JP5723336B2 - Optical fiber connection member - Google Patents

Description

  The present invention relates to an optical fiber connecting member.

  When aligning and fixing an optical fiber with a waveguide-type optical element having an optical waveguide provided on a substrate such as a planar lightwave circuit (PLC), the bonding cross-sectional area is widened to increase the mechanical strength of the bonded portion. In addition, an optical fiber connecting member made of glass or the like is used. For example, there are a V-groove glass substrate (V-groove fiber block), a ferrule, and the like. An optical fiber is fixed to such an optical fiber connecting member, and the optical fiber connecting member is bonded to the waveguide type optical element.

  When a ferrule is used as the optical fiber connecting member, the size can be reduced. However, since the bonding surface between the jig for accurate manipulation of the ferrule and the ferrule is close, there is a possibility that the adhesive adheres to the jig. Therefore, it is difficult to use a small ferrule.

  Here, the “ferrule” refers to a columnar optical fiber connecting member that has a fine fine hole into which an optical fiber is inserted and can hold, position, and protect the optical fiber. For example, glass, metal, semiconductor, Although it can be made of ceramic, plastic or the like, the above-mentioned problems exist with respect to any ferrule.

Japanese Patent Publication No. 7-76802

  The present invention has been made in view of such problems, and an object thereof is to downsize an optical fiber connection member for connecting an optical fiber to a waveguide type optical element.

In order to achieve such an object, an embodiment of the present invention provides an optical fiber connection member for connecting an optical fiber to a waveguide type optical element, a holding portion for holding by a jig, and the holding portion. And a connection portion having a connection surface with a waveguide type optical element, and the connection portion is applied to the connection surface when connecting to the waveguide type optical element. The adhesive has a structure that prevents the adhesive from reaching the holding portion beyond the connecting portion.

More specifically, in the first aspect, and the holding portion and the connecting portion are ward minute Ri by the step, in any direction of the cross section of the position before Symbol step, the length of the connecting portion Is shorter than the length of the holding portion.

In the second aspect, the connection portion has a tapered structure in which a cross-sectional area continuously decreases from a boundary between the holding portion and the connection portion.

The third aspect of the present invention, and the holding portion and the connecting portion, characterized in that it divided into separate Ri by the groove.

The fourth aspect of the present invention is characterized in that the holding portion and the connection portion are separated by performing water repellent treatment on at least a part of the surface of the connection portion.

The fifth aspect of the present invention is characterized in that the length of the connecting portion is 500 μm or less.

  According to the present invention, in an optical fiber connecting member for connecting an optical fiber to a waveguide type optical element, a holding portion for holding by a jig, and a connecting portion separated from the holding portion, wherein A connecting portion having a connection surface with the waveguide type optical element, the adhesive applied to the connection surface when connecting to the waveguide type optical element reaches the holding portion beyond the connecting portion. By having a structure that suppresses this, the optical fiber connecting member can be reduced in size.

It is a figure which shows the optical fiber connection member which concerns on 1st Embodiment. It is a figure which shows the optical fiber connection member which concerns on 2nd Embodiment. It is a figure which shows the optical fiber connection member which concerns on 3rd Embodiment. It is a figure which shows the modification of 3rd Embodiment. It is a figure which shows the optical fiber connection member which concerns on 4th Embodiment. It is a figure which shows the modification 1 of 4th Embodiment. It is a figure which shows the modification 2 of 4th Embodiment. It is a figure which shows the modification 3 of 4th Embodiment.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. Each embodiment will be described separately, but these embodiments may be combined.

(First embodiment)
FIG. 1 shows an optical fiber connecting member according to the first embodiment. The optical fiber 10 is fixed to the optical fiber connection member 100, and the optical fiber connection member 100 and the waveguide type optical element 20 are connected by the adhesive 30. The optical fiber connecting member 100 includes a holding portion 101 held by the jig 40 and a connecting portion 103 divided by the holding portion 101 and a step 102. In the waveguide type optical element 20, an optical waveguide 22 is formed on a substrate 21, and a glass block (Yato) 23 is provided thereon.

  The adhesive 30 applied in the vicinity of the connection surface 103 </ b> A of the connection portion 103 with the waveguide type optical element 20 extends toward the jig 40 on the surface of the connection portion 103. 101 is not reached. In this way, by separating the connecting portion 103 where the adhesive 30 extends from the holding portion 101 by the step 102, the length of the connecting portion 103 is shortened so that the jig 40 is brought close to the connecting surface 103A. The adhesion of the agent 30 to the jig 40 can be suppressed. Therefore, the optical fiber connection member 100 can be reduced in size.

  When the optical fiber connecting member 100 is a ferrule having a circular cross section, the diameter of the connecting portion 103 is shorter than the diameter of the holding portion 101. Regardless of the cross-sectional shape, the same effect can be obtained if the length of the connecting portion 103 is shorter than the length of the holding portion 101 in any direction of the cross section at the level of the step 102.

(Second Embodiment)
FIG. 2 shows an optical fiber connecting member according to the second embodiment. The optical fiber connection member 200 includes a holding part 201 that is held by the jig 40 and a connection part 203 that is separated from the holding part 201. The connecting portion 203 is not divided by the step 102 as in the first embodiment, but has a cross-sectional area that continuously decreases from the boundary 202 between the holding portion 201 and the connecting portion 203. It can be said that it is tapered toward the connection surface 203A of the connection portion 203.

  The adhesive 30 applied in the vicinity of the connection surface 203 </ b> A extends toward the jig 40 on the surface of the connection portion 203, but does not reach the holding portion 201 due to the presence of the boundary 202. As described above, the connecting portion 203 where the adhesive 30 extends is separated from the holding portion 201 by the boundary 202, so that the length of the connecting portion 203 can be shortened to bring the jig 40 close to the connecting surface. The adhesion of 30 to the jig 40 can be suppressed. Therefore, the optical fiber connection member 200 can be reduced in size.

(Third embodiment)
FIG. 3 shows an optical fiber connecting member according to the third embodiment. The optical fiber connection member 300 includes a holding portion 301 that is held by the jig 40, and a connection portion 303 that is partitioned by the holding portion 301 and the groove 302.

  The adhesive 30 applied in the vicinity of the connection surface between the optical fiber connection member 300 and the waveguide optical element 20 extends toward the jig 40 on the surface of the connection portion 303, but is retained by the presence of the groove 302. It does not reach the part 301. In this way, by separating the connecting portion 303 where the applied adhesive 30 extends from the holding portion 301 by the groove 302, the length of the connecting portion 303 is shortened, and the jig 40 is connected to the connecting surface of the connecting portion 303. Adhesion of the adhesive 30 to the jig 40 can be suppressed even in the vicinity of 303A. Therefore, the optical fiber connection member 300 can be reduced in size.

  FIG. 4 shows a modification of the third embodiment. The groove 312 provided in the optical fiber connecting member 310 is formed over the holding portion and also functions as the holding portion. The adhesive 30 applied in the vicinity of the connection surface between the optical fiber connection member 310 and the waveguide type optical element 20 extends toward the jig 40 on the surface of the connection portion 311, but is retained by the presence of the groove 312. It does not reach the department.

(Fourth embodiment)
FIG. 5 shows an optical fiber connecting member according to the fourth embodiment. The optical fiber connecting member 400 includes a holding portion 401 held by the jig 40 and a connecting portion 403 whose surface is subjected to water repellent treatment. The holding portion 401 and the connecting portion 403 are divided by the boundary between the portion that has been subjected to the water repellent treatment and the portion that has not been subjected to the water repellent treatment.

  The adhesive 30 applied in the vicinity of the connection surface 403A between the connection portion 403 and the waveguide type optical element 20 does not reach the holding portion 401 because the surface of the connection portion 403 has been subjected to water repellent treatment. Even if the length is reduced and the jig 40 is brought close to the connection surface 403A, adhesion of the adhesive 30 to the jig 40 can be suppressed. Therefore, the optical fiber connection member 400 can be reduced in size.

  FIG. 6 shows a first modification of the fourth embodiment. As long as the water repellent treatment is applied to the connecting portion 403, the holding portion 401 may be treated like the optical fiber connecting member 410. In the case where the optical fiber connecting member 410 is a member such as a ferrule that is used by cutting a long member into a desired length, it can be produced by performing a cutting process after performing a water-repellent treatment on the whole in advance, Manufacturing costs can be reduced.

  FIG. 7 shows a second modification of the fourth embodiment. The water-repellent treatment area does not need to be the entire connection portion 403, and may be processed only in a partial area near the fixing jig 40 like the optical fiber connection member 420.

  FIG. 8 shows a third modification of the fourth embodiment. As in the optical fiber connection member 430, only a part of the connection portion 403 may be subjected to water repellent treatment. In the case of the modification 2 and the modification 3, since the area | region where the adhesive agent is applied increases, the effect of raising the adhesive strength can be expected.

  For the water repellent treatment, the wettability of the connection surface 403A needs to be smaller than the wettability of the connection part 403. For example, there are treatment methods such as coating of a polymer such as paint, fluorination treatment, and silicone oil coating, but the type of treatment is not limited. Further, the water repellent treatment may be continued for a period of time from application of the adhesive to curing, and it is not necessary to maintain sufficient water repellency until after the adhesive is cured.

(Other)
Although the four embodiments have been described above, the effect is higher as the length of the connecting portion in the optical axis direction is longer, but it is required to be short in terms of downsizing the fiber component. In the case of the viscosity (200 cP to 10000 cP) of a general adhesive for connection, a sufficient suppression effect can be obtained at 50 μm or more and 500 μm or less. The length of the ferrule depends on the size of the fixing jig. If the ferrule is a general optical glass (soda glass, borosilicate glass, quartz glass, etc.) or ceramic (zirconia, etc.), it is about 500 μm. If there is a holding part, sufficient holding is possible. Therefore, the length of the entire ferrule in the optical axis direction can be realized with 1 mm or less, and the size can be made extremely small as compared with the length (up to several mm) of a normal optical connection part.

DESCRIPTION OF SYMBOLS 10 Optical fiber 20 Waveguide type | mold optical element 21 Substrate 22 Optical waveguide 23 Glass block 100, 200, 300, 310, 400 Optical fiber connection member 101, 201, 301, 401 Holding part 102 Step 202 Boundary 302, 312 Groove 103, 203 , 303, 403 Connection part 103A, 203A, 303A, 403A Connection surface

Claims (5)

In an optical fiber connecting member for connecting an optical fiber to a waveguide type optical element,
A holding part for holding by a jig;
A connection section that is separated from the holding section, and includes a connection section having a connection surface with a waveguide-type optical element ;
And the holding portion and the connecting portion is divided into separate Ri by the step, in any direction of the cross section of the position before Symbol step, the length of the connecting portion is shorter than the length of the holding portion, the the adhesive applied to the connection surfaces, the optical fiber connecting member you characterized by suppressing from reaching to the holding part beyond the connecting portion of the connection with the waveguide type optical device. In an optical fiber connecting member for connecting an optical fiber to a waveguide type optical element,
A holding part for holding by a jig;
A connection section that is separated from the holding section, and includes a connection section having a connection surface with a waveguide-type optical element ;
The connecting portion is separated from the holding portion by having a tapered structure in which a cross-sectional area continuously decreases from the boundary between the holding portion and the connecting portion, and when connecting to the waveguide optical element, adhesive applied to the connection surfaces, the optical fiber connecting member you characterized by suppressing from reaching to the holding part beyond the connecting portion. In an optical fiber connecting member for connecting an optical fiber to a waveguide type optical element,
A holding part for holding by a jig;
A connection section that is separated from the holding section, and includes a connection section having a connection surface with a waveguide-type optical element ;
Wherein the holding portion and the connecting portion is ward Ri by the groove min, adhesive applied to the connection surface of the connection with the waveguide type optical device, the holding beyond the connecting portion optical fiber connecting member characterized in that restrain the span part. In an optical fiber connecting member for connecting an optical fiber to a waveguide type optical element,
A holding part for holding by a jig;
A connection section that is separated from the holding section, and includes a connection section having a connection surface with a waveguide-type optical element ;
The holding part and the connection part are separated by applying water-repellent treatment to at least a part of the surface of the connection part, and are applied to the connection surface when connecting to the waveguide type optical element. adhesive, the optical fiber connecting member you characterized by suppressing from reaching to the holding part beyond the connecting portion. The length of the said connection part is 500 micrometers or less, The optical fiber connection member in any one of Claim 1 thru | or 4 characterized by the above-mentioned.

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