JP3984136B2 - Optical fiber array and optical fiber array substrate - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an optical fiber array in which a plurality of optical fibers are positioned and integrated with an adhesive, and an optical fiber array substrate therefor.
[0002]
[Prior art]
The optical fiber array is used to connect a plurality of optical fibers to a planar optical waveguide (PLC) or to connect multi-core optical fibers by aligning and arranging a plurality of optical fibers in parallel at a predetermined pitch. FIG. 1 is a diagram showing an outline of a general optical fiber array. FIG. 1 (A) is a perspective view, and FIGS. 1 (B) and 1 (C) are partial sectional views of a1-a1. In the figure, 1 is an optical fiber array, 2 is an optical fiber, 2a is a fiber coating part, 3 is a substrate, 3a is a groove forming part, 3b is a flat part, 4 is a cover plate, 5 is a groove (V-shaped groove), 6 is an adhesive, 7 and 8 are gaps, and 9 is a stepped portion.
[0003]
As shown in FIG. 1A, the optical fiber array 1 is configured by holding and fixing a plurality of optical fibers 2 between a substrate 3 and a cover plate 4 in a parallel array at a predetermined arrangement pitch T.
The substrate 3 is formed such that the groove forming portion 3a and the flat portion 3b are stepped as shown by the step portion 9, and a plurality of grooves 5 for accommodating the optical fibers 2 are formed in parallel on the upper surface of the groove forming portion 3a. Has been. As shown in FIG. 1B, the groove 5 is generally formed in a V shape, and the optical fiber 2 has three points on both sides of the V-shaped groove 5 and the pressing surface of the cover plate 4. Positioned with. Further, in the case of an optical fiber array having a high density arrangement in which the arrangement pitch T of the optical fibers 2 is close to the outer diameter of the optical fiber 2, the optical fiber array is as shown in FIG.
[0004]
When the optical fiber array 1 is manufactured, the coating at the tip of the optical fiber 2 is removed to expose the bare glass fiber, and the optical fiber array 1 is accommodated in the groove 5 of the substrate 3 and is pressed and positioned by the lid plate 4 from above. . Thereafter, the adhesive 6 is injected from the front end side or the rear end side of the groove forming portion 3 a of the substrate 3. The adhesive 6 penetrates into the gap 7 generated between the optical fiber 2, the substrate 3, and the cover plate 4 and into the gap 8 generated between the optical fiber 2 and the groove 5 by capillary action. The optical fiber 2, the substrate 3, and the cover plate 4 are bonded and integrated.
[0005]
In the optical fiber 2, the exposed bare glass fiber is accommodated in the V-shaped groove 5, and the fiber coating portion 2 a on which the coating remains is placed on the flat portion 3 b of the substrate 3. After the optical fiber 2 is pressed by the cover plate 4 and bonded and fixed with the adhesive 6, the fiber coating portion 2a is bonded and fixed to the flat portion 3b with another adhesive (not shown) (for example, JP-A-2001-2001). 343547).
[0006]
[Problems to be solved by the invention]
In the optical fiber array 1 configured as described above, for example, it is assumed that the adhesive 6 is applied from the distal end side of the substrate 3 and is filled in the gaps 7 and 8 by capillary action. The adhesive 6 is used in two different gaps: a gap 7 generated between the optical fiber 2 and the upper surface of the substrate 3 and the lower surface of the cover plate 4, and a gap 8 generated between the optical fiber 2 and the groove 5 of the substrate 3. Infiltrated by capillary action. When the cross-sectional area S1 of the upper gap 7 is smaller than the cross-sectional area S2 of the lower gap 8, the speed at which the adhesive infiltrates in the upper gap 7 by capillary action is the adhesive in the lower gap 8 by capillary action. Is faster than the rate of penetration.
[0007]
FIG. 2 is a view showing an a2-a2 cross section of FIG. 1 (B) and showing an example in which the adhesive 6 is applied from the front end side of the substrate 3. As shown in FIG. 2B, if the cross-sectional area S1 of the upper gap 7 is smaller than the cross-sectional area S2 of the lower gap 8, the upper gap 7 is caused by the difference in the penetration speed of the adhesive 6 described above. The adhesive 6 that has entered inside reaches the outlet side at the rear end of the groove forming portion 3a earlier than the adhesive 6 that has entered the lower gap 8, and excess adhesive flows out from the outlet and hangs downward. .
[0008]
The adhesive hanging downwards closes the outlet side of the lower gap 8. If the outlet of the gap 8 is blocked before the adhesive 6 has sufficiently penetrated to the outlet side of the lower gap 8, bubbles P remain in the gap 8. If bubbles P remain in the gap 8, the adhesive force between the optical fiber 2 and the substrate 3 is reduced, and the substrate 3 is easily peeled off. Further, if the bubbles P remain in the gap 8, the bubbles P expand and change due to a temperature change, which causes bending or lateral pressure to the optical fiber 2 and increases transmission loss.
[0009]
The present invention has been made in view of the above-described circumstances, and an object thereof is to provide an optical fiber array in which bubbles are not generated in a gap portion filled with an adhesive and an optical fiber array substrate used therefor.
[0010]
[Means for Solving the Problems]
An optical fiber array according to the present invention comprises a substrate and a cover plate formed with a step between a groove forming portion and a flat portion, and a plurality of V-shaped openings whose side walls provided on the groove forming portion of the substrate have an opening angle. In this optical fiber array, optical fibers are accommodated and arranged in grooves, pressed by a cover plate and positioned, and a gap formed between the optical fiber, the substrate, and the cover plate is filled with an adhesive to be bonded and integrated.
Then, on the step side of the groove forming portion of the substrate, the opening angle of the V-shaped groove is gradually widened, or the depth of the V-shaped groove is gradually increased, and the height of the groove top portion is increased. The cross-sectional area of the gap portion that is gradually lowered and formed between the optical fiber and the upper surface of the substrate and the lower surface of the cover plate is S1, and the cross-sectional area of the gap portion that is formed between the groove of the substrate and the optical fiber is S2. In this case, S1> S2.
[0011]
A substrate for an optical fiber array according to the present invention is for forming the above-described optical fiber array, and a plurality of optical fibers are formed in a V-shape with both side walls provided at groove forming portions of the substrate having an opening angle. houses arranged Jo groove positioned presses with cover plate, Ru substrate der for an optical fiber array that integrally bonded by filling the adhesive in the gap portion generated between the optical fiber. The opening angle between both side walls of the V-shaped groove is preferably more than 70 ° and less than 100 ° .
[0012]
DETAILED DESCRIPTION OF THE INVENTION
The outline of the embodiment of the present invention will be described with reference to FIGS. 1 and 2. 1 and 2 are diagrams used for explaining the prior art, but since the shape itself is the same as the conventional one, it is used for explanation of the basic form of the present invention.
[0013]
As shown in FIG. 1A, an optical fiber array 1 according to the present invention has a plurality of optical fibers 2 arranged in parallel at a predetermined pitch between a substrate 3 and a cover plate 4 as described in the prior art. It is configured to be held and fixed to. The substrate 3 is formed in a shape in which the groove forming portion 3a and the flat portion 3b are stepped as shown by the step portion 9, and a plurality of grooves 5 for accommodating the optical fibers 2 are formed on the upper surface of the groove forming portion 3a. Has been. The optical fiber 2 is in a state in which the coating of the tip portion is removed to expose the bare glass fiber, and the optical fiber 2 is accommodated and arranged in the groove 5 of the groove forming portion 3a. Placed on.
[0014]
As shown in FIG. 1B, the groove 5 is formed in a V shape, for example, and both side walls of the groove 5 have an opening angle θ that is not parallel to each other. When the optical fiber 2 is stored in the groove 5, the optical fiber is positioned at a total of three points: two points in contact with both side walls of the groove having the opening angle θ and one point in contact with the pressing surface of the cover plate 4. It is. The cover plate 4 is lightly pressed to such an extent that the optical fiber can be positioned, and after being integrated by bonding, the pressing force is released. After the optical fiber 2 is pressed by the cover plate 4 and bonded and fixed with the adhesive 6, another adhesive (not shown) is applied to the flat portion 3b, and the fiber covering portion 2a is bonded and fixed.
[0015]
For the adhesive 6 that bonds the optical fiber 2, for example, an epoxy ultraviolet curing adhesive having a viscosity before curing of about 2.0 Pa · s is used. The substrate 3 and the cover plate 4 are made of glass (pyrex (registered trademark) glass, quartz glass, etc.) having a thermal expansion coefficient close to that of the optical fiber 2 or ceramic, and the grooving is formed by cutting or press molding. Is done.
[0016]
The optical fibers 2 are respectively housed and arranged in the grooves 5 of the substrate 3 and are positioned by being pressed by the cover plate 4 from above, and then the adhesive 6 is injected from the front end side or the rear side of the groove forming portion 3 a of the substrate 3. As shown in FIG. 1B, the adhesive 6 is generated in the gap 7 formed between the optical fiber 2 and the upper surface of the substrate 3 and the lower surface of the cover plate 4 and between the optical fiber 2 and the groove 5. The optical fiber 2, the substrate 3, and the cover plate 4 are bonded and integrated by filling the gap 8 by capillary action, filling the gaps 7 and 8.
[0017]
In the present invention, the cross-sectional area of the gap 7 formed between the optical fiber 2 positioned above during the bonding operation and the upper surface of the substrate 3 and the lower surface of the cover plate 4 is S1, and the optical fiber 2 positioned below during the bonding operation When the cross-sectional area of the gap 8 generated between the groove 5 is S2, the opening angle of the groove 5 and the distance between the substrate 3 and the cover plate 4 are set so that S1> S2.
[0018]
As shown in FIG. 2 (A), when the adhesive 6 is simultaneously injected into the gaps 7 and 8 from one side (left side in the figure), the adhesive 6 simultaneously passes through the gaps 7 and 8 by the capillary action. It enters toward the outlet side (the rear end portion of the groove forming portion 3a in the figure). By making the cross-sectional area S2 of the lower gap 8 smaller than the cross-sectional area S1 of the upper gap 7, the infiltration speed of the adhesive 6 is faster in the lower gap 8 having a smaller cross-sectional area than in the upper gap 7. Become. For this reason, after the lower gap 8 is completely filled with the adhesive 6, the upper gap 7 is similarly filled with the adhesive 6, and bubbles are not generated in the gap 8.
[0019]
2B, in FIG. 2B, the cross sectional area S2 of the lower gap 8 is larger than the cross sectional area S1 of the upper gap 7 as described in the section of the problem to be solved. Is the case. In this case, the penetration speed of the adhesive 6 is slower in the lower gap 8 having a larger cross-sectional area than in the upper gap 7. For this reason, before the inside of the lower gap 8 is completely filled with the adhesive 6, the upper gap 7 is filled with the adhesive 6, and the excess adhesive overflowing from the outlet of the gap 7 hangs downward and falls downward. The outlet of the gap 8 is blocked, and bubbles P are generated in the gap 8.
[0020]
The relative relationship between the cross-sectional area S1 of the gap 7 and the cross-sectional area S2 of the gap 8 varies depending on the outer diameter of the optical fiber 2, the arrangement pitch T of the fibers, the opening angle θ of both side walls of the groove 5, and the shape. If the outer diameter of the optical fiber 2 is constant assuming that a standardized outer diameter of 0.125 mm is used, the cross-sectional area S1 on the gap 7 side is relatively easy if the fiber arrangement pitch T is increased. Can be large. Further, by making the groove 5 V-shaped and increasing the opening angle θ of both side walls, the cross-sectional area S2 on the gap 8 side can be relatively easily reduced.
[0021]
However, the fiber arrangement pitch T is becoming smaller and more highly integrated, and can be formed at a pitch (0.127 mm) substantially equal to the glass outer diameter of the optical fiber 2. It is necessary to match this. If the opening angle θ of the groove 5 is too large, the positioning of the optical fiber 2 becomes unstable.
[0022]
As shown in FIG. 1 (C), the opening of the grooves in the high density array in which the optical fiber 2 has a glass outer diameter of 0.125 mm, the array pitch T is 0.127 mm, and the grooves 5 are V-shaped. It is the figure which calculated | required the relationship between angle (theta) and S2 / S1. From this figure, in order to satisfy S2 / S1 <1, the opening angle θ of the V-shaped groove 5 needs to exceed 70 °. Further, if the opening angle θ of the V-shaped groove 5 is empirically set to 100 ° or more, the optical fiber 2 is laterally displaced and the positioning becomes unstable. Therefore, from the viewpoint of positioning, it is necessary that S2 / S1> 0.3 and the opening angle θ be less than 100 °. Usually, in the above fiber arrangement, the opening angle θ of the V-shaped groove 5 is set to about 60 °.
[0023]
FIG. 4 is a diagram illustrating another example of the cross-sectional shape of the groove 5. Instead of making the cross-sectional shape of the groove 5 of the substrate 3 V-shaped as shown in FIG. 1, as shown in FIG. 4A, the V-shaped valley portion 5b is made into an inverted trapezoidal shape. Can do. However, it is assumed that the flat valley portion 5 b does not contact the optical fiber 2. This inverted trapezoidal groove can reduce the cross-sectional area S2 of the gap 8 formed between the optical fiber 2 and the groove 5 without impairing the fiber positioning function of the V-shaped groove. As a result, if the opening angle θ of the groove 5 is the same as that of the V-shaped groove, S2 / S1 can be further reduced. If S2 / S1 is the same as that of the V-shaped groove, the opening angle θ can be further reduced.
[0024]
Further, instead of making the cross-sectional shape of the groove 5 of the substrate 3 V-shaped as shown in FIG. 1, as shown in FIG. 4B, a U-shape having an arcuate V-shaped valley 5b. It can be. However, it is assumed that the arcuate valley portion 5b does not contact the optical fiber 2, and both side walls of the U-shaped groove have the same opening angle as that of the V-shaped groove. This U-shaped groove can reduce the cross-sectional area S2 of the gap 8 formed between the optical fiber 2 and the groove 5 without impairing the fiber positioning function of the V-shaped groove. As a result, if the opening angle θ of the groove 5 is the same as that of the V-shaped groove or the inverted trapezoidal groove, S2 / S1 can be further reduced. Further, if S2 / S1 is the same as that of the V-shaped groove or the inverted trapezoidal groove, the opening angle θ can be further reduced.
[0025]
5A and 5B are diagrams showing a substrate for an optical fiber array illustrating a preferred embodiment according to the present invention . FIG. 5A is a partial perspective view of the substrate, and FIG. 5B is an opening angle of a V-shaped groove. It is a figure which shows a change state. The reference numerals in the figure are the same as those used in FIG. 1 and FIG. FIG. 5 shows that the opening angle θ of the V-shaped groove 5 formed in the groove forming portion 3a of the substrate 3 is gradually increased on the stepped portion 9 side at the rear end of the groove forming portion 3a. This is an example in which the depth position of the valley portion 5b is constant from the upper surface of the groove forming portion 3a.
[0026]
When the arrangement pitch T of the optical fibers 2 is small and the top 5a has a sharp shape as shown in FIG. 5, as the opening angle θ of the V-shaped groove 5 gradually increases, the top 5a of the V-shaped groove 5 increases. The height gradually decreases, and a shallow V-shaped groove with a small difference from the valley 5b is obtained. However, when the arrangement pitch T of the optical fibers 2 is large and the top part 5a of the V-shaped groove 5 is flat, as shown by the change part 5e of the V-shaped groove 5 shown at the right end of FIG. The flat portion is gradually narrowed.
[0027]
As shown in FIG. 5A, the opening angle θ of the V-shaped groove 5 is, for example, gradually and gradually enlarged from the position after the longitudinal center of the V-shaped groove 5 toward the stepped portion 9 side. It is desirable to go. The optical fiber 2 is positioned at a linear portion where the opening angle θ ahead of the center position in the longitudinal direction of the V-shaped groove 5 is not changed.
[0028]
In the linear portion where the opening angle θ does not change, the opening angle of the V-shaped groove 5 is such that the cross-sectional area S1 of the gap 7 and the cross-sectional area S2 of the gap 8 described in FIG. The distance between the substrate 3 and the cover plate 4 is preferably set. When the optical fiber is formed with a high-density array pitch T as shown in FIG. 1C, the opening angle between both side walls of the V-shaped groove 5 in the linear portion exceeds 70 ° and is 100. It is preferable to be less than °.
[0029]
FIG. 5B is a diagram showing a change state of the groove cross section at the positions bb, cc, and dd in the longitudinal direction of the V-shaped groove 5 of FIG. The opening angle of the V-shaped groove 5 at the bb position is θ1, θ2 at the cc position, θ3 at the dd position, and θ1 <θ2 <θ3. If the depth position H of the valley portion 5b of the V-shaped groove 5 at each position in the longitudinal direction is constant from the upper surface line of the groove forming portion 3a, the height of the top portion 5a gradually decreases, and the difference from the valley portion 5b is It becomes a small shallow V-shaped groove.
[0030]
By forming the V-shaped groove 5 as described above, the gap between the V-shaped groove 5 and the cover plate 4 gradually increases on the stepped portion 9 side of the groove forming portion 3a. As a result, the cross-sectional area of the resin filling gap on the side of the stepped portion 9 is increased, and the adhesive can easily enter. Therefore, by allowing the adhesive to enter from the stepped portion 9 side toward the tip side of the substrate by capillary action, the adhesive can be smoothly filled in the gap without generating bubbles in the gap. Further, since the step portion 9 changes gently, stress concentration due to another adhesive (not shown) applied to the rear portion can be reduced, and an increase in loss can be prevented.
[0031]
Further, with the above configuration, the optical fiber 2 is gradually separated from contact with both side walls of the V-shaped groove 5 on the stepped portion 9 side of the groove forming portion 3a, and is in a floating state where it does not come into contact with the rear end edge 5c. As a result, the optical fiber 2 is not damaged at the step portion 9 of the groove forming portion 3a, and the occurrence of disconnection can be prevented.
[0032]
6A and 6B are diagrams showing another embodiment instead of FIG. 5, FIG. 6A is a partial perspective view of the substrate, and FIG. 6B is a diagram showing a change state of the depth of the V-shaped groove. . The reference numerals in the figure are the same as those used in FIG. 1 and FIG. In FIG. 6, the depth of the V-shaped groove 5 formed in the groove forming portion 3a of the substrate 3 is gradually increased on the stepped portion 9 side at the rear end of the groove forming portion 3a. In this example, the opening angle θ is constant.
[0033]
When the arrangement pitch T of the optical fibers 2 is small and the top 5a has a sharp shape as shown in FIG. 6, the height of the top 5a gradually decreases as the trough 5b of the V-shaped groove 5 becomes deeper. The relative height of the top 5a and the valley 5b is unchanged, and the cross-sectional area of the V-shaped groove 5 is also substantially constant. However, when the arrangement pitch T of the optical fibers 2 is large and the top part 5a of the V-shaped groove 5 is flat, as shown by the change part 5e of the V-shaped groove 5 shown at the right end of FIG. The flat portion is gradually narrowed.
[0034]
As shown in FIG. 6A, the valley portion 5b of the V-shaped groove 5 is smoothly and gradually deepened, for example, from the position after the longitudinal central portion of the V-shaped groove 5 toward the stepped portion 9 side. It is desirable to go. The positioning of the optical fiber 2 is performed at least in a linear portion where the depth of the valley portion 5b ahead of the center position in the longitudinal direction of the V-shaped groove 5 is not changed.
[0035]
In the linear portion where the opening angle θ does not change, the opening angle of the V-shaped groove 5 is such that the cross-sectional area S1 of the gap 7 and the cross-sectional area S2 of the gap 8 described in FIG. The distance between the substrate 3 and the cover plate 4 is preferably set. When the optical fiber is formed with a high-density array pitch T as shown in FIG. 1C, the opening angle between both side walls of the V-shaped groove 5 in the linear portion exceeds 70 ° and is 100. It is preferable to be less than °.
[0036]
FIG. 6B is a diagram showing a change in the depth of the groove at positions bb, cc, and dd in the longitudinal direction of the V-shaped groove 5 in FIG. 6A. The depth of the valley portion 5b of the V-shaped groove 5 at the bb position is H1 at the bb position, H2 at the cc position, H3 at the dd position, and H1 from the upper surface line of the groove forming portion 3a. <H2 <H3.
[0037]
By forming the V-shaped groove 5 as described above, the gap between the V-shaped groove 5 and the cover plate 4 is formed on the stepped portion 9 side of the groove forming portion 3a as in the example of FIG. Expand gradually. As a result, the cross-sectional area of the resin filling gap on the side of the stepped portion 9 is increased, and the adhesive can easily enter. Therefore, by allowing the adhesive to enter from the stepped portion 9 side toward the tip end side of the substrate by capillary action, the adhesive can be filled smoothly without generating bubbles in the gap. Moreover, since the step part 9 changes gently, the stress concentration with respect to other adhesives (not shown) applied to the rear part can be reduced, and an increase in loss can be prevented.
[0038]
Further, as in the example of FIG. 5, the optical fiber 2 is gradually separated from the contact with the both side walls of the V-shaped groove 5 on the stepped portion 9 side of the groove forming portion 3 a and is in contact with the rear end edge 5 c. Do not float. As a result, the optical fiber 2 is not damaged at the step portion 9 of the groove forming portion 3a, and the occurrence of disconnection can be prevented.
[0039]
The above-described substrate used for the optical fiber array according to the present invention is preferably formed by press molding using upper and lower molds. Since the V-shaped groove is not a straight and uniform shape in the longitudinal direction, machining by grinding is highly controlled and precise, and productivity is not good. However, in the case of press molding, since the mold only needs to be manufactured once, the cost of the mold increases somewhat, but the problem of productivity does not occur. In addition, the V-shaped groove formed by press molding has a uniform and smooth surface roughness compared to the ground one, so that the flow of adhesive into the gap is good and the optical fiber array has high reliability. Substrates and optical fiber arrays can be manufactured.
[0040]
【The invention's effect】
As is clear from the above description, according to the present invention, the gap formed between the optical fiber and the groove of the substrate can be filled with an adhesive without causing bubbles, and the substrate is peeled off. And an increase in loss can be prevented. Moreover, stress concentration and disconnection can be prevented by enlarging the gap on the step side of the groove forming portion.
[Brief description of the drawings]
FIG. 1 is a diagram for explaining the outline of an optical fiber array according to the present invention.
FIG. 2 is a diagram illustrating the flow of the adhesive when the adhesive is applied from the front end side of the substrate.
FIG. 3 is a diagram for explaining a relationship between an opening angle of a V-shaped groove of a substrate and a cross-sectional area of a gap.
FIG. 4 is a view showing another example of the groove shape of the substrate.
5 is a diagram showing the shape of a V-shaped groove of the substrate according to the present invention.
FIG. 6 is a view showing another shape of the V-shaped groove of the substrate according to the present invention .
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Optical fiber array, 2 ... Optical fiber, 2a ... Fiber coating | coated part, 3 ... Board | substrate, 3a ... Groove formation part, 3b ... Flat part, 4 ... Cover plate, 5 ... Groove (V-shaped groove), 5a ... Top part 5b ... trough part, 5c ... rear end edge, 5e ... change part, 6 ... adhesive, 7, 8 ... gap, 9 ... step part.

Claims (5)

An optical fiber is housed in a plurality of V-shaped grooves, each of which has an opening angle on both side walls provided in the groove forming portion of the substrate, which includes a substrate and a cover plate formed with a step between the groove forming portion and the flat portion. An optical fiber array that is aligned and pressed by the lid plate and is integrated by filling an adhesive into a gap portion formed between the optical fiber and the substrate and the lid plate,
On the step side of the groove forming portion of the substrate, the opening angle of the V-shaped groove is gradually widened and the height of the groove top portion is gradually lowered, and the optical fiber, the upper surface of the substrate, and the lower surface of the lid plate S1> S2, where S1 is the cross-sectional area of the gap formed between the substrate and the optical fiber, and S2 is the cross-sectional area of the gap formed between the groove of the substrate and the optical fiber. array. An optical fiber is housed in a plurality of V-shaped grooves, each of which has an opening angle on both side walls provided in the groove forming portion of the substrate, which includes a substrate and a cover plate formed with a step between the groove forming portion and the flat portion. An optical fiber array that is aligned and pressed by the lid plate and is integrated by filling an adhesive into a gap portion formed between the optical fiber and the substrate and the lid plate,
The depth of the V-shaped groove is gradually increased on the step side of the groove forming portion of the substrate, and the height of the groove top portion is gradually decreased. The optical fiber, the upper surface of the substrate, and the lower surface of the lid plate S1> S2, where S1 is the cross-sectional area of the gap formed between the substrate and the optical fiber, and S2 is the cross-sectional area of the gap formed between the groove of the substrate and the optical fiber. array.   The optical fiber array according to claim 1 or 2, wherein an outer diameter of the optical fiber is 125 µm, an arrangement pitch is 127 µm, and an opening angle between both side walls of the groove is more than 70 ° and less than 100 °. .   It uses for the optical fiber array of any one of Claims 1-3, The optical fiber array board | substrate characterized by the above-mentioned.   The optical fiber array substrate according to claim 4, wherein the optical fiber array substrate is formed by press molding.

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