JP3007827B2 - Optical fiber array assembly method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for assembling an optical fiber array having polarization maintaining optical fibers arranged at a small interval.

[0002]

2. Description of the Related Art A polarization-maintaining optical fiber is used for measuring a waveguide of an optical fiber gyroscope or an optical fiber interferometer, or for coherent communication or a transmission line of an optical integrated circuit. FIG. 12 is a diagram showing a cross section of an example of the polarization-maintaining optical fiber. In FIG. 12, the polarization-maintaining single-mode fiber (15) comprises an elliptical core (84) at the center and a cladding (83) surrounding the core (84). Along the axis is a polarization preserving surface (82). When polarized light is incident on the polarization preserving surface (82), the polarized light is retained.

The polarization-maintaining optical fiber (15) has a polarization-maintaining surface (82) determined by its cross-sectional structure. It is necessary that the polarization maintaining surfaces (82) in both cross sections of the polarization maintaining optical fiber (15) to be matched. Therefore, when trying to connect the polarization-maintaining optical fiber (15) by the optical fiber array (16),
The polarization maintaining optical fiber (15) is connected to the optical fiber array (1).
It is necessary to set the polarization preserving surface (82) when set to 6) so as to match a predetermined reference value, and it is necessary to measure the polarization preserving surface (82).

FIG. 13 is a view for explaining an example of a method for measuring the polarization maintaining plane of the polarization maintaining optical fiber. In FIG. 13, (91) is a light source, (92) is a polarizer,
(15) is a polarization-maintaining optical fiber to be measured, (94)
Is an analyzer, (95) is an optical sensor, and (96) is an optical power meter. In the apparatus having the above-described configuration, the polarizer (9
2) With the polarized light incident on the polarization preserving optical fiber (15) so that the polarized light passed through 2) is incident thereon, the analyzer (94) is rotated and the output of the optical power meter (96) is maximized. Is obtained as a polarization preserving surface. When assembling as an optical fiber array, the end face of the polarization preserving optical fiber (15) is rotated and fixed so that the obtained polarization preserving plane coincides with a reference plane, for example, a horizontal plane.

In an optical fiber gyroscope or the like, a polarization-maintaining optical fiber is drawn out as one optical fiber of a two-core optical fiber array to form an optical fiber coil,
Return to the optical fiber array as another core. However,
In the conventional method for measuring the polarization maintaining surface described above, both end surfaces of the optical fiber need to be separated from each other, and when both end surfaces of the optical fiber are close to the optical fiber array targeted by the present invention. Was impossible. Therefore, after separately measuring the two-core optical fibers on the optical fiber array using the conventional method for measuring the polarization preserving surface and matching the two optical fibers on the optical fiber array to a predetermined reference value, ,
The other ends of these optical fibers were fused together to form an optical fiber coil. When the other ends of the optical fibers are fused together, it is necessary to match the polarization preserving surfaces of the optical fibers, and fusion is performed with the polarization preserving surfaces of the optical fibers accurately matched. It was difficult to do. The fusion of the optical fibers is performed by melting the ends of the optical fibers by electric discharge. In this case, it is necessary to remove the bending and twisting of the optical fiber that causes the polarization preserving surface (82) to be inconsistent, and to remove the dirt that causes the adhesive strength to decrease. Also, it is necessary to set good fusion conditions.

In order to rotate the optical fiber, the optical fiber is gripped by an optical fiber rotating holder, mounted in a fixing groove of the optical fiber array, the polarization preserving surface is adjusted, and a thermosetting adhesive is dropped thereon. Then, a lid of an optical fiber array is placed thereon, and the adhesive is cured.

Conventionally, an optical fiber has been vacuum-adsorbed to a proximity fiber holder and mounted using a microscope or a magnifying glass from above the fixing groove of the substrate of the narrow pitch optical fiber array. When arranging optical fibers at a pitch of 250 μm by this method, it is necessary to lower the optical fibers in parallel with the fixing grooves of the substrate of the optical fiber array, and in many cases, the tip of the optical fibers is directly tweezers or the like. It is necessary to fine-tune the position of the optical fiber with respect to the fixing groove,
It required the skill of the worker and required many man-hours.

Conventionally, the rotation of the polarization-maintaining optical fiber is
A fiber rotation holder that fixes the optical fiber jacket by magnetic force, fixes the optical fiber cladding by vacuum, rotates the optical fiber jacket by a stepping motor, and also rotates the optical fiber cladding adsorbed by the vacuum. Was used. But,
When two fiber rotation holders are juxtaposed and two polarization-maintaining optical fibers arranged in parallel are rotated, the pitch of the fiber rotation holders is at least 40 mm. Therefore, the required optical fiber spacing is 40 m
m or less, the side-by-side fiber rotation holder
This is achieved by bending the optical fiber, fixing the optical fiber jacket portion by the magnetic force method as described above, and arranging the fiber rotating holders in a C shape as shown in FIG. 10m from required optical fiber spacing
It has been difficult to stably rotate the optical fiber jacket to the tip of the optical fiber by rotating the wide portion of the optical fiber jacket curved by m or more. This is because the rotational force is not sufficiently transmitted because the curvature of the optical fiber is too large.

Further, after adjusting the polarization preserving surface, a thermosetting adhesive is dropped, and a lid of an optical fiber array is placed thereon, and the adhesive is cured. The wave storage surface may shift. Furthermore, since the thermosetting adhesive is dropped while the optical fiber is mounted in the fixing groove of the optical fiber array, the amount of the thermosetting adhesive is not constant, and when the lid is covered, the thermosetting adhesive is not applied. If the amount of the agent was too large, it protruded into the substrate, and if the amount of the thermosetting adhesive was too small, a problem such as insufficient adhesion of the lid occurred, resulting in problems of readjustment man-hours and defective products. . In addition, the stability of the mutual bonding form of the optical fiber array substrate, the optical fiber, and the lid of the optical fiber array tends to cause a problem.

[0010]

SUMMARY OF THE INVENTION The present invention has been made in view of such circumstances, and it is an object of the present invention to provide an optical fiber guide groove or optical fiber guide hole, not from above. By sliding the optical fiber easily from the side along the edge, the tips can be aligned at a narrow pitch and finally can be securely set in the fixing groove of the substrate of the optical fiber array.
It responds to demands for improving productivity.

In addition, a method for measuring the polarization preserving surfaces at both ends of the optical fiber coil while forming the optical fiber coil of the polarization preserving optical fiber in which both ends of the optical fiber coil are juxtaposed to the optical fiber array is found. Accordingly, an object is to increase the productivity and eliminate the connection loss of light at the fused portion.

The present invention also satisfies a demand for enabling rotation adjustment of two polarization-maintaining fibers arranged at a narrow interval.

Further, it is an object of the present invention to improve the operating efficiency of the assembling apparatus by enabling the thermosetting adhesive to be cured off-line.

[0014]

In order to solve the above-mentioned problems, a method for assembling an optical fiber array according to the present invention comprises: a substrate having a fixing groove formed therein for receiving and positioning an optical fiber; In the method for assembling an optical fiber array comprising a polarization-maintaining optical fiber mounted on the optical fiber and a lid covering the optical fiber, the optical fiber is mounted on the fixing groove, and a thermosetting adhesive is disposed. A lid is placed on the substrate on which the optical fiber is mounted, and by applying pressure to the lid placed on the substrate, the thermosetting adhesive is applied to the gap between the optical fiber, the substrate and the lid. To release the pressure applied to the lid, measure the polarization preserving surface of the optical fiber, and rotate the optical fiber to adjust the polarization preserving surface to a predetermined angle. Apply pressure and It is characterized in that curing the thermosetting adhesive state. Further, using an optical fiber guide mechanism, the optical fiber is mounted in the fixing groove, a thermosetting adhesive is applied to the back surface of the lid, and the lid is placed on the substrate on which the optical fiber is mounted. And applying pressure to the lid placed on the substrate to cause the thermosetting adhesive to flow through the gap between the optical fiber, the substrate and the lid, and release the pressure applied to the lid. Then, the polarization preserving surface of the optical fiber is measured, and by rotating the optical fiber, the polarization preserving surface is adjusted to a predetermined angle, pressure is applied to the lid, and the thermosetting bonding is performed in that state. It is characterized by curing the agent.

According to the method of assembling the polarization-maintaining optical fiber array of the present invention, since a thermosetting adhesive is applied to the side of the lid having a flat surface, a uniform amount of liquid can be touched. Using an optical fiber guide mechanism, an optical fiber is mounted, the lid is temporarily held down, and a thermosetting adhesive is caused to flow into the gap between the optical fiber, the optical fiber array substrate and the lid of the optical fiber array. Since the rotation of the wave preserving surface is adjusted, the polarization preserving surface is determined accurately, and a lubricating effect of the thermosetting adhesive is generated, so that a smooth rotating state can be obtained.

Preferred embodiments of the optical fiber guide mechanism according to the above invention include the following. A first method is an optical fiber guide groove in which a groove width dimension at a front end is slightly larger than a diameter of the optical fiber, and a groove width at a rear end is a wide planar funnel shape. A jig comprising at least one vacuum suction hole for suctioning the optical fiber, mounting the front end of the optical fiber from the wide end of the rear end of the optical fiber guide groove of the jig, and passing through the vacuum suction hole. And preventing the floating of the optical fiber by advancing the tip of the optical fiber along the optical fiber guide groove.

The width of the groove at the front end is slightly larger than the diameter of the optical fiber, and the width of the groove at the rear end is a flat funnel-shaped optical fiber guide groove. The initial positioning is very easy because it can be inserted from the wide end of the funnel-shaped rear end.
Also, after positioning, if the optical fiber is pushed toward the funnel-shaped tip, the tip of the optical fiber proceeds along the funnel-shaped optical fiber guide groove, and is securely mounted in the fixing groove of the optical fiber array substrate. . Further, by using a jig provided with at least one vacuum suction hole for sucking the optical fiber to the optical fiber guide groove,
When the optical fiber is vacuum-sucked and the optical fiber is pushed in, the floating of the optical fiber is prevented, and smooth mounting becomes possible.

The second method uses a jig provided with a funnel-shaped optical fiber guide hole having a hole diameter at the front end slightly larger than the diameter of the optical fiber and a large hole at the rear end. This is a method of inserting the tip of the fiber from the funnel-shaped mouth at the rear end of the jig.

The hole diameter at the front end is slightly larger than the diameter of the optical fiber, and the hole diameter at the rear end is a wide funnel-shaped optical fiber guide hole. Can be inserted from the rear end, so that initial positioning is extremely easy. After positioning, if the optical fiber is pushed toward the funnel-shaped tip, the tip of the optical fiber advances along the funnel-shaped guide hole and is securely mounted in the fixing groove of the optical fiber array substrate.

By inserting the optical fiber array substrate so that the optical fiber insertion side of the mounting portion is lower than the opposite side of the optical fiber insertion side, the optical fiber
It is possible to perform the operation smoothly without the tip of the optical fiber coming into contact with the end face of the substrate of the optical fiber array.

Preferred embodiments of the method for measuring the polarization maintaining surface of the polarization maintaining optical fiber according to the present invention include the following. In the first method, as shown in FIG. 6, light from a light source is incident on one end face of a polarization-maintaining optical fiber in which both ends of an optical fiber coil are juxtaposed to an optical fiber array via a first lens. And a method of measuring the polarization preserving surface of the optical fiber with a photodetector through a second lens, the light emitted from the other end of the polarization preserving optical fiber, wherein the optical fiber coil has one end surface thereof. An image of the light source substantially forms an image, and light from the light source does not enter the other end of the polarization-maintaining single-mode fiber, and an image of the other end of the polarization-maintaining single-mode fiber is a light-receiving surface of the photodetector. This is a method using an optical system that forms an image substantially at a position. The second method is a method in which the first lens and the second lens are integrated as shown in FIG. Further, a third method includes providing a beam splitter between the first lens, the second lens, and the photodetector, and transmitting light emitted from the other end of the optical fiber to the second lens. In this method, the light is incident on the photodetector via the beam splitter, and light from the light source is incident from a branching direction of the beam splitter.

By accurately focusing the second lens on the photodetector, the measurement accuracy of the polarization preserving surface can be improved.

The illumination light is condensed on the light incident end face of the polarization-maintaining optical fiber by preventing the incident illumination axis of the light source from being coincident with the axis of the optical path of the imaging side optical system of the photodetector from the other end of the optical fiber. In addition, it is possible to prevent the epi-illumination from hitting the observation end face of the polarization-maintaining optical fiber. As a result, a large amount of light can be incident on the light incident end face of the polarization-maintaining optical fiber, and only the polarized light incident on the light incident end face is emitted from the observation end face of the polarization-maintaining optical fiber. High measurement is possible.
Further, the measurement of the polarization preserving surface can be performed by a combination of a polarizing filter and a power meter in addition to the above-described pattern recognition using the CCD or the like.

A preferred embodiment of the method for rotating a polarization-maintaining optical fiber according to the present invention is a method for rotating and adjusting the polarization-maintaining surface to a predetermined angle without changing the position of the optical fiber. The optical fiber is sandwiched between the upper sandwiching plate and the lower sandwiching plate in a direction perpendicular to the longitudinal direction, and the upper sandwiching plate and the lower sandwiching plate are perpendicular to the longitudinal direction of the polarization-maintaining optical fiber, This is a method of sliding the same distance in opposite directions.

Preferred modes of the method of sliding the upper holding plate and the lower holding plate by the same distance in a direction perpendicular to the longitudinal direction of the polarization-maintaining optical fiber and in directions opposite to each other are as follows. . In the first method, a first eccentric cam and a second eccentric cam which are eccentric with respect to an axis in the opposite directions to each other by the same distance are provided at an interval between the upper sandwiching plate and the lower sandwiching plate. The provided shaft, the upper sandwiching plate penetrates the shaft, a first hole into which the first eccentric cam is fitted, and the lower sandwiching plate corresponding to the upper sandwiching plate, penetrates the shaft. And a second hole in which the second eccentric cam is fitted. A second method includes a first linear displacement cam and a second linear displacement cam which are eccentric with respect to the axis in the directions opposite to each other by the same distance.
A shaft provided with a linear displacement cam at an interval between the upper sandwiching plate and the lower sandwiching plate, and a third hole through which the upper sandwiching plate penetrates the shaft and fits the first linear displacement cam. A method of using a jig, wherein the lower holding plate has a fourth hole corresponding to the upper holding plate, through which the shaft penetrates, and into which the second linear displacement cam is fitted. Here, the shape of the first to fourth holes into which the cams are fitted is such that the inner peripheral surface has a flat surface on which the outer peripheral surface of the cam slides, and has a size that allows the cam to rotate.

In the method of rotating a polarization-maintaining single-mode optical fiber according to the present invention, the optical fiber is sandwiched between the upper sandwiching plate and the lower sandwiching plate, and the upper sandwiching plate and the lower sandwiching plate slide by the same distance in opposite directions. By rotating the optical fiber without changing the position of the optical fiber set initially, the polarization preserving surface can be adjusted to a predetermined angle. Therefore, by arranging the rotating jigs side by side, it is possible to adjust each polarization preserving surface without changing the optical fiber interval initially set. Further, there are the following mechanisms for sliding the two plates by the same distance in opposite directions. The first method is to rotate a shaft provided with a first eccentric circular cam and a second eccentric circular cam which are eccentric with respect to the axis in the directions opposite to each other by the same distance, and The first eccentric circular cam and the second eccentric circular cam press the flat portions on the side surfaces of the holes formed in the plate and the second plate, respectively, so that the two plates are in the same direction in opposite directions. This is a method that enables dimensional sliding.

In the second method, a linear displacement cam is used instead of the eccentric circular cam, so that the relationship between the rotation angle of the cam and the rotation angle of the optical fiber becomes linear, and the rotation angle can be adjusted. It is a way to make it easier. If the upper sandwiching plate and the lower sandwiching plate slide by 0.5πr at the maximum, it is possible to adjust to a predetermined polarization preserving surface, thereby enabling rotation adjustment of two polarization preserving optical fibers arranged at a narrow interval. be able to. Therefore, when the radius r of the polarization-maintaining single-mode fiber is 100 μm, the required slide size of the upper holding plate and the lower holding plate is about 157 μm. The interval between the polarization-maintaining single-mode fibers held by the two sets of the upper sandwiching plate and the lower sandwiching plate is 10 mm or less, preferably 5 mm or less, more preferably 5 mm or less, from the required optical fiber spacing. The interval is the same as the interval. This is because, as the curvature increases, the rotational force is not sufficiently transmitted, and it becomes difficult to rotate the optical fiber to the tip end stably.

Further, pressure is applied to the lid according to the above invention,
In a preferred embodiment of the method of curing the thermosetting adhesive in that state, there is a method in which a portion for mounting the substrate of the optical fiber array uses a separate jig. By setting the part on which the optical fiber array is mounted as a jig separate from the main body, the thermosetting adhesive can be cured off-line.

[0029]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a flow chart for assembling an optical fiber array according to the present invention. FIG. 2 shows a substrate (18) of a two-core collectively aligned optical fiber array having a pitch of 250 μm and an optical fiber (1) having a diameter of 200 μm.
5 shows a first example of a jig to which two pieces are mounted. The width of the front end of the funnel-shaped groove was 220 μm, the width of the rear end of the funnel-shaped groove was 1000 μm, and the depth of the groove was 250 μm in a U-shaped cross section. 0.1 mm diameter vacuum suction holes (7, 8,
9, 10). Their degree of vacuum is 100mmHg
４００400 mmHg. First, one end of the first optical fiber (15) is inserted into one of the funnel-shaped optical fiber guide grooves (3) capable of aligning the optical fibers at a narrow pitch, and one end of the second optical fiber (15) is inserted. It is inserted into the other one of the funnel-shaped optical fiber guide grooves (37). The two optical fibers (15) were fixed by the vacuum suction holes (7, 8, 9, 10).

Conventionally, an optical fiber is vacuum-adsorbed to an optical fiber holder for proximity and mounted using a microscope or a magnifying glass from above the fixing groove (V groove) of the substrate of the collectively aligned optical fiber array. In the case of the conventional method in which the tip of the optical fiber is finely adjusted directly with tweezers or the like, it takes one
It took 20 seconds, but when using the jig of the present invention, 3
It became possible to wear two in 0 seconds. In the above, the cross-sectional shape of the optical fiber guide groove was described in a U-shape, but the present invention is not limited to the U-shape.
Other suitable shapes such as a letter shape and a V shape may be used. Also,
The present invention is not limited to the case where the depth of the groove is constant.

Next, FIG. 3 shows a substrate (18) of a two-core collectively aligned optical fiber array having a pitch of 250 μm having a diameter of 200 μm.
9 shows a second example of a jig for mounting two μm optical fibers (15). As in the first example, the substrate (18) of the two-core batch-aligned optical fiber array having a pitch of
m optical fibers (15). The width of the front end of the funnel-shaped guide hole was 220 μm and the height was 250 μm, and the rear end of the funnel-shaped groove had a width and a height of 1000 μm. Although the cross-sectional shape of the optical fiber guide hole has been described as a rectangle, the present invention is not limited to a rectangular shape, and the cross-sectional shape of the guide hole may be any other suitable shape such as a circle, an ellipse, and a triangle.

FIG. 4 is a perspective view of a portion where the optical fiber is inserted into the fixing groove of the substrate of the optical fiber array. As shown in FIG. 5, when the optical fiber is slid along the optical fiber guide groove, the tip of the optical fiber array is collectively aligned. The optical fiber array has an inclination of 0.7 degrees with respect to the horizontal plane so as not to hit the end face of the substrate (18) of the optical fiber array, and the height of the fixing groove on the insertion side becomes 50 μm lower than the height of the optical fiber guide groove. I did it. This allows
The tip of the optical fiber inserted through the optical fiber guide groove was prevented from hitting the end face of the substrate of the optical fiber array.

A two-component thermosetting adhesive is applied to the back side of the lid of the optical fiber array by a drip touch method, and placed on the optical fiber array substrate (18). Push rod (43) shown in FIG.
The two-part thermosetting adhesive is caused to flow such that there is no gap between the optical fiber, the substrate and the lid by applying pressure to the lid of the optical fiber array. Next, the push rod (43) is raised so that the optical fiber can be rotated. When raising the push rod (43), a spring (45) provided on the push rod (43) can be used.

FIG. 8 is a diagram showing an embodiment of the method for observing the end face of an optical fiber on a collectively aligned two-core optical fiber array according to the present invention. (21) is an optical fiber coil to be measured, (22) is an objective lens common to the first lens and the second lens, (23) is a beam splitter, (24) is a CCD camera, 27) is a white light source. In the device having the above-described configuration, white light emitted from the white light source (27) is incident on one end face (end face of the incident optical fiber) (21a) of the polarization maintaining optical fiber via the beam splitter (23) and the objective lens (22). In this state, the other end surface of the polarization-maintaining optical fiber 1 (the end surface of the output optical fiber) (2)
1b), the objective lens (22), the beam splitter (2)
3) Magnify through (3) and take an image with a CCD camera (24). The captured image is subjected to image processing in the image processing apparatus, and is displayed together with the polarization storage surface (82) obtained on the monitor. The position of the white light source (27) is adjusted so that the incident light is focused on the incident optical fiber end face (21a). Further, the position of the CCD camera (24) is such that the outgoing light from the outgoing optical fiber end face (21b) is
Adjust to focus on 4).

Next, as shown in FIG. 2, the upper holding plate (35) and the lower holding plate of the first rotating jig for rotating the first optical fiber (15) are connected to a vacuum suction hole (7). The second optical fiber (21) provided between the second optical fiber (21) and the vacuum suction hole (8).
The upper sandwiching plate and the lower sandwiching plate for rotating the second rotating jig are provided between the vacuum suction holes (9) and the vacuum suction holes (10).
The distance between the vacuum suction holes (7) and (9) and the distance between the vacuum suction holes (8) and (10) are 1 m.
m. The rotary jig includes a first linear displacement cam (31) and a second linear displacement, which are eccentric and have the same distance in opposite directions with respect to the cam shaft (30) as shown in FIGS. And a cam (32). The cam diagrams of these cams are shown in FIG. A third hole (28) and a fourth hole (2) formed in the upper sandwich plate (35) and the lower sandwich plate (37), respectively.
The outer peripheral surface of the cam was slid on the inner peripheral surface of 9). FIG. 10C shows the shapes of the third hole (28) and the fourth hole (29). A first linear displacement cam (31) and a second linear displacement are respectively provided on the plane portions of the inner peripheral surfaces of the third and fourth holes formed in the upper holding plate (35) and the lower holding plate (37). A through hole is provided in the side surface of the upper sandwiching plate (35) and the lower sandwiching plate (37) so that the outer peripheral surface of the cam (32) is always at a fixed position, and a coil spring is provided in the through hole. 39), the first linear displacement cam (31) and the second linear displacement cam (32) were pressed.

The mounting portion of the optical fiber array was made a jig separate from the assembly apparatus main body, and the separate jig was used as a curing jig (12). The width of the optical fiber guide groove of the curing jig at the mating surface of the curing jig and the assembly apparatus main body is 330 μm, and the width of the wall between the optical fiber guide grooves is 50 μm.
μm, the width of the guide groove of the assembly apparatus main body was 230 μm, and the width of the wall between the optical fiber guide grooves was 150 μm so that the tip of the inserted optical fiber did not hit the end face of the curing jig. The fixing of the curing jig to the assembly apparatus main body was performed using vacuum suction. The substrate of the optical fiber array is placed at a predetermined position by a side positioning plate, and fixed by vacuum suction from the side surface and the lower surface.

The curing jig and the vacuum system holding the substrate of the optical fiber array are stopped, and the curing jig is removed from the main body of the optical fiber array assembling apparatus, and the adhesive is cured off-line. Next, a separately prepared curing jig is placed on the main body of the optical fiber array assembling apparatus, and the next optical fiber array is assembled.

[0038]

According to the method of assembling the polarization-maintaining fiber array of the present invention, the thermosetting adhesive is applied to the lid having a flat surface, so that a uniform amount of liquid can be touched, and the groove for fixing the substrate can be formed. After the optical fiber is attached, the lid is temporarily held down, and the thermosetting adhesive is caused to flow so that there is no gap between the optical fiber, the optical fiber array substrate and the lid of the optical fiber array, and then the polarization is stored. Since the rotation of the surface is adjusted, the polarization preserving surface is accurately determined, and a smooth rotation state can be obtained by utilizing the lubricating effect of the thermosetting adhesive.

In the conventional method, it is necessary to lower the optical fiber in parallel with the groove of the substrate of the optical fiber array by using a proximity fiber holder. In many cases, the tip of the optical fiber is directly tweezers or the like. It is necessary to finely adjust the position of the optical fiber with respect to the groove, which requires skill of an operator. The method for aligning the optical fibers at a narrow pitch according to the present invention is that the tips can be aligned at a narrow pitch by simply sliding from the side along the guide groove or guide hole, not from above, and finally the fixing groove. Can be set reliably. Therefore, the use of the jig of the present invention eliminates the need for a skilled worker.

When measuring the polarization preserving surface, the incident light axis is not coincident with the optical path of the imaging side optical system, so that the incident light is incident on the light incident end face of a specific optical fiber of the optical fiber array arranged at a narrow pitch. It is possible to illuminate and not to apply the epi-illumination to the observation end face of the polarization-maintaining optical fiber. Therefore, it is possible to measure the polarization preserving surface in a state where the input side and output side optical fibers arranged side by side in the optical fiber array form a coil. As a result, after measuring the polarization preserving surface of the conventional input and output optical fibers independently, the man-hour was significantly reduced compared to the fusion of the input and output optical fibers. Connection loss can be eliminated.

The jig for rotating the polarization-maintaining optical fiber according to the present invention can rotate the fiber with a slight movement of the fiber. Can be arranged in a state close to parallel, and compact and accurate rotation adjustment can be performed.

Further, since the curing jig according to the present invention is formed separately from the apparatus main body, the curing of the thermosetting adhesive can be performed off-line, and the operation of the optical fiber array assembling apparatus can be performed. Rate can be improved. Therefore, the method for assembling an optical fiber array using the jig of the present invention was able to improve productivity. It is also an assembly method that is easy to automate.

[Brief description of the drawings]

FIG. 1 is a flow chart of the method of the present invention.

FIG. 2 is a plan view of an optical fiber guide groove and an optical fiber rotating mechanism according to the present invention.

FIG. 3 is a sectional view of an optical fiber guide hole according to the present invention.

FIG. 4 is a partial perspective view of an optical fiber guide groove according to the present invention.

FIG. 5 is a sectional view of a mounting portion of the optical fiber array substrate according to the present invention.

FIG. 6 is an explanatory diagram of a polarization plane measuring method for an optical fiber according to the present invention.

FIG. 7 is an explanatory diagram of a polarization plane measuring method for an optical fiber according to the present invention.

FIG. 8 is an explanatory diagram of a polarization plane measuring method for an optical fiber according to the present invention.

FIG. 9 (a) is a partial perspective view of a main part of a jig for rotating an optical fiber according to the present invention. (B) It is front sectional drawing of the principal part of the jig for rotating optical fibers according to this invention. (C) It is a side sectional view of the principal part of the principal part of the jig for rotating optical fibers according to the present invention.

FIG. 10A is a sectional view of a cam shaft of a jig for rotating an optical fiber according to the present invention. (B) It is a top view of the shape of the 3rd and 4th hole of the jig for rotating optical fibers according to this invention.

FIG. 11 is a cam diagram according to the present invention.

FIG. 12 is a sectional view of an example of a polarization-maintaining optical fiber.

FIG. 13 is an explanatory diagram of an example of a method for measuring the polarization maintaining surface of the polarization maintaining optical fiber.

FIG. 14 is a diagram illustrating a rotation adjustment method according to the related art.

[Explanation of symbols]

 Reference Signs List 1 optical fiber guide groove jig 2 optical fiber guide hole jig 3 optical fiber guide groove 4 optical fiber guide hole 5 wall between optical fiber guide grooves 7 vacuum suction hole 8 vacuum suction hole 9 vacuum suction hole 10 vacuum suction hole 12 curing Jig 15 Polarization preserving optical fiber 16 Optical fiber array 17 Optical fiber fixing groove 18 Optical fiber array substrate 21 Optical fiber 22 Objective lens 22a First lens 22b Second lens 23 Beam splitter 24 CCD camera 27 White light source 28 third hole 29 fourth hole 30 camshaft 31 first linear displacement cam 32 second linear displacement cam 33 eccentric cam 34 eccentric cam 35 upper sandwiching plate 37 lower sandwiching plate 38 coil spring 39 coil spring 40 Base 43 Push rod 45 Spring 82 Polarization preserving surface 83 Cladding 84 Core 86 Fiber rotating holder 9 Reference Signs List 1 light source 92 polarizer 94 analyzer 95 optical sensor 96 optical power meter

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) G02B 7/00 G02B 6/08

Claims (5)

(57) [Claims] 1. A substrate comprising a fixing groove for receiving and positioning an optical fiber, a polarization-maintaining optical fiber mounted in the fixing groove, and a lid for covering the optical fiber. In the method for assembling an optical fiber array, mounting the optical fiber in the fixing groove, disposing a thermosetting adhesive, placing the lid on the substrate on which the optical fiber is mounted, and placing the lid on the substrate By applying pressure to the lid, the thermosetting adhesive is caused to flow in the gap between the optical fiber, the substrate and the lid, and the pressure applied to the lid is released, and the polarization of the optical fiber is released. By measuring the storage surface and rotating the optical fiber, the polarization storage surface is adjusted to a predetermined angle, pressure is applied to the lid, and the thermosetting adhesive is cured in that state. Optical fiber array Assembly method. 2. A substrate comprising a fixing groove for accommodating and positioning an optical fiber, a polarization-maintaining optical fiber mounted in the fixing groove, and a lid for covering the optical fiber. In the method for assembling an optical fiber array, using an optical fiber guide mechanism, mounting the optical fiber in the fixing groove and applying a thermosetting adhesive to the back surface of the lid, Placed on the mounted substrate, and applying pressure to the lid placed on the substrate, causing the thermosetting adhesive to flow into the gap between the optical fiber, the substrate and the lid, The pressure applied to the optical fiber is released, the polarization maintaining surface of the optical fiber is measured, and the polarization maintaining surface is adjusted to a predetermined angle by rotating the optical fiber, and the pressure is applied to the lid, and the state is changed. With the heat Method of assembling an optical fiber array, characterized by curing the resistance adhesives. 3. An optical fiber guide groove having a groove width dimension at a front end slightly larger than a diameter of the optical fiber and a flat funnel shape having a wide rear end groove width. At least one vacuum suction hole for sucking the optical fiber with respect to a jig comprising: a jig, and the front end of the optical fiber is mounted from the wide end of the rear end of the optical fiber guide groove of the jig, 3. The method according to claim 2, wherein the tip of the optical fiber is advanced along the optical fiber guide groove while preventing the optical fiber from floating through the vacuum suction hole. 4. The optical fiber guide mechanism uses a jig provided with a funnel-shaped optical fiber guide hole having a hole diameter at the front end slightly larger than the diameter of the optical fiber and a large hole diameter at the rear end. 3. The method for assembling an optical fiber array according to claim 2, wherein the tip of the optical fiber is inserted from a funnel-shaped mouth at the rear end of the jig. 5. The pressure applied to the lid, a method of curing the thermosetting adhesive in that state, the claims using a portion for mounting a substrate of the optical fiber array separately jig Item 3. The method for assembling an optical fiber array according to Item 1 or 2.