to the fixed end the rigidity is, and the closer to the free end the rigidity is. small. Specifically, the flexible member 510 includes a first member 511 having a large Young's modulus and a second member 5 having a medium Young's modulus.
12 and a third member 513 having a small Young's modulus. The first member 511 having a high Young's modulus has a larger cross-sectional area as it approaches the fixed end. The third member 513 having a low Young's modulus has a larger cross-sectional area as it approaches the free end. The second member 512 is sandwiched between the first member 511 and the third member 513, and the flexible member 51
As for 0, the cross-sectional area as a whole is uniform in the longitudinal direction.
The optical waveguide type diffraction grating element 520 is provided so as to obliquely intersect the neutral plane when the flexible member 510 is bent when stress is applied in the x-axis direction.
Therefore, the optical component 500 and the dispersion adjustment module including the same operate as in the first embodiment when the flexible member 510 bends in the x-axis direction. Further, the rigidity of the flexible member 510 changes along the longitudinal direction, so that the optical component 500 can obtain desired dispersion characteristics.

FIG. 19 is a diagram showing an example of strain distribution in the optical waveguide type diffraction grating element 520 of the optical component 500 of the third modification. Here, the flexible member 510 has a length of 60 mm in the z-axis direction and a thickness of 3 mm in the x-axis direction. The first member 511 is made of a material (for example, iron) having a Young's modulus of 20 × 10 ¹⁰ Pa, a length in the z-axis direction of 50 mm, a thickness in the x-axis direction at the fixed end position of 2 mm, and a thickness of z. It is assumed to change uniformly along the axis. The third member 513 is made of a material having a Young's modulus of 3 × 10 ¹⁰ Pa (for example, bismuth) and has a length in the z-axis direction of 30 m.
m and the thickness in the x-axis direction at the position of the free end is 1.5
mm, and the thickness thereof was assumed to change uniformly along the z axis. The second member 512 is made of a material having a Young's modulus of 7 × 10 ¹⁰ Pa (for example, aluminum). Further, the optical waveguide type diffraction grating element 520 is located at a position of 2 mm from the lower surface at the position of the fixed end and a distance of 50 m from the fixed end.
It is assumed that it intersects with the lower surface at the position of m. In the comparative example shown in the same figure, the entire flexible member has a Young's modulus of 20 × 1.
This is a case where the material is 0 ¹⁰ Pa. As shown in the figure, the entire flexible member has a Young's modulus of 20 × 10 ^10.
In the comparative example which is made of a material of Pa and has a uniform rigidity in the longitudinal direction, the strain distribution in the optical waveguide type diffraction grating element has a downward convex shape. On the other hand, in the modified example 3 in which the rigidity changes in the longitudinal direction with the above configuration, distortion in the optical waveguide type diffraction grating element 520 in the range from the position where the distance from the fixed end is 5 mm to the position where the distance is 35 mm. The distribution is linear with respect to the position in the z-axis direction. Thus, by appropriately setting the rigidity distribution in the longitudinal direction of the flexible member 510, the optical component 500 can obtain desired dispersion characteristics.

(Embodiment of Optical Communication System) Next, an embodiment of the optical communication system according to the present invention will be described.
FIG. 20 is a configuration diagram of the optical communication system 1 according to the present embodiment. An optical communication system 1 shown in this figure has an optical fiber transmission line 4 laid between an optical transmitter 2 and an optical receiver 3, and a dispersion adjustment module 10 is provided in the optical receiver 3. A reception unit 5, a measurement unit 6 and a control unit 7 are provided.

The optical transmitter 2 sends the signal light to the optical fiber transmission line 4. The optical receiver 3 receives the signal light propagated through the optical fiber transmission line 4. The dispersion adjustment module 10 provided in the optical receiver 3 compensates the chromatic dispersion of the optical fiber transmission line 4. The reception unit 5 includes the dispersion adjustment module 1
The signal light dispersion-compensated by 0 is received, and the signal light is converted into an electric signal. The measurement unit 6 measures the waveform distortion of the signal light output from the dispersion adjustment module 10 based on the electric signal output from the reception unit 5. The control unit 7 then, based on the measurement result by the measurement unit 6, the bending imparting means 141, 14 included in the dispersion adjustment module 10.
The amount of flexure of the flexible member 110 caused by 2 is controlled to adjust the dispersion characteristics of the optical waveguide type diffraction grating element 120 included in the dispersion adjustment module 10. By the feedback operation of the dispersion adjusting module 10, the receiving unit 5, the measuring unit 6, and the control unit 7 in the optical receiver 3, the dispersion characteristic of the dispersion adjusting module 10 compensates the chromatic dispersion of the optical fiber transmission line 4. Is adjusted.

The dispersion adjusting module 10 used in the optical communication system 1 is according to the above-described embodiment, and its dispersion characteristic can be adjusted. From this, the dispersion adjusting module 10 can be mass-produced with a certain standard, and after being installed in the optical receiver 3, the dispersion adjusting module 10 changes the dispersion characteristic according to the dispersion characteristic of the optical fiber transmission line 4 to be dispersion-compensated. Can be adjusted. Therefore, the dispersion adjustment module 10 can be manufactured at low cost, and
The optical communication system 1 also becomes inexpensive. Further, when the dispersion characteristic of the optical fiber transmission line 4 to be dispersion-compensated changes due to temperature change, the dispersion characteristic of the dispersion adjustment module 10 can be adjusted according to the change, so that the optical fiber transmission line is always The chromatic dispersion of No. 4 can be suitably compensated by the dispersion adjusting module 10.

When multi-wavelength signal light is multiplexed and transmitted from the optical transmitter 2 to the optical receiver 3, the arrived multi-wavelength signal light is demultiplexed in the optical receiver 3. After that, the chromatic dispersion is compensated by the dispersion adjusting module 10 for each wavelength.

The present invention is not limited to the above embodiment, but various modifications can be made. For example, instead of the optical component 100 included in the dispersion adjustment module 10 used in the optical communication system 1, the optical component 200 and the optical component 300 are used.
And the optical component 400.

[0068]

As described above in detail, according to the optical component of the present invention, when the flexible member is bent by the action of the first bending imparting means, the bending of the flexible member occurs. In the optical waveguide type diffraction grating element provided so as to intersect with the vertical surface, tensile stress acts along the longitudinal direction on one side from the intersection with the neutral surface to generate extension strain, and the intersection On the other side, compressive stress acts along the longitudinal direction to generate compressive strain. As a result, in the optical waveguide type diffraction grating element, the Bragg wavelength becomes longer depending on the degree of extensional strain at each position on one side of the intersection, and the Bragg wavelength becomes longer at each position on the other side of the intersection depending on the degree of compressive strain. The wavelength becomes shorter. The longitudinal distributions of the strain and the Bragg wavelength in the optical waveguide type diffraction grating element (the positive and negative of the inclination, the absolute value of the inclination) depend on the bending direction and the bending degree of the flexible member. The band, reflectance and dispersion characteristics of the light reflected by the waveguide type diffraction grating element change according to the bending direction and the bending degree of the flexible member. Further, the group delay characteristic of the dispersion adjusting module according to the present invention including this optical component also changes according to the bending direction and the bending degree of the flexible member. As described above, according to the present invention, the group delay characteristics can be easily adjusted only by bending the flexible member.

Further, the optical communication system according to the present invention includes the above-mentioned dispersion adjusting module according to the present invention, and the dispersion adjusting module compensates the chromatic dispersion of the optical fiber transmission line. According to this optical communication system, since the chromatic dispersion of the optical fiber transmission line is compensated by the dispersion adjusting module, high quality signal light transmission can be performed. Further, since the dispersion characteristic of the dispersion adjusting module can be adjusted, this dispersion adjusting module can be mass-produced with a certain standard, and after being installed, the dispersion of the optical fiber transmission line which is the object of dispersion compensation can be adjusted. The dispersion characteristics can be adjusted according to the characteristics. Therefore, the dispersion adjustment module can be manufactured at low cost, and the optical communication system can be manufactured at low cost.
Also, if the dispersion characteristics of the optical fiber transmission line subject to dispersion compensation fluctuate due to temperature changes, the dispersion characteristics of the dispersion adjustment module can be adjusted according to the fluctuations, so the wavelength of the optical fiber transmission line is always adjusted. The dispersion can be suitably compensated by the dispersion adjustment module.

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration of an optical component 100 according to a first embodiment.

FIG. 2 is an explanatory diagram of a method of fixing the optical waveguide type diffraction grating element 120 to the flexible member 110 in the optical component 100 according to the first embodiment.

FIG. 3 is an explanatory diagram of a method of fixing the optical waveguide type diffraction grating element 120 to the flexible member 110 in the optical component 100 according to the first embodiment.

FIG. 4 is a configuration diagram of a dispersion adjustment module 10 according to the first embodiment.

FIG. 5 is a diagram illustrating an operation example of the optical component 100 and the dispersion adjustment module 10 according to the first embodiment.

FIG. 6 is a diagram illustrating an operation example of the optical component 100 and the dispersion adjustment module 10 according to the first embodiment.

FIG. 7 is a flexible member 110 in the optical component 10 of the embodiment.
3A and 3B are diagrams illustrating a positional relationship between an optical waveguide type diffraction grating element 120.

8 is an optical waveguide type diffraction grating element 12 in the case of Example 1. FIG.
It is a figure which shows the longitudinal distribution of the strain in 0.

FIG. 9 is an optical waveguide type diffraction grating element 12 in the case of Example 2;
It is a figure which shows the longitudinal distribution of the strain in 0.

FIG. 10 is an optical waveguide type diffraction grating element 1 in the case of Example 3
It is a figure which shows the longitudinal distribution of the strain in 20.

FIG. 11 is an optical waveguide type diffraction grating element 12 in the case of a comparative example.
It is a figure which shows the longitudinal distribution of the strain in 0.

FIG. 12 is an optical waveguide type diffraction grating element 1 in the case of Example 3
It is a figure which shows the longitudinal distribution of the strain in 20.

FIG. 13 is a diagram showing a configuration of an optical component 200 according to a second embodiment.

FIG. 14 is a diagram illustrating the operation of the optical component 200 according to the second embodiment.

FIG. 15 is a diagram illustrating an operation of the dispersion adjustment module according to the second embodiment.

FIG. 16 is a diagram illustrating a part of the configuration of an optical component 300 of a first modified example.

FIG. 17 is a diagram illustrating a part of the configuration of an optical component 400 of a second modified example.

FIG. 18 is a diagram illustrating a part of the configuration of an optical component 500 according to a third modified example.

FIG. 19 is a diagram showing an example of strain distribution in an optical waveguide type diffraction grating element 520 of an optical component 500 of a third modified example.

FIG. 20 is a configuration diagram of an optical communication system 1 according to the present embodiment.

[Explanation of symbols]

1 ... Optical communication system, 2 ... Optical transmitter, 3 ... Optical receiver, 4
... optical fiber transmission path, 5 ... receiving section, 6 ... measuring section, 7 ... control section, 10 ... dispersion adjustment module, 100 ... optical component, 1
10 ... Flexible member, 120 ... Optical waveguide type diffraction grating element,
130 ... Fixing member, 141, 142 ... Bending imparting means, 1
90 ... Optical circulator, 200 ... Optical component, 210 ... Flexible member, 220 ... Optical waveguide type diffraction grating element, 230 ...
Fixing members, 241-244 ... Deflection imparting means.

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Toshikazu Shibata             Sumitomoden 1 Taya-cho, Sakae-ku, Yokohama-shi, Kanagawa             Ki Industry Co., Ltd. Yokohama Works F-term (reference) 2H038 AA24 BA25 BA27 CA52                 2H041 AA02 AB10 AC01 AZ02 AZ05                 2H050 AC84 AD01 BB01S BD06

Claims (11)

[Claims] 1. A flexible member having flexibility; a first bending imparting means for bending the flexible member by applying a stress to the flexible member in a first direction; (1) A Bragg grating is formed on an optical waveguide provided so as to obliquely intersect a neutral plane at the time of bending of the flexible member when a stress is applied by the bending applying means. An optical waveguide type diffraction grating element that Bragg-reflects light having a specific wavelength that has propagated through a waveguide and is incident by the Bragg grating, and propagates the reflected light in a direction opposite to that at the time of incidence. parts. 2. A second flexure imparting means for flexing the flexible member by applying stress to the flexible member in a second azimuth different from the first azimuth. The optical component according to claim 1. 3. The neutral plane at the time of bending of the flexible member when stress is applied by the second bending applying means, is parallel to the optical waveguide. Optical parts. 4. The optical component according to claim 1, wherein the flexible member is made of resin. 5. The flexible member is formed by molding the optical waveguide type diffraction grating element with resin.
The optical component according to claim 1, wherein: 6. The optical component according to claim 1, wherein the flexible member includes a first member and a second member that sandwich and fix the optical waveguide type diffraction grating element. 7. The optical component according to claim 1, wherein the flexible member has a long groove portion for fixing the optical waveguide type diffraction grating element. 8. The optical component according to claim 1, wherein the flexible member has a cross-sectional area and / or a rigidity that change along the longitudinal direction. 9. The method for adjusting an optical component according to claim 1, wherein the dispersion characteristic of the light reflected by the optical waveguide type diffraction grating element is monitored, and the first characteristic is monitored based on the monitoring result. An optical component adjusting method comprising adjusting the amount of bending of the flexible member by the bending applying means. 10. A dispersion comprising the optical component according to claim 1, wherein light is reflected by the waveguide type diffraction grating element included in the optical component to adjust wavelength dispersion of the light. Adjustment module. 11. An optical communication system for performing optical transmission using signal light, comprising the dispersion adjusting module according to claim 10, and compensating the chromatic dispersion of the optical fiber transmission line by the dispersion adjusting module. An optical communication system characterized by.