JP5065195B2 - Optical module and manufacturing method thereof - Google Patents

Description

  The present invention relates to a plurality of cylindrical collimator lenses or a pair of collimator lens arrays in which a plurality of optical fibers are arranged in parallel with each other, or an optical module in which optical fiber arrays are opposed to each other, and a method for manufacturing the same. The present invention relates to a method for manufacturing an optical module that enables manufacturing an optical module in which a pair of collimator lens arrays or optical fiber arrays are opposed to each other without alignment.

  A collimator lens array formed by arranging a plurality of collimator lenses in parallel with each other is used, for example, as an optical module that conducts light by making the pair of collimator lens arrays face each other.

FIG. 12 shows a pair of opposed collimator lenses 1 and an optical fiber 2 connected to the pair of collimator lenses in an optical module in which a pair of collimator lens arrays are opposed to each other. An optical element such as a filter or an optical isolator is inserted between the collimator lenses 1 facing each other.
In order to reduce the loss of optical coupling between the collimating lenses 1 facing each other, it is extremely important to align the axes of the collimating lenses 1 with each other.

  The opposing collimator lens 1 needs to be aligned with respect to the displacement in the x direction, the displacement in the y direction, the inclination θx in the x direction, and the inclination θy in the y direction in FIG. 12, and the alignment operation is complicated. Various ideas have been made to make the mind easier.

FIG. 13 illustrates a manufacturing method (Patent Document 1) that facilitates alignment between opposing collimating lenses when manufacturing opposing collimating lens arrays.
First, on a substrate 5 having an end surface that forms a plane of a collimator lens array, a long gradient index rod material 6 is arranged so that the optical axis of the gradient index rod lens 6 is parallel to one of the end surfaces. Are arranged in parallel at a predetermined pitch (FIG. 13A).
Next, the gradient index rod lens raw material is cut and divided together with the substrate 5 on a surface orthogonal to the optical axis at a predetermined interval (FIG. 13B).
Next, each of the divided gradient index rod lens raw materials is adjusted to a specified lens length, and then the cut-side end faces are made to face each other, and the optical axes between the facing lenses are made to coincide (FIG. 13 (c)). . In the figure, the substrate cut and divided is indicated by 5a. A rod lens divided from the gradient index rod lens raw material 6 and adjusted to a specified lens length is indicated by 6a. The length (L / 2) of the rod lens 6a divided by cutting is half the length (L) of the rod lens raw material 6.

In the manufacturing method described above, one long rod lens raw material 6 is cut and divided to create a pair of opposing collimator lenses 6a, 6a, and the alignment between the opposing collimator lenses is in the x direction. The alignment for the inclination θx and the inclination θy in the y direction is not necessary, and only two-axis alignment of the x-direction displacement and the y-direction displacement is required.
JP 2002-182009 (FIGS. 7 and 4, paragraph numbers [0006], [0016], etc.)

In the normal manufacturing method of the opposing collimator lens array, the long gradient index rod lens raw material 1 is cut into a predetermined lens length to produce a number of gradient index rod lenses. In the above manufacturing method, a pair of collimator lenses 6a and 6a facing each other is manufactured by cutting and dividing one long rod lens raw material 6. Alignment work is improved in that only two-axis alignment of x-direction displacement and y-direction displacement is required.
However, the alignment between the collimator lenses facing each other is an alignment operation performed while light is conducted, and this alignment operation takes a very long time, so even 2-axis alignment is extremely complicated.
In addition, the centering machine is usually expensive, about 10 million yen, and the initial investment is high, and the maintenance cost is also high.
Therefore, if such alignment work is not required, the manufacturing efficiency can be significantly improved and the manufacturing cost can be reduced.

  An optical fiber array in which a plurality of optical fibers are arranged in parallel with each other is also used as an optical module that conducts light by making the pair of optical fiber arrays face each other, but the optical fiber arrays face each other. In the case of the optical module, the alignment work is complicated as described above.

  The present invention has been made based on the above background, and when manufacturing an optical module in which a pair of collimator lens arrays or optical fiber arrays are opposed to each other, alignment work between opposed collimator lenses or optical fibers is performed. It is an object of the present invention to provide an optical module that can be made useless and a method for manufacturing the same.

The optical module of the invention of claim 1 that solves the above-mentioned problem is to accommodate a long collimator lens raw material in each positioning groove of a substrate provided with a plurality of positioning grooves parallel to each other, and fix it with an adhesive, etc. on the surface side of the substrate in the longitudinal direction of the intermediate portion of the substrate, the intermediate portion groove extending in the substrate width direction by processing including the collimator lens raw material, aligned parallel to each other a plurality of cylindrical collimator lens a pair of collimating lens array comprising Te to prepare a first optical module are opposed,
Fixed with adhesive or the like accommodates a respective lengths have optical fiber to each of the positioning grooves of the substrate provided with a plurality of parallel positioning grooves each other, then the surface side of the substrate in the longitudinal direction of the intermediate portion of the substrate, the substrate A second optical module in which a pair of optical fiber arrays formed by processing an intermediate groove extending in the width direction including the optical fiber to face each other and arranging a plurality of optical fibers in parallel with each other is manufactured ,
The first optical module has a structure in which the first optical module is fitted in an intermediate groove of the second optical module.

According to a second aspect of the present invention , there is provided an optical module manufacturing method in which a long collimator lens raw material is accommodated in each positioning groove of a substrate provided with a plurality of positioning grooves parallel to each other and fixed with an adhesive or the like, and then the substrate on the surface side of the substrate in the longitudinal direction of the intermediate portion of the intermediate portion groove extending in the substrate width direction by processing including the collimator lens raw material, comprising a plurality of cylindrical collimator lens aligned parallel to each other a pair of collimating lens array to produce a first light module are opposed,
Fixed with adhesive or the like accommodates a respective lengths have optical fiber to each of the positioning grooves of the substrate provided with a plurality of parallel positioning grooves each other, then the surface side of the substrate in the longitudinal direction of the intermediate portion of the substrate, the substrate A second optical module in which a pair of optical fiber arrays formed by processing an intermediate groove extending in the width direction including the optical fiber to face each other and arranging a plurality of optical fibers in parallel with each other is manufactured,
At that time, the groove width of the intermediate portion grooves of the second optical module suit substrate longitudinal dimension of the first optical module and the first substrate positioning groove pitch and a second optical module of an optical module When the first optical module is fitted into the intermediate groove of the second optical module, and the positioning groove pitch of the second optical module is matched. The collimator lens height position of the first optical module and the optical fiber height position of the second optical module are set to the same depth, and the first optical module is fitted into the intermediate groove of the second optical module. It is characterized by making it.

According to the first or second aspect of the present invention, the first optical module and the second optical module are respectively intermediate in a state in which a long collimator lens raw material or an optical fiber is accommodated and fixed in each positioning groove of the substrate. Since it is a structure which processes a part groove including a collimator lens raw material or an optical fiber, a pair of opposing collimator lenses or optical fibers formed by the processing of the intermediate part groove coincide with each other. There is no need to realign.
Since such a complicated alignment work is not required, the lead time at the time of manufacturing the optical module can be shortened, and the cost can be reduced.
In addition, since a pair of collimator lenses or optical fibers facing each other in an optical module is a single collimator lens raw material or optical fiber originally housed and fixed in the same positioning groove, not only alignment is not necessary, There is very little misalignment between collimator lenses or optical fibers. As a result, the deviation of the optical axis can be extremely reduced, and a low-loss optical connection is possible.
In addition, since expensive equipment such as an alignment device is not required, the initial cost and maintenance cost of such equipment are not required, and the cost can be reduced in this respect.

In addition, according to the first or second aspect of the present invention, the axial misalignment between the collimating lenses facing each other is extremely small and the axial misalignment between the optical fibers connected to the rear end face of each collimating lens is not required. However, an optical module having a very small structure can be obtained.

  Hereinafter, an optical module embodying the present invention and a manufacturing method thereof will be described with reference to the drawings.

1 to 3 are perspective views sequentially showing a procedure for manufacturing the first optical module in the optical module of one embodiment of the present invention.
First, as shown in FIG. 1, a substrate 11 having a plurality of positioning grooves, for example, V-grooves 11a parallel to each other is manufactured.
Next, as shown in FIG. 2, the raw material 12 of the cylindrical collimator lens is accommodated in each V groove 11a of the substrate 11 and fixed with an adhesive or the like. The collimator lens raw material 12 is a gradient index rod lens.
Next, as shown in FIG. 3, an intermediate groove 13 extending in the substrate width direction is processed on the surface side of the substrate 11 in the intermediate portion in the longitudinal direction of the substrate 11 including the collimator lens raw material 12.
Here, the intermediate groove 13 includes not only a groove portion formed in the substrate 11 but also a gap portion formed by cutting and removing the intermediate portion of the collimator lens. Both side wall surfaces (opposite surfaces of the collimator lens 12a and both wall surfaces of the groove portion of the substrate 11) 13a of the intermediate groove 13 are vertical.
An appropriate means such as cutting or grinding may be employed for processing the intermediate groove 13.
Thus, an optical module 15 is obtained in which a pair of collimator lens arrays 14 formed by arranging a plurality of collimator lenses 12a in parallel with each other are opposed to each other.

The optical module 15 has a structure in which the intermediate groove 13 is processed including the collimator lens raw material 12 in a state where the long collimator lens raw material 12 is accommodated and fixed in each V groove 13 of the substrate 11. The axis centers of the pair of collimator lenses 12a facing each other formed by processing the intermediate groove 13 coincide with each other, and it is not necessary to perform alignment again.
Since such a complicated alignment work is not required, the lead time at the time of manufacturing the optical module can be shortened, and the cost can be reduced.
Further, since the pair of collimator lenses facing each other in the optical module is originally one collimator lens raw material 12 accommodated and fixed in the same V-groove, not only alignment is not necessary, but also between the collimator lenses 12a. There is very little misalignment. As a result, the deviation of the optical axis can be extremely reduced, and a low-loss optical connection is possible.
In addition, since expensive equipment such as an alignment device is not required, the initial cost and maintenance cost of such equipment are not required, and the cost can be reduced in this respect.

The optical module 15 is used by connecting, for example, an optical fiber 16 to the rear end face of each collimator lens 12a as shown by a two-dot chain line in FIG.
Although not shown, an optical element such as a filter or an optical isolator is inserted between the collimator lenses 12a facing each other.

The procedure for manufacturing the second optical module in the optical module of the embodiment of the present invention sequentially in FIGS. 5 to 7 showing in a perspective view.
First, as shown in FIG. 5, a substrate 21 having a plurality of positioning grooves, for example, V-grooves 21a parallel to each other is manufactured.
Next, as shown in FIG. 6, a long optical fiber 22 is accommodated in each V groove 21a of the substrate 21 and fixed with an adhesive or the like.
Next, as shown in FIGS. 7 and 8, an intermediate groove 23 extending in the substrate width direction is processed on the surface side of the substrate 21 in the intermediate portion in the longitudinal direction of the substrate 21 including the long optical fiber 22.
Here, the intermediate groove 23 includes not only the groove portion formed in the substrate 21 but also the gap portion formed by cutting and removing the intermediate portion of the optical fiber 22 as described above. Both side wall surfaces of the intermediate groove 23 (opposite surfaces of the divided optical fiber 22a and both wall surfaces of the groove portion of the substrate 21) 23a are vertical.
For the processing of the intermediate groove 23, an appropriate means such as cutting or grinding may be employed as described above.
Thus, an optical module 25 is obtained in which a pair of optical fiber arrays 24 formed by arranging a plurality of optical fibers 22a in parallel with each other are opposed to each other.

In the optical module 25 described above, the axis centers of the pair of optical fibers 22a facing each other coincide with each other, and there is no need to perform alignment again.
In addition, although the details are omitted, the same effects as those described for the optical module 15 can be obtained.

FIG. 10 is a perspective view of an optical module 35 according to an embodiment of the present invention, and FIG. 11 is a longitudinal sectional view of the optical module 35 of FIG.
The optical module 35 of this embodiment is manufactured in the manner described with reference to FIGS. 5 to 8 while the optical module 15 having a structure in which the collimator lens 12a manufactured in the manner described with reference to FIGS. In this structure, the groove width of the groove 23 ′ is widened, and the optical fiber 22a ′ is opposed to the intermediate portion groove 23 ′ in the optical module 25 ′.

The process for manufacturing the optical module 35 will be described. First, the first optical module 15 with the collimator lens 12a facing is manufactured in the manner described with reference to FIGS. In the illustrated example, the optical module 15 is the same as the optical module 15 shown in FIGS.
On the other hand, the second optical module 25 ′ having a structure in which the optical fiber 22a ′ is opposed to each other and the groove width of the intermediate groove 23 ′ is widened as shown in FIG. Make it.
The groove width W of the intermediate groove 23 ′ of the second optical module 25 ′ matches the substrate length dimension w of the first optical module 15. That is, the dimensions are such that the first optical module 15 fits into the intermediate groove 23 ′ of the second optical module 25 ′ as shown in FIGS.
Further, the pitch of the V-groove 11a of the substrate 11 of the first optical module 15 and the pitch of the V-groove 21a ′ of the substrate 21 of the second optical module 25 ′ are matched, and the middle of the second optical module 25 ′. The depth H of the groove 23 ′ is set so that the collimator lens height position of the first optical module 15 when the first optical module 15 is fitted into the intermediate groove 23 ′ of the second optical module 25 ′. And a depth at which the optical fiber height position of the second optical module matches.

When the first optical module 15 is fitted into the intermediate groove 23 ′ of the second optical module 25 ′ produced as described above, they are arranged in parallel to each other as shown in FIGS. An optical module 35 having a structure in which the optical fiber collimator arrays 34 each provided with the collimator lens 12a at the tips of the plurality of optical fibers 22a 'face each other is obtained.
According to the optical module 35, the axial misalignment between the collimator lenses 12a facing each other is very small and the axial misalignment between the optical fibers 22a connected to the rear end face of each collimator lens 12a is very small without alignment work. An optical module having a structure is obtained.

  In the optical module 35 described above, the axis alignment between the optical fiber 22a ′ and the collimator lens 12a in the pair of optical fiber collimator arrays 34 facing each other is omitted, but for example, the first optical module 15 A V-shaped ridge is formed on the bottom surface, a V-groove is formed at a position corresponding to the V-shaped ridge in the intermediate groove 23 ′ of the second optical module 25 ′, and the V on the first optical module 15 side is formed. It is conceivable to align the axis by fitting the convex ridge into the V groove on the second optical module 25 'side.

In addition, regarding the axis alignment between the optical fiber 22a ′ and the collimator lens 12a, it is conceivable to adopt a configuration as described in FIG. 6 and paragraph numbers [0024] to [0030] in Patent Document 1.
That is, the light propagating through the long gradient index rod lens propagates repeatedly by expanding and converging the light beam diameter, but the pitch P, which is the expansion and condensing period of the light beam diameter, is taken into consideration. Although lengths L _1, L ₂ of a pair of collimating lenses 12a that faces in FIG. 11 are shown equally, as shown in FIG. 6 in Patent Document 1, the opposing one of the collimator lens 12a a length L ₁ a 3/4 pitch (3P / 4), to the other of the collimating lens 12a of length _{L 2} and a quarter of the pitch (P / 4). As a result, even if there is a slight misalignment between the optical fiber 22a ′ and the collimator lens 12a, the optical coupling loss can be reduced.

BRIEF DESCRIPTION OF THE DRAWINGS The point which manufactures the 1st optical module in the optical module of one Example of this invention is demonstrated, it is a figure of the first step in a manufacturing process, and is a perspective view of the board | substrate which provided the V-groove. FIG. 2 is a perspective view of a rod lens raw material integrated substrate in a stage subsequent to FIG. 1 in the optical module manufacturing process, in which a rod lens raw material is accommodated and fixed in each V groove of the substrate of FIG. 1. It is a perspective view of the optical module obtained by giving a groove process to the rod lens raw material integrated substrate of FIG. It is the longitudinal cross-sectional view shown in the state which joined the optical fiber to the optical module of FIG. BRIEF DESCRIPTION OF THE DRAWINGS The point which manufactures the 2nd optical module in the optical module of the Example of this invention is demonstrated , it is a figure of the first step in a manufacturing process, and is a perspective view of the board | substrate which provided the V-groove. FIG. 6 is a perspective view of a rod lens raw material integrated substrate in which a rod lens raw material is accommodated and fixed in each V groove of the substrate of FIG. 5. It is a perspective view of the optical module obtained by giving a groove process to the rod lens raw material integrated substrate of FIG. It is a longitudinal cross-sectional view of the optical module of FIG. It is a perspective view of the optical module with the wide width | variety of the center part groove | channel produced like the optical module of FIGS. It is a perspective view of the optical module produced by fitting the optical module of FIGS. 1-4 in the center part groove | channel of the optical module of FIG. It is a longitudinal cross-sectional view of the optical module of FIG. It is a figure explaining the structure where a pair of optical fiber collimator formed by connecting the collimator lens which is a refractive index distribution type | mold rod lens to the optical fiber was made to oppose. It is a perspective view explaining the conventional method of manufacturing the optical module which made a pair of collimator lens array oppose.

Explanation of symbols

11, 21 Substrate 11a, 21a V groove (positioning groove)
12 Collimator Lens Raw Material 12a Collimator Lenses 13, 23 Intermediate Groove 13a, 23a Wall Surface 14 (Intermediate Groove) Collimator Lens Array
15 Optical module (first optical module)
25 Optical module
25 'second optical module
35 Optical module 16 Optical fiber 22 Long optical fibers 22a and 22a ′ (before intermediate groove processing) Optical fiber 24 Optical fiber array

Claims (2)

A long collimator lens raw material is accommodated in each positioning groove of the substrate provided with a plurality of positioning grooves parallel to each other and fixed with an adhesive or the like, and then on the surface side of the substrate in the middle portion in the longitudinal direction of the substrate, the intermediate portion groove extending in the substrate width direction by processing including the collimator lens raw material, a first in which a plurality of cylindrical collimator lens are opposed to a pair of collimator lens array formed by parallel aligned to each other to produce an optical module,
Fixed with adhesive or the like accommodates a respective lengths have optical fiber to each of the positioning grooves of the substrate provided with a plurality of parallel positioning grooves each other, then the surface side of the substrate in the longitudinal direction of the intermediate portion of the substrate, the substrate the intermediate portion grooves extending in the width direction by processing including the optical fiber, to prepare a plurality of second optical module made to face the optical fiber array 1 pair of aligned parallel to each other the optical fiber,
An optical module having a structure in which the first optical module is fitted in an intermediate groove of the second optical module. A long collimator lens raw material is accommodated in each positioning groove of the substrate provided with a plurality of positioning grooves parallel to each other and fixed with an adhesive or the like, and then on the surface side of the substrate in the middle portion in the longitudinal direction of the substrate, the intermediate portion groove extending in the substrate width direction by processing including the collimator lens raw material, a first in which a plurality of cylindrical collimator lens are opposed to a pair of collimator lens array formed by parallel aligned to each other Make an optical module,
Fixed with adhesive or the like accommodates a respective lengths have optical fiber to each of the positioning grooves of the substrate provided with a plurality of parallel positioning grooves each other, then the surface side of the substrate in the longitudinal direction of the intermediate portion of the substrate, the substrate A second optical module in which a pair of optical fiber arrays formed by processing an intermediate groove extending in the width direction including the optical fiber to face each other and arranging a plurality of optical fibers in parallel with each other is manufactured,
At that time, the groove width of the intermediate portion grooves of the second optical module suit substrate longitudinal dimension of the first optical module and the first substrate positioning groove pitch and a second optical module of an optical module When the first optical module is fitted into the intermediate groove of the second optical module, and the positioning groove pitch of the second optical module is matched. The collimator lens height position of the first optical module and the optical fiber height position of the second optical module are set to the same depth, and the first optical module is fitted into the intermediate groove of the second optical module. An optical module manufacturing method characterized by comprising:

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