JP3369028B2 - Built-in structure of optical fiber and optical amplifier using this structure - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure for incorporating a long optical fiber and an optical amplifying device using this structure.

[0002]

2. Description of the Related Art FIG. 7 is a schematic configuration diagram of an optical amplifying device constructed by using an amplifying optical fiber.

In the figure, Lin is a signal light input connector, Lout is a signal light output connector, LD ₁ and LD ₂ are laser diodes as pumping light sources, and C ₁ and C ₂ mix signal light and pumping light. It is a multiplexer.

Further, I _{1 to} I ₃ are isolator DF ₁ , D for passing light in only one direction and preventing reflected light.
F ₂ is an amplification optical fiber that amplifies the signal light by the stimulated emission effect, and in this example, is formed by doping the rare earth element Er in the core or the outer periphery of the core. Further, F is an optical fiber for coupling each optical component or amplification optical fiber with each other.

The optical amplifying device shown in FIG. 7 has amplifying optical fibers DF ₁ and DF ₂ provided in a plurality of stages in order to obtain a large amplification factor. The amplification factor of ₁ and DF ₂ is determined by the density product of length (= density x length).

Therefore, each amplification optical fiber DF ₁ ,
In order to obtain the required amplification factor for each DF ₂ , the concentration can be adjusted by setting the concentration of the rare earth element such as Er or the strip length of the amplification optical fiber.

However, there is a natural limit to increasing the element concentration, such as deterioration of the characteristics of the optical fiber.
In this case, some length is required.

Further, when the optical parts are connected to each other through an optical fiber, an increase in bending loss of each optical fiber is avoided, and a reconnection margin for repairing a failure of the optical part is secured. Therefore, an extra length is required for each optical fiber as compared with the linear distance connecting each optical component.

In constructing the optical amplifying device shown in FIG. 7, various optical components such as the laser diode and the multiplexer described above are mounted on the substrate, and a long amplifying optical fiber and The optical fiber for coupling is installed in a wound state.

By the way, in order to wind the optical fiber compactly, a reel is usually used, but like the optical amplifying device shown in FIG. 7, there are a plurality of amplifying optical fibers and extra length portions. In this case, in the prior art, a reel is individually provided for each amplification optical fiber and an extra length portion, and the amplification optical fiber and the coupling optical fiber are wound around each reel, and then each reel is individually attached to the substrate. I am trying.

[0011]

However, when the amplification optical fibers and the reels around which the extra length portions are wound are separately mounted on the substrate as described above, the mounting area occupied for mounting the reels is large. Is large and the device cannot be sufficiently downsized.

The present invention has been made to solve the above problems, and an object of the present invention is to increase the packaging density by minimizing the occupied area when an optical fiber is incorporated in a device.

[0013]

The present invention adopts the following constitution in order to solve the above problems.

In the optical fiber assembling structure according to the first aspect of the present invention, a plurality of reels are provided, and each of these reels is externally fitted in order from the smallest diameter to the largest.
An optical fiber outlet is formed on a part of the peripheral wall of each reel except the innermost reel, the optical fiber is wound around each reel, and the light wound around a reel other than the outermost reel is formed. The fiber is pulled out of the reel through the optical fiber outlet.

According to a second aspect of the present invention, there is provided an optical fiber assembling structure, which comprises a single reel, and a flange portion of the reel is provided with an inlet and an outlet for the optical fiber penetrating inside and outside of the collar portion. And a plurality of optical fibers are wound around the barrel of the reel in layers through the inlets, and the lower optical fibers except the outermost optical fiber are pulled out of the reel through the outlets. There is.

[0016]

In the optical amplifying device according to the invention described in claim 3 , there is provided an optical fiber assembling structure according to claim 1 or 2, and the optical fiber wound around each reel constituting this assembling structure is: It is used as an optical fiber for amplification. Claim
In the optical amplifying device according to the invention described in claim 4,
In the optical amplifier, this optical amplifier is installed in each amplification stage.
The optical fibers for amplification are connected to each other.
It has a stage amplification configuration, and the amplifiers installed in each amplification stage
Each width optical fiber is wrapped around each reel
It has been burned.

[0018]

In the optical fiber built-in structure according to any one of claims 1 to 4 , since the extra length portions of the plurality of amplification optical fibers and the coupling optical fibers are arranged in one state by the reel, When the optical fiber is incorporated, the area occupied on the substrate becomes as small as possible , and the packaging density increases.

In particular, when the amplification optical fiber is wound around the reel to form the optical amplification device as described in claim 3 , the mounting area of the reel occupying the substrate becomes small, so that the entire device is miniaturized. Can be achieved. like this
The effect is, in particular, on each amplification stage as described in claim 4.
Multi-stage in which the provided optical fibers for optical amplification are connected to each other
The present invention is configured in an optical amplification device having an amplification configuration.
(That is, the amplification optical fiber provided in each amplification stage.
Each of the reels is wound around each of the reels)
Therefore, the advantage of claim 3 described above becomes remarkable.

[0020]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below by taking as an example the structure in which the amplifying optical fibers DF ₁ and DF ₂ constituting the optical amplifying device shown in FIG. 7 are incorporated.

Embodiment 1 FIG. 1 is an exploded perspective view of a reel used in an optical fiber assembling structure according to Embodiment 1 of the present invention, and FIG. 2 is a part of a state where the reel of FIG. 1 is mounted on a substrate. FIG.

In the built-in structure of the first embodiment, the inner reel 2
₁ and an outer reel 4 ₁ , both reels 2 ₁ and 4 ₁ are
For example, it is made of a synthetic resin such as transparent polycarbonate or other lightweight material, and both are annular body parts 2 ₁ a, 4 ₁ a and a pair of collar parts 2 ₁ b, 2 formed on both sides thereof.
Consisting of _{1 c, 4 1 b, 4} 1 c.

[0023] Then, the inner reel 2 _1, whereas (upper side in the drawing)
Than the outer diameter of the flange portion 2 ₁ b other are set as towards the outer diameter of the flange portion 2 ₁ c (lower side in the figure) increases. Further, fixing portions 2 ₁ d for screwing are formed at two locations on the inner peripheral surface of the body portion 2 ₁ a.

On the other hand, the outer reel 4 ₁ is set such that the inner diameter of its body portion 4 ₁ a is slightly larger than the outer diameter of one of the flange portions 2 ₁ b of the inner reel 2 _1. , Both collar parts 4
_{Both 1} b and 4 ₁ c have the same outer diameter and are set so as to match the outer diameter of the other flange portion 2 ₁ c of the inner reel 2 ₁ . Further, the outer reel 4 ₁ is formed with an optical fiber outlet 4 ₁ d.

The optical fiber outlet 4 ₁ d is, in this example,
The bottom surface of one of the flange portion 4 ₁ c in the radial direction is constituted by forming a groove. Although formation process of such a groove is easy, it is also possible to the optical fiber through the inside and outside of the flange portion 4 ₁ c to form a hole that can be inserted. The location where the optical fiber outlet 4 ₁ d is formed is not limited to the collar portions 4 ₁ b and 4 ₁ c, and may be formed in a part of the body portion 4 ₁ a as long as it does not hinder the winding of the optical fiber. Good.

As shown in FIG. 2, amplification optical fibers DF ₁ and DF ₂ are wound around the inner reel 2 ₁ and the outer reel 4 ₁ , respectively, and in particular, the optical fibers wound around the inner reel 2 _1. Both end portions of DF ₁ are drawn to the outside through the above-mentioned optical fiber drawing port 4 ₁ d. The end of the amplification optical fiber DF ₂ wound around the outer reel 4 ₁ is pulled out as it is.

Then, with the amplification optical fibers DF ₁ and DF ₂ wound around the reels 2 ₁ and 4 ₁ , the outer reel 4 ₁
Is fitted to the inner reel 2 ₁ , and further, in this state, the fixing portion 2 ₁ d of the inner reel 2 ₁ is screwed onto the substrate 8,
The reels 2 ₁ and 4 ₁ are mounted on the substrate 8.

In this configuration, since the plurality of amplification optical fibers DF ₁ and DF ₂ are arranged in one concentrated state by the reels 2 ₁ and 4 ₁ , these amplification optical fibers DF ₁ and DF ₂ are arranged. The area occupied on the substrate 8 in the case of incorporating is minimized and the mounting density is increased.

In particular, in the structure of the first embodiment, the entire built-in structure does not become bulky, and each amplification optical fiber DF is used.
_{Since 1} and DF ₂ are independently wound around the inner reel 2 ₁ and the outer reel 4 ₁ , respectively, the amplification optical fibers DF ₁ and D
F ₂ has the advantage that no extra lateral pressure is applied which causes bending losses.

In the first embodiment, two reels, the inner reel 2 ₁ and the outer reel 4 ₁ , are used. However, the number of reels is not limited to this, and many reels are sequentially fitted in multiple stages. It may be arranged.

Embodiment 2 FIG. 3 is a perspective view showing a reel used in an optical fiber assembling structure according to Embodiment 2 of the present invention, with a part of the reel cut away.
FIG. 5 is a cross-sectional view showing an enlarged introduction port of the optical fiber of the reel of FIG. 3, and FIG. 5 is a cross-sectional view showing a part of a state where the reel of FIG. 3 is mounted on a substrate.

The reel 2 ₂ used in the built-in structure of the second embodiment is made of a synthetic resin such as transparent polycarbonate or another lightweight material, and has an annular body ₂ 2a. A pair of collars 2 ₂ b, 2 ₂ c formed on both sides,
And a fixing portion 2 ₂ d for screwing, which is formed at two places on the inner peripheral surface of the body portion 2 ₂ a, is integrally molded.

In the present example, one (lower side in the drawing) of the collar portion ₂ 2c is
The two inlets 2 ₂ e, 2 ₂ f penetrate the inside and outside of this collar 2 ₂ c,
And one outlet 2 ₂ g are formed respectively.

Each of these inlets 2 ₂ e, 2 ₂ f and outlet 2 ₂ g
Is, in this example, as shown in FIG. 4, but is obtained by forming a through hole penetrating obliquely one of the flange portion 2 ₂ c over the inside and outside, outright across the flange portion 2 ₂ c inside and outside It can also be formed by a groove that is not provided. Further, the locations where the inlets 2 ₂ e, 2 ₂ f and the outlets 2 ₂ g are formed are not limited to the one flange portion 2 ₂ c, but are formed dispersedly on the left and right collar portions 2 ₂ b, 2 ₂ c. You may.

Of the above two inlets 2 ₂ e and 2 ₂ f, the amplification optical fiber DF ₁ passes through one inlet 2 ₂ e and the amplification optical fiber DF ₂ passes through the other inlet 1 ₂ f. Each is wound around the body 2 ₂ a of the reel 2 ₂ . Therefore, as shown in FIG. 5, both amplification optical fibers DF ₁ and D
F ₂ is wound around reel 2 ₂ in two layers.

The amplification optical fiber D on the lower layer side
F ₁ is pulled out of the reel 2 ₂ through one outlet 2 ₂ g. In addition, the amplification optical fiber DF ₂ on the upper layer side
Are drawn to the outside as they are.

[0037] Thus, the closest position inlet 2 ₂ e of the amplification optical fiber DF ₁ as the inner layer side to the body portion 2 ₂ a, also, the inner layer-side amplifying optical fiber DF ₁ of outlet 2 ₂
f and the outlet 2 ₂ g of the amplification optical fiber DF ₂ on the outer layer side are
The amplification optical fiber DF ₁ on the inner layer side is formed at a position that is separated from the body 2 ₂ a by substantially the same distance in the radial direction according to the thickness of the winding layer.

Then, by fixing the fixing portion 2 ₂ d onto the substrate 8 with the amplification optical fibers DF ₁ and DF ₂ wound around the reel 2 ₂ in two layers, the reel 2 ₂ becomes the substrate. 8 is mounted on.

In this structure, as in the first embodiment,
Since a plurality of the amplification optical fiber DF _1, DF ₂ is arranged in a state of being concentrated on one place by the reel 2 _2, when incorporating these amplification optical fiber DF _1, DF ₂ substrate 8
The area occupied on the top is as small as possible, and the mounting density is increased.

Particularly, in the structure of the second embodiment, since the single reel 2 ₂ is used, the structure is simple, and moreover,
It has the advantage of not becoming bulky.

In the second embodiment, the amplification optical fibers DF ₁ and DF ₂ wound around the reel 2 ₂ have two layers, but the number is not limited to this, and the amplification optical fibers may be spread over multiple layers. A wound configuration is also possible.

Embodiment 3 FIG. 6 is a sectional view showing a state in which a reel used in an optical fiber assembling structure according to Embodiment 3 of the present invention is mounted on a substrate.

The built-in structure of the third embodiment is such that the lower reel 2 ₃
And the upper reel 4 ₃ , both reels 2 ₃ and 4 ₃ are
For example, it is made of a synthetic resin such as transparent polycarbonate or other lightweight material, and both of them are annular body portions 2 ₃ a, 4 ₃ a and a pair of collar portions 2 ₃ b, 2 formed on both sides thereof.
₃ and a _{c, 4 3 b, 4 3} c.

Both reels 2 ₃ and 4 ₃ have substantially the same shape, and in particular, fixing portions 2 ₃ d for screwing are provided at two locations on the inner peripheral surface of the body portion 1 ₃ a of the lower reel 2 _3. Is provided.

Amplification optical fibers DF ₁ and DF ₂ are wound around the reels 2 ₃ and 4 ₃ , respectively,
This state is the upper reel 4 ₃ on the lower reel 2 ₃ stacked secured, further, by screwing the fixing portion 2 ₃ d of lower reel 2 ₃ on the substrate 8 in this state, the reel 1 ₃ substrate 8 is mounted on.

In this structure, as in the first and second embodiments, since the plurality of amplification optical fibers DF ₁ and DF ₂ are arranged in one concentrated state by the upper and lower reels 2 ₃ and 4 ₃ , When these amplification optical fibers DF ₁ and DF ₂ are incorporated, the area occupied on the substrate 8 is minimized and the mounting density is increased.

Particularly, in the configuration of the third embodiment, the first embodiment
Similarly to the amplification optical fibers DF ₁ and DF _2, the lower reel 2
_{Since 3} and the upper reel 4 ₃ are independently wound, there is an advantage that extra lateral pressure that causes bending loss is not applied to each of the amplification optical fibers DF ₁ and DF ₂ .

In the third embodiment, the lower reel 2 ₃ and the upper reel 4 ₃ are laminated in two stages. However, the present invention is not limited to this, and many reels are sequentially laminated in multiple stages. It can also be configured.

In each of the first to third embodiments described above, the built-in structure of the amplification optical fibers DF ₁ and DF ₂ has been described as an example.
The present invention is not limited to this, and the present invention can be applied to the case of a built-in structure for processing the extra length of the optical fibers F ₁ , F _2, etc. And for this extra length processing,
Even when this built-in structure is used, there is an effect that the mounting area can be reduced.

Further, when the optical amplifying device is constructed by using the built-in structure of the first to third embodiments, the mounting area of the built-in structure of the optical fiber on the substrate 8 becomes small, so that the whole device is small. Can be realized.

[0051]

According to the present invention, the following effects can be obtained.

(1) In the optical fiber built-in structure according to the first to fourth aspects of the invention, the apparatus is provided in a state where the extra length portions of the amplification optical fiber and the coupling optical fiber are concentrated in one place by the reel. because incorporated into, become small fence as possible the area occupied on the substrate of the reel, it increased packing density.

(2) In the optical amplifying device according to the invention as defined in claim 3, even when there are a plurality of amplifying optical fibers, these can be compactly housed in the case, so that they are occupied for mounting the amplifying optical fibers. The area is reduced, and the overall size of the device can be reduced. Such an effect is
According to claim 4, each amplification stage is provided with
A multi-stage amplification configuration in which optical fibers for optical amplification are connected to each other
Remarkable when the present invention is implemented in an optical amplifier having
It can be obtained as

[Brief description of drawings]

FIG. 1 is an exploded perspective view of a reel used in an optical fiber assembling structure according to a first embodiment of the present invention.

2 is a sectional view showing a part of a state where the reel of FIG. 1 is mounted on a substrate.

FIG. 3 is a perspective view showing a reel used in an optical fiber assembling structure according to a second embodiment of the present invention with a part thereof cut away.

FIG. 4 is an enlarged cross-sectional view showing an introduction port of an optical fiber of the reel of FIG.

5 is a sectional view showing a part of a state where the reel of FIG. 3 is mounted on a substrate.

FIG. 6 is a cross-sectional view showing a state where a reel used in an optical fiber assembling structure according to a third embodiment of the present invention is mounted on a substrate.

FIG. 7 is an overall configuration diagram of optical amplification attachment.

[Explanation of symbols]

2 ₁ , 2 ₂ , 2 ₃ , 4 ₁ , 4 ₃ ... reel 2 ₁ a, 4 ₁ a, 2
_{2 a, 2 3 a, 4} 3 a ... _{barrel, 2 1 b, 2 1 c} , 4 1 b, 4 1 c, 2
_{2 b, 2 2 c, 2} 3 b, 2 3 c, 4 3 b, 4 3 c ... flange portion, 4 ₁ d ... optical fiber _{outlets, 2 2 e, 2 2 f} ... inlet, 2 ₂ g ... Outlet, D
F ₁ , DF _2, ... Optical fiber for amplification, F ₀ , F ₁ , F _2, etc.
Optical fiber for coupling, LD ₁ , LD ₂ ... Laser diode,
C _1, C ₂ ... _{multiplexer, I 1, I 2, I} 3 ... isolator.

─────────────────────────────────────────────────── ─── Continuation of the front page (56) Reference JP-A-5-313036 (JP, A) Actually open 63-24503 (JP, U) Actually open 6-8906 (JP, U) Actually open 4- 49164 (JP, U) Actual Kaihei 7-159626 (JP, U) (58) Fields investigated (Int.Cl. ⁷ , DB name) G02B 6/00 G02B 6/24 G02B 6/36-6/40

Claims (4)

(57) [Claims] 1. A plurality of reels are provided, and each of these reels is externally fitted in order from the smallest diameter to the largest, and an optical fiber outlet is formed on a part of the peripheral wall of each reel except the innermost reel. An optical fiber is wound around each of the reels, and the optical fiber wound around a reel other than the outermost reel is drawn out of the reel through the optical fiber outlet. Optical fiber built-in structure. 2. A single reel is provided, and an inlet and an outlet for an optical fiber penetrating the inside and outside of the collar are respectively formed in the collar of the reel, and the reel body is passed through the inlets. A plurality of optical fibers are wound in layers on the optical fiber, and an optical fiber on the lower layer side excluding the optical fiber of the outermost layer is pulled out to the outside of the reel through the outlet. 3. The optical fiber according to claim 1 or 2.
It has a built-in structure and is wound around each reel that constitutes this built-in structure.
The optical amplifying device characterized in that the optical fiber to be attached is an amplifying optical fiber . 4. The optical amplifying device according to claim 3, wherein the optical amplifying device is provided for each of the amplifying stages.
It has a multistage amplification configuration in which optical fibers are connected to each other.
The amplification optical fibers provided in each amplification stage.
An optical amplifying device, which is wound around each of the reels .