JP2003215354A - Optical module and optical distributing frame - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To facilitate the replacing work of optical distribution by easily performing excess length treatment of optical fibers. <P>SOLUTION: An optical module 12 is provided with a module side optical fiber which has an excess part 31a bent and stored in a module body 13 and a coated optical fiber 33A which is led into the module body 13 and has one end connected to the other end of the module side optical fiber 31 and has an excess part 33a bent and stored in the module body 13, and the rear end of the module body 13 is opened, and a hook part 18 is provided on the inside surface side of the module body 13 adjacent to the rear end opening. After the module side optical fiber 31 and the coated optical fiber 33A are connected, the excess part 33a of the coated optical fiber 33A is bent on the outside of the module body 13 and is put on the hook part 18. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical module and an optical wiring board, and more particularly to an optical module in which optical wiring can be easily replaced and an optical wiring board equipped with the optical module.

[0002]

2. Description of the Related Art There are various types of optical wiring boards, for example, those shown in FIGS. 19 to 27 are known. FIG. 19 is a front view of the optical wiring board, and FIG. 20 is a rear view thereof. As shown in these drawings, the optical wiring board 51 includes a frame 52 and an external optical fiber wiring provided on the right side of the frame 52. A first optical wiring board 55 used for the above, a second optical wiring board 56 used for intra-site optical fiber wiring provided on the left side of the frame 51, a first optical wiring board 55 and a second optical wiring board 56. And a switching optical fiber wiring part 57 provided between the two.

The first optical distribution board 55 comprises a plurality of optical modules 62 arranged side by side in a lateral direction to form a termination unit 61 (optical module group). It is configured by fixing stages.

In the second optical wiring board 56, a plurality of optical connector adapters 71 are fixed to the panel 41 and a connection unit 70 is provided.
(Optical connector adapter group), and the connection units 70 are fixed to the frame 52 through the panel 41 in a plurality of stages.

As shown in FIG. 20, a plurality of first optical fiber cables 83, for example, external optical fiber cables, are guided to the first optical distribution board 55 from above in the vertical direction. The optical fiber core wire 83A is pulled out, the optical fiber core wire 83A is bent in the horizontal direction on the back surface side of the frame 51, and along the horizontal frame 53 of the frame 51, to the switching optical fiber wiring part 57 at the center of the frame 52. It is guided to the front side of the frame 52 from there, and as shown in FIG. 21 and FIG. 22, is guided to the wiring duct 58A provided at the upper portion of each termination unit 61, and from the wiring duct 58A. Each optical module 62 is guided to the front side of each optical module 62 of the termination unit 61.
Is guided to the inside of each optical module 62 from the front side.

Each optical module 62 has a box-shaped module main body 63, and an optical connector adapter 69 is provided on the front side of the module main body 63. The optical connector adapter 69 has a plurality of internal and external modules. The optical connector plug is removable. An opening portion 63a penetrating the inside and outside of the module body 63 is provided in the upper portion of the optical connector adapter 69 on the front side of the module body 63, and the optical fiber core wire 83A is provided through this opening portion 63a.
Are drawn into the module body 63.

As shown in FIG. 22, the module main body 63 accommodates a surplus length treating portion 81a of the module side optical fiber core wire 81 which is curved, and one end of the module side optical fiber core wire 81 is It is connected to the optical connector adapter 69 via the optical connector plug 82. Further, the other end of the module-side optical fiber cable 81 is fusion-spliced with the tip of an optical fiber core wire 83A guided inside the module main body 63, and the fusion-spliced connecting portion 84 and the optical fiber core are connected. The surplus length processing portion 83a of the curved line 83A is also housed in the module main body 63.

25 to 27 show the details of the module main body 63. As shown in these drawings, the module main body 63 is formed in a thin plate box shape, and includes a top wall 91, a bottom wall 92, a front wall 93, a rear wall 94, and left and right side walls 95, 96. It is formed in a box shape, and a partition plate 97 is provided inside thereof. This module body 6
3, the side walls 95 and 96 are openable and closable, and the module side optical fiber core wire connected to the optical connector adapter 69 provided on the front wall 93 in one space 98 partitioned by the partition wall 97. 81 extra length processing unit 81a is arranged,
In the other space 99, the connection portion 84 and the surplus length processing portion 83a of the optical fiber core wire 83A are arranged.

As shown in FIGS. 21 and 22, the optical connector adapter 6 of each optical module 62 of each termination unit 61.
On the front side of the optical fiber cable 9, one end of a switching optical fiber cable 86 (also referred to as a jumper cord) has an optical connector plug 82.
Connected through.

The switching optical fiber cable 86 is provided in the wiring duct 5 provided under each termination unit 61.
8B, from the wiring duct 58B, as shown in FIG. 19, the switching optical fiber wiring portion 57 in the central portion of the frame 52.
To the second optical wiring board 56 from that portion, and is guided to the wiring duct 42A shown in FIGS. 23 and 24 provided below the connection units 70 of the second optical wiring board 56, and wiring is performed. It is guided from the duct 42A to the front side of the optical connector adapter 71 fixed to the panel 41, and is connected to the front side of each optical connector adapter 71 via an optical connector plug 82.

As shown in FIG. 20, a plurality of second optical fiber cables 89, for example, intra-station optical fiber cables, are guided to the second optical distribution board 56 from above in the vertical direction, and optical signals are transmitted from the second optical fiber cables 89. Fiber cord 89A
And the optical fiber cord 89A is bent in the horizontal direction on the back side of the frame 52,
2 is guided to the switching optical fiber wiring portion 57 at the center of the frame 52 along the horizontal frame 53, and from that portion to the wiring duct 42B provided at the bottom of each connection unit 70 shown in FIG. Each optical connector adapter 7 is guided from the duct 42B to the back side of each optical connector adapter 71.
The optical connector plug 82 is connected to the back side of the No. 1 unit.

[0012]

By the way, in the optical wiring board 51 having the above-described structure, when the optical wiring is replaced on the side of the first optical wiring board 55, the optical module 62 is framed. The optical module 62 is taken out from the front of the frame 52, the optical module 62 is installed on the workbench installed in front of the frame 52, and the work is performed in this state. Therefore, at the time of this work, an extra length for pulling out each optical module 62 to the workbench is particularly required for the first optical fiber core wire 83A. For this reason, the optical module 62 needs an extra length for drawing out, which requires a long extra length. Therefore, the module body 63 needs to have a thickness capable of accommodating the extra length, the width of the module body 63 becomes wide, and the switching optical fiber wiring part 57 between the first optical wiring board 55 and the second optical wiring board 56 is required. However, there was a problem that the work space became narrow and the work efficiency became very poor.

Further, the optical module 62 is installed on the workbench, and in this state, the inside of the module main body 63 is opened to perform the optical wiring replacement work, and after the work is completed, the remainder of the first optical fiber core wire 83A is left. Since the long processing portion 83a is housed inside the module body 63, then the open part of the module body 63 is closed, and the optical module 62 is housed in the support body 54, the replacement work of the optical wiring is very troublesome. There is also a problem in that work efficiency is extremely deteriorated from this point as well.

The present invention has been made in view of the conventional problems as described above, and when the optical wiring is replaced in the first optical wiring board, the extra length of each optical fiber is exclusively used for drawing. The width of the module body of each optical module for accommodating the extra length can be reduced, and the switching light between the first optical wiring board and the second optical wiring board can be reduced. The width of the fiber wiring part can be widened, and the work space can be widened, which can greatly improve the efficiency of the replacement work of the optical wiring, and the optical fiber cable of each optical module. It is an object of the present invention to provide an optical module and an optical wiring board which can easily perform extra length processing and can significantly improve the efficiency of optical wiring replacement work.

[0015]

In order to achieve the above object, the present invention employs the following means. That is, in the invention according to claim 1, an optical connector adapter is provided at a front end portion of a thin plate box-shaped module main body, and a module-side optical connector connected to the optical connector adapter via an optical connector plug is provided in the module main body. A fiber and a first drawn externally into the module body
Optical fiber, the module side optical fiber and the first
In an optical module in which a connection portion with an optical fiber and a surplus length processing portion of the first optical fiber are arranged, a rear end portion of the module body is opened, and the surplus length is provided inside the rear end opening portion. It is characterized in that a hooking portion for hooking the processing portion is provided.

According to the optical module of the present invention, the surplus length of the first optical fiber is curved outside the module body, and the curved surplus portion is hooked from the rear end opening to the hooking portion. Will be

According to a second aspect of the present invention, in the optical module according to the first aspect, the portion of the hooking portion facing the front end side of the module body is an inclined surface.

According to the optical module of the present invention, when the extra length hooked on the hooking portion is removed, the inclined surface prevents the extra length from being caught by the hooking portion.

The invention according to claim 3 is characterized in that a plurality of the optical modules according to claim 1 or 2 are mounted.

According to the optical distribution board of the present invention, in each optical module, the surplus length of the first optical fiber is curved outside the module body, and the curved surplus portion is hung from the rear end opening. It will be hooked on the stop.

[0021]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention shown in the drawings will be described below. 1 to 3 show an embodiment of an optical distribution board according to the present invention. FIG. 1 is a front view showing the whole, FIG. 2 is a rear view showing the whole, and FIG.
FIG. The optical distribution board 1 shown in these figures is
A frame 2 and a first optical wiring board 5 used for external optical fiber wiring provided on the right side of the frame 2,
A second optical wiring board 6 used for intra-station optical fiber wiring provided on the left side of the frame 2 and a first optical wiring board 5
And a switching optical fiber wiring section 7 provided between the optical fiber wiring board 6 and the second optical wiring board 6.

The first optical wiring board 5 constitutes a termination unit 11 (optical module group) by arranging a plurality of optical modules 12 according to an embodiment of the present invention in the lateral direction, and the termination unit 11 is supported by the support 4 The optical module 12 of each terminating unit 11 is attachable to and detachable from the back side of the frame 2 with respect to the support body 4.

In the second optical wiring board 6, a plurality of optical connector adapters 21 are fixed to the panel 41 to form a connection unit 20 (optical connector adapter group).
A plurality of stages are fixed to the frame 2 via the panel 41, and this configuration is shown in FIGS.
Is the same as that shown in.

A plurality of first optical fiber cables 33, for example, external optical fiber cables are drawn into the first optical distribution board 5 from above in the vertical direction, and the optical fiber core wires 33A (first optical fiber cables 33) 1 optical fiber) is drawn out, and the optical fiber core wire 33A is guided to the wiring duct 8 provided in the lower portion of each termination unit 11 along the horizontal frame 3 of the frame 2 on the back surface side of the frame 2.
The wiring duct 8 leads to the rear surface side of each optical module 12, and the rear surface side of each optical module 12 leads to the inside of each optical module 12.

As shown in FIGS. 4 to 9, each optical module 12 has an external thin plate box-shaped module main body 13 having an open rear end, and an optical connector adapter is provided on a front wall 13 a of the module main body 13. 19 is provided, and a plurality of optical connector plugs can be attached to and detached from the front side and the back side of the optical connector adapter 19.

As shown in FIGS. 5, 6 and 8, a partition plate 13d is provided inside the module main body 13, and the partition plate 13d allows the inside of the module main body 13 to extend from the center to the front end side. Two storage chambers 14 in part,
It is divided into 15. Further, as shown in FIG. 8, the rear end portion of the partition plate 13d is bent at the bending position 13e and positioned closer to the side wall 13b, so that the storage chamber 16 is formed at the rear end portion of the module body 13. Has been done.

That is, the front side of the central portion of the module main body 13 is divided into the first storage chamber 14 and the second storage chamber 15 in the width direction by the partition plate 13d, and the first storage chamber 14 and the second storage chamber 15 are arranged in the rear side of the central portion. The third storage chamber 16 is formed, and the third storage chamber 16 is formed.
The rear end portion is opened to form a rear end opening portion 16A.
In this case, both side walls 13b and 13c of the module body 13
Also serves as a lid that can be freely opened and closed. These lids 13b and 13c
The side portions of the storage chambers 14, 15 and 16 can be opened by removing.

As shown in FIG. 6, the module side optical fiber 31 is accommodated in the first accommodating chamber 14 of the module body 13 with the extra length 31a being curved. The optical connector plug 3 is provided at one end of the module side optical fiber 31.
2 is mounted, and one end of the module side optical fiber 31 is connected to the optical connector adapter 1 through the optical connector plug 32.
9 is connected to the back side. As shown in FIG. 5, the other end of the module side optical fiber 31 has a second storage chamber 15 through a through hole (not shown) provided in the partition plate 13d.
It is drawn to the side and is curved in the second storage chamber 15 to form an extra length processing portion 31a.

As shown in FIG. 6, an optical fiber core wire 33A is drawn into the third storage chamber 16 of the module main body 13 from the rear end opening 16A, and the optical fiber core wire 3 is drawn.
3A is drawn into the second storage chamber 15 shown in FIG. 5 after forming an extra length processing portion 33a whose details will be described later,
The tip of the second storage chamber 15 is fusion-spliced to the other end of the module-side optical fiber 31. Optical fiber core 3
Fusion splicing portion 34 between 3A and module-side optical fiber 31
A sleeve 35 is fitted to the (connection portion), and in this state, the sleeve 35 is held by the holder 17 provided on the partition plate 13d. The surplus length processing portion 33a of the optical fiber core wire 33A, which has been subjected to the bending treatment, is hooked on the hooking portion 18 in a wound state.

As shown in FIGS. 6 to 9, the inner surface of the lid 13b, which also serves as one side wall 13b of the module body 13, is
A cylindrical hooking portion 18 is integrally provided, and this hooking portion 18
The surplus length processing portion 33a of the optical fiber core wire 33A is hooked on. In this case, the portion of the hooking portion 18 facing the front side of the module main body 13 is chamfered to form an inclined surface 18a having a predetermined angle, and the inclined surface 18a bends the optical fiber core 33A from the hooking portion 18. The extra length processing unit 33a that has been processed is made easy to remove.

As shown in FIGS. 10 to 12, the optical connector adapter 1 of each optical module 12 of each termination unit 11 is shown.
One end of a switching optical fiber 36 having optical connector plugs 32, 32 attached to both ends is connected to the front side of the optical fiber 9 through the optical connector plug 32.

The switching optical fiber 36 is guided to the wiring duct 8 provided under each terminating unit 11, and the frame 2 shown in FIGS.
It is guided to the switching optical fiber wiring portion 7 in the central portion, guided from that portion to the second optical wiring board 6, and guided to the wiring duct 8 provided under each connection unit 20 of the second optical wiring board 6. Then, it is guided from the wiring duct 8 to the front side of each optical connector adapter 21, and the other end is connected to the front side of each optical connector adapter 21 via an optical connector plug.

In the first optical wiring board 5 of the optical wiring board 1 having the above structure, for example, in order to replace the optical wiring, first, the optical module 12 is removed from the support 4 as shown in FIG. , Is attached to the workbench 40. next,
As shown in FIG. 14, remove the lid 13c (13b),
The inside of the second storage chamber 15 of the module main body 13 is opened, and the module side optical fiber 31 is released from the inside of the second storage chamber 15.
And the fusion splicing portion 34 of the optical fiber core wire 33A is pulled out, and the fusion splicing portion 34 is cut.

Next, as shown in FIGS. 15 and 16, another module side optical fiber 31 and an optical fiber core wire 33A are provided.
And are fusion-spliced, and the fusion-spliced portion 34 is held by the holder 17 of the partition plate 13d. In this case, the surplus length 31a generated in the module side optical fiber 31 is curved and stored in the second storage chamber 15.

Next, as shown in FIG. 17, the lid 13c (1
3b) is attached to the module body 13 and the module body 13 is returned into the support body 4. Next, as shown in FIG. 18, the surplus length generated in the optical fiber core wire 33A behind the module main body 13 is curved, and the surplus length processing portion 33a subjected to the curving processing is provided from the rear end opening 16A to the third end. It is guided into the storage chamber 16 and is hooked by the hooking portion 18 provided on the inner surface of the lid 13b.

By performing such an optical wiring replacement operation for each optical module 12, the optical wiring replacement operation can be performed for all the optical modules 12 of the first optical wiring board 5.

In the optical wiring board 1 according to this embodiment configured as described above, when the optical wiring is replaced on the side of the first optical wiring board 5, each optical module 13 is replaced.
After removing the extra length of the optical fiber core wire 33A from the rear end opening 16A, each optical module 12 is taken out rearward from the frame 2 and mounted on the workbench 40, and the inside of each optical module 12 is opened in this state. Since the work such as the fusion splicing process is performed by doing so, the extra length of the optical fiber core wire 33A can be made shorter than the conventional one.

Further, the second storage chamber 15 for accommodating the fusion splicing portion 34 between the module side optical fiber 31 and the optical fiber core wire 33A and the surplus length processing portion 33a for the curved processing of the optical fiber core wire 33A are accommodated. Since the third storage chamber 16 is partitioned and provided in the longitudinal direction of the module main body 13, the extra length of the optical fiber core wire 33A is short,
The width of the module body 13 can be made smaller than that of the conventional one. Further, the extra length 33a of the optical fiber core wire 33A allows the work to be performed without opening the inside of each optical module 12, and thus the work is facilitated.

According to the optical module 12 and the optical wiring board 1 described above, the first optical wiring board 5 on which the optical module 12 is mounted is installed.
Then, the space of the switching optical fiber wiring portion 7 between the second optical wiring board 6 and the second optical wiring board 6 can be expanded. Therefore, the space for the replacement work of the optical wiring can be widened, so that the working efficiency can be greatly improved.

When the optical wiring is replaced,
Due to the inclined surface 18a of the hook portion 18, the optical fiber core wire 33A
Since it is possible to prevent the extra length processing section 33a of the optical device from being caught by the hooking section 18, the extra length processing section 33a hooked on the hooking section 18 can be easily formed without opening the module body 13 of the optical module 12. And it can be taken out surely. Therefore, the replacement work of the optical wiring becomes easy, and the working efficiency can be greatly improved.

Further, since the hooking portion 18 is provided in the portion adjacent to the rear end opening 16A of the module body 13, the hooking portion 18 is fused to the module side optical fiber 31 and the optical fiber core wire 33A. Since the connection part can be separated from the place where it is stored, the entire optical module 12 can be made horizontally long.

Further, since the wiring duct is not required above the optical module 12, the storage position of the optical module 12 can be shifted upward by the amount of the wiring duct. Therefore, a larger work space for handling the switching optical fiber cable and the like can be secured, and work efficiency can be significantly improved.

[0043]

As described above, the optical module and the optical wiring board according to the present invention have the following effects. (1) Since the width of the optical module can be reduced,
This makes it possible to increase the space of the switching optical fiber wiring section between the first optical wiring board on which the optical module is mounted and the second optical wiring board. Therefore, the space for the replacement work of the optical wiring can be widened, so that the working efficiency can be greatly improved.

(2) When the optical wiring is replaced,
The extra length of the first optical fiber is taken out from the hooking portion of the optical module, the optical module is removed from the frame in this state, and the module body of the optical module is opened on the workbench to perform the fusion splicing work and the like. . Therefore, there is no need to secure an extra length (so-called extra length) for removing the optical module from the frame and pulling it out to the workbench, as the extra length of the first optical fiber hooked on the hook portion.
The extra length of the optical fiber can be shortened, and the extra length processing can be facilitated.

(3) When replacing optical fiber,
The slanted surface of the hooking portion can prevent the extra length of the first optical fiber from being caught in the hooking portion. Therefore, even if the module body of the optical module is not opened, the extra length of the hooking portion can be reduced. It can be taken out easily and surely.
Therefore, the replacement work of the optical wiring becomes easy, and the working efficiency can be greatly improved.

(4) Since the hooking portion is provided in the portion adjacent to the rear end opening of the module body, the hooking portion accommodates the fusion splicing portion between the module side optical fiber and the first optical fiber. Since it can be separated from the place, the entire optical module can be made horizontally long. Therefore, since the optical module can be made thin, the space for the switching optical fiber cable wiring portion between the first optical wiring portion and the second optical wiring portion can be widened, and the space for the replacement work of the optical wiring can be widened. Therefore, the working efficiency can be significantly improved.

[Brief description of drawings]

FIG. 1 is a front view of an optical distribution board shown as an embodiment of the present invention.

FIG. 2 is a rear view of the optical distribution board shown as an embodiment of the present invention.

3 is a cross-sectional view taken along the line AA of FIG.

FIG. 4 is a front view of an optical module shown as an embodiment of the present invention.

FIG. 5 is a right side view of the optical module shown as the embodiment of the present invention in a state where the inside is opened.

FIG. 6 is a left side view of the optical module shown as the embodiment of the present invention in a state where the inside is opened.

FIG. 7 is a side view of the optical module shown as an embodiment of the present invention in a state of seeing through a hooking portion.

FIG. 8 is a top view of an optical module shown as an embodiment of the present invention.

FIG. 9 is a rear view of the optical module shown as the embodiment of the present invention.

FIG. 10 is a front view of the termination unit of the optical distribution board shown as an embodiment of the present invention.

FIG. 11 is a right side view of the termination unit of the optical distribution board shown as the embodiment of the present invention.

FIG. 12 is a plan view of a termination unit of an optical wiring board shown as an embodiment of the present invention.

FIG. 13 is an explanatory diagram showing the procedure of the optical wiring replacement work, showing the procedure of pulling out the optical module from the panel and mounting it on the workbench.

FIG. 14 is an explanatory view showing a procedure of a work of exchanging optical wiring, wherein the lid is opened to open the insides of the second storage chamber and the third storage chamber, and the module-side optical fiber and the first optical fiber are separated. It is explanatory drawing which showed the procedure of pulling out a fusion splicing part and cutting | disconnecting the fusion splicing part.

FIG. 15 is an explanatory view showing the procedure of the optical wiring replacement work, in which the first optical fiber is replaced and fusion-spliced to another module-side optical fiber, and the fusion-spliced portion is held in a holder. It is explanatory drawing which showed the procedure.

FIG. 16 is an explanatory view showing a procedure of a work of replacing the optical wiring, and showing a procedure of bending and storing the extra length of the module side optical fiber.

FIG. 17 is an explanatory view showing the procedure of the optical wiring replacement work, showing the procedure of pulling out the extra length of the first optical fiber, closing the lid, and returning the optical module into the panel.

FIG. 18 is an explanatory diagram showing a procedure of a work of replacing the optical wiring, showing a procedure of bending the surplus length of the first optical fiber and hooking the curbed surplus length on the hook portion. FIG.

FIG. 19 is a front view of a conventional optical distribution board.

FIG. 20 is a rear view of a conventional optical distribution board.

FIG. 21 is a front view of a termination unit of a conventional optical distribution board.

FIG. 22 is a side view of a termination unit of a conventional optical distribution board.

FIG. 23 is a front view of a connection unit of a conventional optical distribution board.

FIG. 24 is a side view of a connection unit of a conventional optical distribution board.

FIG. 25 is a front view of a conventional optical module.

FIG. 26 is a left side view of the conventional optical module with the inside thereof open.

FIG. 27 is a right side view of the conventional optical module with the inside thereof open.

[Explanation of symbols]

1 optical distribution board, 12 optical module, 13 module main body, 16A rear end opening, 18 hooking portion, 18a inclined surface, 19 optical connector adapter, 31 module side optical fiber, 32 optical connector plug, 33A first optical fiber ( Optical fiber core wire), 33a extra length processing unit, 3
4 connection part (fusion connection part)

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Kazuya Ogata             Fuji Co., Ltd. 1440 Rokuzaki, Sakura City, Chiba Prefecture             Kura Sakura Office F-term (reference) 2H036 QA46 RA25                 2H038 AA21 CA34 CA37 CA38                 4E352 AA08 AA16 BB02 BB07 BB10                       DR07 DR23 FF09 GG01 GG12                       GG17

Claims (3)

[Claims] 1. A thin box-shaped module body (13) is provided with an optical connector adapter (19) at a front end thereof, and is connected to the optical connector adapter in the module body via an optical connector plug (32). A module-side optical fiber (31), a first optical fiber (33A) drawn into the module body from the outside, and a connecting portion (3) between the module-side optical fiber and the first optical fiber.
4) and the optical fiber (12) in which the surplus length processing section (33a) of the first optical fiber is arranged, the rear end of the module body is opened, and the rear end opening (16A) is An optical module, characterized in that a locking part (18) for locking the extra length processing part is provided on one side. 2. The optical module according to claim 1, wherein a portion of the hooking portion (18) facing the front end side of the module body (13) is an inclined surface (18a). . 3. An optical distribution board comprising a plurality of the optical modules according to claim 1 or 2.