WO2017179485A1

WO2017179485A1 - Connector member for optical waveguide, optical connector kit using same, and optical wiring obtained using optical connector kit

Info

Publication number: WO2017179485A1
Application number: PCT/JP2017/014361
Authority: WO
Inventors: 直人古根川; 雄一辻田
Original assignee: 日東電工株式会社
Priority date: 2016-04-12
Filing date: 2017-04-06
Publication date: 2017-10-19

Abstract

In order to provide a connector member for optical waveguide with which it is possible to suppress warpage and deformation of an optical waveguide and perform connection with minimal optical connection loss, and an optical connector kit using same, a connector member 1 for optical waveguide comprising a housing 6 having a placement part 3 on which an optical waveguide 2 is placed and a pair of walls 4 which rise from the placement part 3 with the optical waveguide 2 interposed therebetween, is characterized by a guide pin hole 5, into which a guide pin for positioning is inserted, being provided to each of the pair of walls 4, and the vertical distance B between the optical waveguide placement surface of the placement part 3 and the guide pin reference line L obtained by linking the centers of the guide pin holes 5 provided to the pair of walls 4 being set to satisfy the following formula (1). 0.018 mm ≤ B ≤ 0.045 mm (1)

Description

Optical waveguide connector member, optical connector kit using the same, and optical wiring obtained thereby

The present invention relates to an optical waveguide connector member used for optically connecting an optical waveguide and another light guide, an optical connector kit using the same, and an optical wiring obtained thereby.

In recent years, with the integration and enlargement of electronic devices, heat generation of electric wiring and power consumption that are frequently used to connect between boards in a device and between chips on the board have become problems. Therefore, an optical wiring (optical interconnection) technology has been developed in which these electric wirings are lightweight, have low heat generation, and use flexible optical waveguides and optical fibers.

In such an optical wiring, standardization of optical connectors used for connection between boards, etc. is progressing according to the shape, dimensions, test method JIS, etc., and the alignment connection method between optical connectors is also unified. Therefore, it can be easily connected to other connectors of different types (see, for example, Non-Patent Document 1).

For example, as shown in FIG. 9, a first optical connector in which a PMT ferrule (general-purpose ferrule for optical waveguide) 32 is attached to an end (termination) of an optical waveguide 31 and an end of a multi-core optical fiber 33 A second optical connector having an MT ferrule (general-purpose ferrule for optical fiber) 34 attached thereto, two guide pins 35 and guide pin holes 36 of each optical connector (not shown, but a pair of guides are also provided on the MT ferrule 34). By inserting each into the pin hole 36), the optical axes can be easily connected (optically coupled) with the optical axes positioned with high accuracy. In the present invention, the optical waveguide and the optical fiber are sometimes collectively referred to as a “light guide”.

When connecting two optical waveguides using an optical connector (optical coupling), it is necessary to make the optical connection loss as small as possible. For this reason, in an optical connector, a core or fiber of a light guide is usually positioned with reference to a pair of guide pin holes. When the light guide has a plurality of cores or fibers, each core on the connection surface Alternatively, the line obtained by connecting the centers in the fiber thickness direction is set to coincide with the line obtained by connecting the centers of the pair of guide pin holes (hereinafter referred to as “guide pin reference line”).

However, since an optical waveguide is usually a thin film, there is a problem that warpage is likely to occur compared to an optical fiber. When a warped optical waveguide is used for an optical connector, a line obtained by connecting the centers in the thickness direction of the cores on the connection surface does not become a straight line, and therefore cannot be matched with the guide pin reference line. When an optical connector using a warped optical waveguide is connected to another connector, the optical axes that should be aligned in the horizontal direction along the reference line are shifted, resulting in a great optical connection loss.

In order to solve such a problem, for example, in Patent Document 1, a warp correction member is provided in an optical connector, and the warp correction member is pushed down on a warped optical waveguide or by the pressure due to the weight of the warp correction member. It has been proposed to correct the warp of the optical waveguide.

Japanese Patent Laying-Open No. 2015-227958

However, as in Patent Document 1, when a warped optical waveguide is pressed by a warp correction member until the warp is eliminated, an excessive force is applied to the optical waveguide and deformed, and the optical axes are aligned. Connection (optical coupling) may not be possible. Further, when the warp correction member is pressed until the warp is eliminated, a force repelling the press is generated, so that there is a possibility that the optical connector is deformed with time and the durability is lowered.

The present invention has been made in view of such circumstances, and not only eliminates warping of the optical waveguide but also can suppress deformation of the optical waveguide and deformation of the optical connector over time. Provided are an optical waveguide connector member capable of making a small connection, an optical connector kit using the optical waveguide connector member, and an optical wiring obtained thereby.

The present invention is a connector member for an optical waveguide comprising a housing having a placement portion for placing an optical waveguide and a pair of wall portions rising from the placement portion with the optical waveguide interposed therebetween,
Guide pin holes into which positioning guide pins are inserted are respectively provided in the pair of wall portions, and a line obtained by connecting the centers of the guide pin holes provided in the pair of wall portions is a guide pin reference line L. In this case, the optical waveguide connector member in which the vertical distance B between the guide pin reference line L and the optical waveguide mounting surface of the above-described mounting portion is set to satisfy the following formula (1) is the first. The gist.
0.018 mm ≦ B ≦ 0.045 mm (1)

An optical connector kit comprising an optical waveguide having a core and a cladding, and the optical waveguide connector member of the first aspect,
The optical waveguide is in contact with the vertical thickness H of the core and the mounting portion when the vertical thickness of the core is H and the vertical thickness from the surface in contact with the mounting portion to the core is B ′. An optical connector kit in which the vertical thickness B ′ from the surface to the core is set to satisfy the following expression (2) is a second gist.
0.018 mm ≦ H / 2 + B ′ ≦ 0.045 mm (2)

In particular, in the optical connector kit of the second aspect, in the optical waveguide, the thickness H in the vertical direction of the core and the thickness B ′ in the vertical direction from the surface in contact with the mounting portion to the core are further described below. What is set to satisfy the expression (3) is a third gist.
0.12 mm <B ′ / (H / 2) <1.2 mm (3)

Of the optical connector kits according to the second and third aspects, in the optical waveguide connector member, the vertical distance from the bottom surface of the housing to the optical waveguide mounting surface is C, and the guide pins are provided from the bottom surface of the housing. When the vertical distance to the reference line L is D, the vertical thickness H of the core of the optical waveguide and the vertical thickness B ′ from the surface in contact with the mounting portion to the core are expressed by the following equation (4) ) Is the fourth gist.
D = H / 2 + B ′ + C (4)

An optical connector kit comprising an optical waveguide having a core and a clad, the optical waveguide connector member of the first aspect, and a sheet,
The sheet is disposed between the optical waveguide and the optical waveguide connector member,
When the thickness in the vertical direction of the core of the optical waveguide is H and the thickness in the vertical direction from the surface in contact with the sheet placement portion to the core is B ″, the thickness H in the core vertical direction and the sheet placement The fifth gist is that the thickness B ″ in the vertical direction from the surface in contact with the part to the core is set to satisfy the following formula (5).
0.018 mm ≦ H / 2 + B ″ ≦ 0.045 mm (5)

In the optical connector kit of the fifth aspect, the thickness H in the vertical direction of the core of the optical waveguide and the thickness B ″ in the vertical direction from the surface contacting the sheet mounting portion to the core are further described below. What is set to satisfy the formula (6) is defined as a sixth gist.
0.12 mm <B ″ / (H / 2) <1.2 mm (6)

Further, in the optical connector kit according to the fifth or sixth aspect, in the optical waveguide connector member, a vertical distance from the bottom surface of the housing to the optical waveguide mounting surface is C, and the guide pin extends from the bottom surface of the housing. When the vertical distance to the reference line L is D, the vertical thickness H of the core of the optical waveguide and the vertical thickness B ″ from the surface in contact with the sheet mounting portion to the core are expressed by the following equation: What has the relationship of (7) is made into the 7th summary.
D = H / 2 + B ″ + C (7)

Of the optical connector kits according to the second to seventh aspects, the optical waveguide further includes a functional layer, and the functional layer is provided on the side in contact with the mounting portion. .

Furthermore, an optical wiring comprising an optical waveguide and the optical waveguide connector member of the first aspect is a ninth aspect, and among the optical wirings of the ninth aspect, the front end surface of the housing of the optical waveguide connector member The tenth gist is that the distance E between the end surface of the end of the optical waveguide held by the mounting portion of the housing is set to 5 to 50 μm.

In order to realize a connection with a small optical connection loss, the present inventors have conducted intensive research focusing on the problem of eliminating the warpage of the optical waveguide in the optical connector using the optical waveguide. As a result, in an optical waveguide connector member used for an optical connector (hereinafter referred to as “connector member”), a line obtained by connecting the centers of a pair of guide pin holes provided in the connector member, and the optical waveguide mounting of the connector member It has been found that by setting the vertical distance from the mounting surface within a specific range, not only the warping of the optical waveguide can be eliminated, but also the deformation of the optical waveguide and the optical connector over time can be suppressed. It was.

In the present invention, “connection with small optical connection loss” means that the allowable value of optical connection loss is 1 dB or less.

That is, according to the present invention, the vertical distance B between the guide pin reference line L and the optical waveguide mounting surface of the mounting portion satisfies the above formula (1), and the film thickness is larger than that of the conventional product. Suitable for thin optical waveguides. For this reason, a large force is not required to eliminate the warp of the optical waveguide. Therefore, even when pressed by a lid or the like, the optical waveguide is not greatly deformed, and connection (optical coupling) in a state where the positional deviation of the optical axis is small is possible. Further, since the pressing force is small, the repulsive force is small and the deformation of the optical connector over time can be suppressed. Therefore, it is possible to provide a connector member capable of performing connection with low optical connection loss at low cost. In the present invention, “connection in a state where the positional deviation of the optical axis is small” means that the connection is made in a state where the positional deviation of the center of the optical axis of each light guide is 10 μm or less.

An optical connector kit comprising the connector member of the present invention and an optical waveguide having a core and a clad, wherein the optical waveguide has a thickness in the vertical direction of the core as H, and comes into contact with the mounting portion. When the thickness in the vertical direction to the core is B ′, the thickness H in the vertical direction of the core and the thickness B ′ in the vertical direction from the surface in contact with the mounting portion to the core satisfy the above formula (2). In addition to the effects obtained from the connector member of the present invention, the set item can reduce the variation in the thickness of the optical waveguide, so that an optical connector with a smaller optical connection loss can be obtained. In addition, since the thickness H in the vertical direction of the core of the optical waveguide and the thickness B ′ in the vertical direction from the surface in contact with the mounting portion to the core are designed to satisfy the above formula (2), a connector using a fiber is used. It is possible to obtain an optical connector that can be easily connected to the.

In particular, in the optical waveguide, an optical connector in which the thickness H in the vertical direction of the core and the thickness B ′ in the vertical direction from the surface in contact with the mounting portion to the core are further set to satisfy the above formula (3). Since the kit reduces stress due to the difference in linear expansion between the core and the clad, the occurrence of warpage is suppressed, and an optical connector with a smaller optical connection loss can be obtained. Moreover, since stress at the time of attaching the optical waveguide to the connector member is relieved, an optical connector in which deformation is suppressed can be obtained. Furthermore, in the optical waveguide, since the stress accompanying the environmental temperature change is reduced, it is possible to obtain an optical connector in which deformation with time is suppressed.

In the connector member, when the vertical distance from the bottom surface of the housing to the optical waveguide mounting surface is C and the vertical distance from the bottom surface of the housing to the guide pin reference line L is D, the core of the optical waveguide The optical connector kit in which the vertical thickness H and the vertical thickness B ′ from the surface in contact with the mounting portion to the core have the relationship of the above-described formula (4) includes an optical waveguide as a connector member and an adhesive layer. Even in the case of mounting via the optical connector, since the position control in the thickness direction of the core and the clad is easy, an optical connector with smaller optical connection loss can be obtained.

An optical waveguide kit comprising the optical waveguide connector member of the present invention, an optical waveguide having a core and a clad, and a sheet, wherein the sheet is disposed between the optical waveguide and the optical waveguide connector member. When the thickness in the vertical direction of the core of the optical waveguide is H and the thickness in the vertical direction from the surface in contact with the sheet placement portion to the core is B ″, the thickness H in the vertical direction of the core is In addition to the effect obtained from the connector member of the present invention, the thickness B ″ in the vertical direction from the surface in contact with the sheet placement portion to the core is set so as to satisfy the above formula (5). Since variations in the thickness of the waveguide are reduced, an optical connector with a smaller optical connection loss can be obtained. The optical waveguide core is designed such that the vertical thickness H of the core and the vertical thickness B ″ from the surface in contact with the sheet mounting portion to the core satisfy the above formula (5). It is possible to obtain an optical connector that can be easily connected to a connector, and to improve functions such as impact resistance, vibration resistance, flame retardancy, and adhesiveness depending on the properties of the sheet. it can.

In particular, the thickness H in the vertical direction of the core of the optical waveguide and the thickness B ″ in the vertical direction from the surface in contact with the sheet mounting portion to the core are set so as to further satisfy the above formula (6). Since the stress due to the difference in linear expansion between the core and the clad is reduced, the occurrence of warpage can be suppressed, and an optical connector with a smaller optical connection loss can be obtained. Since the stress at the time of mounting is relaxed, an optical connector in which deformation is suppressed can be obtained, and in addition, in the optical waveguide, the stress accompanying the change in environmental temperature is reduced, so that the light whose deformation with time is suppressed. A connector can be obtained.

In the optical waveguide connector member, when the vertical distance from the bottom surface of the housing to the optical waveguide mounting surface is C and the vertical distance from the bottom surface of the housing to the guide pin reference line L is D, The optical waveguide core has a thickness H in the vertical direction and a thickness B ″ in the vertical direction from the surface in contact with the sheet mounting portion to the core having the relationship of the above formula (7). Even when it is attached via an adhesive layer or the like, since the position control of the core and the clad in the thickness direction is easy, an optical connector with a smaller optical connection loss can be obtained.

When the optical waveguide further has a functional layer, and the functional layer is provided on the side in contact with the mounting portion, the optical waveguide itself has impact resistance, vibration resistance, flame resistance, adhesiveness, etc. A function can be imparted and an optical connector with even higher durability can be obtained.

Also, the optical wiring provided with the connection structure using the optical connector can provide a high-quality optical connection structure with low cost and low optical connection loss. In particular, the distance E between the distal end surface of the optical waveguide connector member and the distal end surface of the optical waveguide held by the mounting portion of the housing is set to 5 to 50 μm. In the connection structure, even if connection and disconnection with an optical connector holding another light guide path is repeated, the end face of the end of the optical waveguide is not damaged, so the optical connection loss is unlikely to increase and good for a long time Can be used for Further, the distance between the end face of the connection partner and the end portion of the optical waveguide held by the connector member is preferable because the influence on the optical connection loss is almost negligible.

It is a perspective view of the optical connector obtained using the optical connector kit which is one of the embodiments of the present invention. It is explanatory drawing of the said optical connector. It is explanatory drawing of the connector member used for the said optical connector. (A) It is a perspective view which shows the modification of the said connector member partially, (b) is the explanatory drawing. (A) is explanatory drawing which shows partially the modification of the clad of the optical waveguide used for the said optical connector, (b) And (c) is explanatory drawing which shows partially the modification of the said optical connector. . It is explanatory drawing of the optical wiring provided with the connection structure by the said optical connector. In the Example and comparative example of this invention, it is a figure explaining the method of evaluating an optical waveguide. In the Example and comparative example of this invention, it is a figure explaining the method of evaluating a connector member. It is explanatory drawing of the connection structure by a general optical connector.

Next, embodiments of the present invention will be described in detail. However, the present invention is not limited to this embodiment.

FIG. 1 shows an optical connector obtained by using the optical connector kit of the present invention, and FIG. 2 explains the configuration of the optical connector. An optical connector kit used for this optical connector includes a connector member 1 and an optical waveguide 2, and the connector member 1 includes a mounting portion 3 on which the optical waveguide 2 is mounted and an optical waveguide 2 from the mounting portion 3. A housing 6 having a pair of wall portions 4 that rises with a cover interposed therebetween, and a lid body 7 for contacting and fixing the optical waveguide 2 placed on the placement portion 3. 1 and 2, each part is schematically shown, and is different from the actual thickness, size, etc. (the same applies to the following drawings).

In the connector member 1, the pair of wall portions 4 of the housing 6 are used for connection with other optical connectors on the distal end surface 4 a on the side which is abutted against other optical connectors and used for connection, Guide pin holes 5 for inserting guide pins used for positioning when placing the waveguide 2 are provided, and these penetrate through from the distal end surface 4a to the proximal end surface 4b into which the end of the optical waveguide 2 enters. .

As shown in FIG. 3, the housing 6 of the connector member 1 is placed with the guide pin reference line L when the line obtained by connecting the centers of the guide pin holes 5 is the guide pin reference line L. The vertical distance B between the portion 3 and the mounting surface of the optical waveguide 2 satisfies the following formula (1). This is one of the major features of the present invention. In FIG. 3, in the connector member 1, a gap is provided between the housing 6 and the optical waveguide 2, but this gap is described for convenience in order to clearly distinguish each member from the actual one. Are different (the same applies to the following figures).
0.018 mm ≦ B ≦ 0.045 mm (1)

According to this connector member 1, the vertical distance B between the guide pin reference line L and the mounting surface of the optical waveguide 2 of the mounting part 3 is set to a predetermined range shorter than that of the conventional product. For this reason, the optical waveguide 2 having a smaller film thickness than that of the conventional product can be employed, and even if the optical waveguide 2 is warped, a large force is not required for eliminating the warp. Therefore, the pressure by the lid 7 is small, the optical waveguide 2 is not greatly deformed, and the repulsive force is also small, so that the deformation of the optical connector can be suppressed over a long period of time. Therefore, it is possible to provide an optical connector that is low in cost, excellent in durability, and capable of performing optical coupling in a state in which the optical axes are more aligned.

In particular, as the connector member 1, when the vertical distance from the bottom surface of the housing 6 to the optical waveguide mounting surface is C and the vertical distance from the bottom surface of the housing 6 to the guide pin reference line L is D, the light guide It is preferable that the vertical thickness H of the core 9 of the waveguide 2 and the vertical thickness B ′ from the surface in contact with the mounting portion 3 to the core 9 have the relationship of the following formula (4). When these have the relationship of formula (4), when the optical waveguide 2 is attached to the connector member 1 via an adhesive layer or the like to obtain an optical connector, the core 9 and the clad 10 regardless of the thickness of the adhesive layer or the like. Therefore, it is possible to obtain an optical connector with smaller optical connection loss. Further, it is preferable that the vertical distance C from the bottom surface of the housing 6 to the optical waveguide mounting surface is in a range of 1.205 mm or more and 1.232 mm or less because position control in the thickness direction becomes easier.
D = H / 2 + B ′ + C (4)

The housing 6 and the lid 7 used for such a connector member 1 are dark or black by adding a light-impermeable resin, or a light-transmitting resin and a coloring material such as a pigment or an expanding material such as titanium. The resin can be formed by transfer molding, mold molding, injection molding, or the like, using a resin that is light-impermeable.

On the other hand, an optical waveguide 2 used as an optical connector kit in combination with the connector member 1 includes, for example, a plurality of cores 9 and a clad 10 provided vertically so as to sandwich them as shown in FIG. (Underclad and overclad).

Such an optical waveguide 2 can be obtained by, for example, a method of laminating the clad 10 and the core 9 while sequentially patterning them using an ultraviolet curable resin such as an epoxy resin and photolithography using an exposure mask. it can. The optical signal incident on the core 9 is designed so that the refractive index (optical refractive index) of the core 9 is higher than the refractive index of the cladding 10 so that the optical signal is transmitted only through the core 9. Yes.

In particular, the optical waveguide 2 is set so that the vertical thickness H of the core 9 and the vertical thickness B ′ from the surface in contact with the mounting portion 3 to the core 9 satisfy the following formula (2). What is done is preferable. That is, if the thickness H in the vertical direction of the core 9 and the thickness B ′ in the vertical direction from the surface in contact with the mounting portion 3 to the core 9 satisfy the following formula (2), the thickness of the optical waveguide 2 is This is because the balance between the reduction in variation and the ease of connection with a connector using a fiber is excellent.
0.018 mm ≦ H / 2 + B ′ ≦ 0.045 mm (2)

The optical waveguide 2 is set so that the vertical thickness H of the core 9 and the vertical thickness B ′ from the surface in contact with the mounting portion 3 to the core 9 further satisfy the following expression (3). What is done is preferable. When the vertical thickness H of the core 9 and the vertical thickness B ′ from the surface in contact with the mounting portion 3 to the core 9 satisfy the following expression (3), the line between the core 9 and the clad 10 Since the stress due to the difference in expansion is reduced, the occurrence of warpage is suppressed, and the stress at the time of attachment to the connector member 1 is also alleviated, so that an optical connector in which deformation is suppressed can be obtained. Furthermore, in the optical waveguide 2, the stress accompanying the environmental temperature change is reduced, and the temporal deformation of the optical connector can be suppressed.
0.12 mm <B ′ / (H / 2) <1.2 mm (3)

The vertical thickness B ′ of the clad 10 is preferably 0.003 mm or more and 0.028 mm or less, and the vertical thickness H of the core 9 is 0.035 mm or more and 0.05 mm or less. Is preferred. When the thickness B ′ in the vertical direction of the clad 10 and the thickness H in the vertical direction of the core 9 are within the above ranges, respectively, the durability is excellent, and optical coupling is performed in a state where the optical axes of the clads 10 are more aligned. An optical connector that can be performed can be obtained.

The optical connector kit includes, as accessories of the connector member 1, a guide pin for insertion into the guide pin hole 5 and a boot portion 8 combined with the housing 6 through the optical waveguide 2. The configuration is the same as in the prior art, and illustration and description thereof are omitted. Some connector members have a boot portion integrally formed on the base end surface side of the housing. In that case, it is not necessary to combine the boot part as a separate member.

In the connector member 1 according to the above-described embodiment, the housing 6 includes a placement portion 3 and a pair of wall portions 4 that rise from the placement portion 3 with the optical waveguide 2 interposed therebetween, as shown in FIG. When viewed from the front end surface 4a direction, it is U-shaped, and its opening is closed by the lid 7, but as shown schematically in FIG. It may be cylindrical. In this case, the lid 7 is not necessary. Also in this case, as shown in FIG. 4B, the distance and thickness can be appropriately set.

Further, in the above embodiment, the clad 10 of the optical waveguide 2 includes an under clad and an over clad, but may further include a functional layer 11 as indicated by reference numeral 11 in FIG. . In this case, the thickness B ′ in the vertical direction from the surface contacting the mounting portion 3 of the optical waveguide 2 to the core 9 is a distance including the functional layer 11 as shown in FIG. According to this configuration, it is possible to improve the performance of the connector kit by appropriately designing the function to be imparted to the functional layer 11.

Examples of the functional layer 11 include a flame retardant layer, a high hardness layer, an antifouling layer, a slipperiness-imparting layer, an antistatic layer, a thickness adjusting layer, a smoothness-imparting layer, and an adhesive layer. The functional layer 11 may contain various additives. Examples of such additives include flame retardants, hard auto materials, long-chain aliphatic compounds, lubricants, conductive polymers, leveling agents, various fillers, plasticizers, mold release agents, and the like. These may be used alone or in combination of two or more. Further, the functional layer 11 may be a single layer or a multilayer. And the said functional layer 11 can be obtained by laminating | stacking the material composition which forms a functional layer on the side which touches the mounting part surface of the optical waveguide 2 by methods, such as coating, for example.

Moreover, in the said embodiment, although the optical waveguide 2 is directly mounted in the mounting part 3 of the connector member 1, even if the optical waveguide 2 and the mounting part 3 of the connector member 1 do not contact | connect directly. Good. For example, as illustrated in FIG. 5B, the optical waveguide 2 may be placed on the placement portion 3 of the connector member 1 via the sheet 12. In this case, when the thickness in the vertical direction of the core 9 of the optical waveguide 2 is H and the thickness in the vertical direction from the surface in contact with the placement portion 3 of the sheet 12 to the core 9 is B ″, the following formula (5 This configuration can not only achieve the same effect as the embodiment described above, but also by appropriately designing the thickness and function of the sheet 12. 5 (b), the sheet 12 is arranged with a gap between the housing 6 and the optical waveguide 2, but this gap is not shown in FIG. Each member is described for the sake of clarity and is different from the actual one (the same applies to the following drawings).
0.018 mm ≦ H / 2 + B ″ ≦ 0.045 mm (5)

The vertical thickness H of the core 9 of the optical waveguide 2 and the vertical thickness B ″ from the surface of the sheet 12 in contact with the placement portion 3 to the core 9 further satisfy the following formula (6). If set as above, since the stress due to the difference in linear expansion between the core 9 and the clad 10 is reduced as in the above embodiment, the occurrence of warpage is suppressed, and the stress when attaching to the connector member 1 Therefore, it is possible to obtain an optical connector in which deformation is suppressed, and in the optical waveguide 2, stress due to environmental temperature change is reduced, and deformation of the optical connector over time can be suppressed.
0.12 mm <B ″ / (H / 2) <1.2 mm (6)

Further, in the connector member 1, when the vertical distance from the bottom surface of the housing 6 to the optical waveguide mounting surface is C and the vertical distance from the bottom surface of the housing 6 to the guide pin reference line L is D, the light guide When the thickness H in the vertical direction of the core 9 of the waveguide 2 and the thickness B ″ in the vertical direction from the surface in contact with the placement portion 3 of the sheet 12 to the core 9 have the relationship of the following formula (7), 2 is attached to the connector member 1 via an adhesive layer or the like to obtain an optical connector, because the position control in the thickness direction of the core 9 and the clad 10 becomes easy regardless of the thickness of the adhesive layer or the like. An optical connector with a small optical connection loss can be obtained, and if the vertical distance C from the bottom surface of the housing 6 to the optical waveguide mounting surface is in the range of 1.205 mm or more and 1.232 mm or less, it is more in the thickness direction. Place Control is facilitated.
D = H / 2 + B ″ + C (7)

Examples of the sheet 12 include a sheet having the same function as the functional layer (flame retardancy, high hardness, antifouling property, slipperiness, antistatic, thickness adjustment, smoothness imparting, adhesiveness) and the like. can give. The sheet 12 may contain various additives, such as flame retardants, hard auto materials, long chain aliphatic compounds, lubricants, conductive polymers, leveling agents, various fillers, plasticizers, release agents, and the like. May be included. These may be used alone or in combination of two or more. Furthermore, the sheet 12 may be a single layer or a multilayer.

In the optical connector kit including the sheet 12, for example, before the optical waveguide 2 is placed on the housing 6 of the connector member 1, the sheet 12 is placed on the placement portion 3, and the optical waveguide 2 is placed on the sheet 12. It can be obtained by mounting the waveguide 2. The sheet 12 may be fixed to at least one of the surfaces of the housing 6 in contact with the mounting portion 3 and the mounting portion 3 of the clad 10, or may not be fixed to either. Examples of the method for fixing the sheet 12 include, but are not limited to, adhesion, adhesion, and fusion.

Further, as shown in FIG. 5C, when the optical waveguide 2 includes the functional layer 11, the optical waveguide 2 is naturally mounted on the mounting portion 3 of the housing 6 via the sheet 12. Also good. In this case, both of the advantages of providing the functional layer 11 and the sheet 12 are obtained.

Next, FIG. 6 shows an example of an optical wiring having a connection structure using the optical connector. FIG. 6 partially shows a state in which the end portion of the optical waveguide 2 is held in the housing 6, and the tip end surface 2 a of the end portion of the optical waveguide 2 held in the housing 6 is the optical waveguide connector member 1. The distance from the front end surface 4a of the housing 6 is a distance E.

According to the above optical wiring, it is possible to provide a high quality optical connection structure with low cost and low optical connection loss. In addition, since the end tip surface 2a of the optical waveguide 2 is inside from the front end surface 4a of the housing 6 of the optical waveguide connector member 1, the optical connector in which another light guide path is held in the optical connection structure. Even if connection and removal are repeated, the end surface 2a of the end portion of the optical waveguide 2 is not damaged. For this reason, the optical connection loss is unlikely to increase and can be used satisfactorily for a long time.

The distance E between the distal end surface 4a of the housing 6 of the optical waveguide connector member 1 and the end distal end surface 2a of the optical waveguide 2 held by the housing 6 is preferably set to 5 to 50 μm. More preferably, the thickness is set to 5 to 20 μm. That is, if the distance E is too large, the distance from the optical coupling partner increases and the optical connection loss increases, and the rate of increase may not be negligible, which is not preferable. Also, if the distance E is too small, if the optical fiber protrudes from the tip surface of the optical connector that is the connection partner, or if the tip surface itself of the counterpart optical connector is uneven, by these convex parts, The end surface 2a of the end portion of the optical waveguide 2 may be damaged, which is not preferable.

Next, examples of the present invention will be described together with comparative examples. However, the present invention is not limited to the following examples unless it exceeds the gist. In the present application, the description of “parts” means “parts by weight”.

[Formation material for underclad and overclad]
First, the following materials were prepared as optical waveguide forming materials.
Component a: 60 parts of epoxy resin (manufactured by Mitsubishi Chemical Corporation, jER1001).
Component b: 30 parts of epoxy resin (EHPE3150, manufactured by Daicel Corporation).
Component c: 10 parts of an epoxy resin (DICA, 4816, manufactured by DIC).
Component d: 0.5 part of photoacid generator (manufactured by Sun Apro, CPI-101A).
Ingredient e: 0.5 part of antioxidant (Kyodo Pharmaceutical Co., Ltd., Songnox1010).
Component f: 0.5 part of antioxidant (manufactured by Sanko Co., Ltd., HCA).
Component g: 50 parts of ethyl lactate (solvent).
By mixing these components ag, materials for forming the underclad and overclad were prepared.

[Core forming material]
Component h: 50 parts of an epoxy resin (manufactured by Nippon Steel Chemical Co., Ltd., YDCN-700-3).
Component i: 30 parts of epoxy resin (manufactured by Mitsubishi Chemical Corporation, jER1002).
Component j: 20 parts of an epoxy resin (Ogsol PG-100, manufactured by Osaka Gas Chemical Company).
Component k: 0.5 part of a photoacid generator (manufactured by Sun Apro, CPI-101A).
Component l: 0.5 part of an antioxidant (Songnox 1010, manufactured by Kyodo Yakuhin Co., Ltd.).
Component m: 0.125 part of antioxidant (manufactured by Sanko Co., Ltd., HCA).
Component n: 50 parts of ethyl lactate (solvent).
A core forming material was prepared by mixing these components h to n.

[Examples 1 to 10, Comparative Example 1]
<Preparation of connector member>
First, polyphenylene sulfide (PPS) resin was injection-molded into a predetermined mold to produce the housing 6, the lid body 7, and the boot portion 8 shown in FIG. At that time, the vertical distance B, the vertical distance C, and the vertical distance D of the housing 6 were measured as shown in Table 1 below. The vertical distances are as follows. The lids 7 are each formed to have a thickness that abuts against the upper surface of the optical waveguide 2 placed on the placement unit 3.
Vertical distance B: When a line obtained by connecting the centers of the guide pin holes 5 provided in the pair of wall portions 4 is a guide pin reference line L, the guide pin reference line L and the optical waveguide mounting of the mounting portion 3 The vertical distance to the face.
Vertical distance C: vertical distance from the bottom surface of the housing 6 to the optical waveguide mounting surface.
Vertical distance D: Vertical distance from the bottom surface of the housing 6 to the guide pin reference line L.

<Preparation of optical waveguide>
A polyimide film having a width of 3 mm and a thickness of 15 μm was prepared as an electric circuit board. Then, on each surface of the electric circuit board, the under-cladding, the core, and the over-cladding are formed by performing patterning by predetermined mask exposure using the respective forming materials, and are shown in Table 1 to be described later. The optical waveguide 2 schematically shown in FIG. 3 was produced (total length: 5 cm) so as to have dimensions (unit: mm). In the optical waveguide 2, the number of cores was 12, the core width was 40 μm, and the core pitch was 250 μm.

<Assembly of optical connector>
The optical waveguide 2 with the adhesive applied to the lower surface (the surface on the mounting portion side of the housing) was set at a predetermined position on the mounting portion 3 of the housing 6. And the cover body 7 was covered on it, the boot part 8 was inserted, and after applying and applying a torque, the adhesive agent was hardened and the whole was integrated, and the optical connector was produced. However, only in Example 3, an adhesive was also applied to the upper surface of the optical waveguide 2 and set on the mounting portion 3 of the housing 6.

For Examples 1 to 10 and Comparative Example 1 obtained in this way, the items shown in Table 1 below were evaluated, and the results are also shown in Table 1. The evaluation method for each evaluation item is as follows.

[Thickness variation]
Before assembling the optical connector, each optical waveguide 2 used in the optical connectors of Examples 1 to 10 and Comparative Example 1 is observed with a length measuring microscope (BF-3017D, manufactured by Mitutoyo Corporation) and is in contact with the housing 6. The thickness α (see FIG. 7) from the surface of the cladding 10 on the side to the surface of the core 9 was measured for all channels (all 12 cores). And the difference of the maximum value and the minimum value was calculated | required from the obtained measured value, and the dispersion | variation in the thickness of the optical waveguide 2 was evaluated by applying to the following parameter | index.
◎ (very good): 5 μm or less ○ (good): more than 5 μm and 7 μm or less △ (pass): more than 7 μm and 10 μm or less × (bad): more than 10 μm

[Warpage amount]
Before assembling the optical connector, each optical waveguide 2 used in the optical connectors of Examples 1 to 10 and Comparative Example 1 is observed with a length measuring microscope (BF-3017D, manufactured by Mitutoyo Corporation) and is in contact with the housing 6. when a line obtained by connecting both ends m ₀ on the side of the cladding 10 surface and the virtual line M, the shortest distance from the m ₁ that equally divides an imaginary line M until the cladding 10 surface of the side in contact with the housing 6 beta ( 7) was measured. Then, the amount of warpage of the optical waveguide 2 was evaluated by applying the obtained shortest distance β to the following index.
◎ (very good): 15 μm or less ○ (good): more than 15 μm and 30 μm or less △ (pass): more than 30 μm and 40 μm or less × (bad): more than 40 μm

[Core misalignment]
Each optical waveguide 2 used in the optical connectors of Examples 1 to 10 and Comparative Example 1 was observed using a length measuring microscope (manufactured by Mitutoyo Corporation, BF-3017D), and the centers of the pair of guide pin holes 5 were connected. The shortest distance γ (see FIG. 8) between the obtained guide pin reference line L and the thickness center point p of the core 9 was measured for all channels (all 12 cores). And the shift | offset | difference of the core 9 position was evaluated by applying the average of the obtained shortest distance (gamma) to the following parameter | index.
◎ (very good): 8 μm or less ○ (good): more than 8 μm to 12 μm or less △ (pass): more than 12 μm to 20 μm or less × (bad): more than 20 μm

[Housing deformation]
Each of the housings 6 of the optical connectors of Examples 1 to 10 and Comparative Example 1 was observed using a length measuring microscope (manufactured by Mitutoyo Corporation, BF-3017D). Contact) When the line obtained by connecting q ₀ is defined as a virtual line Q, the shortest distance δ (see FIG. 8) from the point q _{1 at} which the virtual line Q is equally divided to the surface of the housing 6 was measured. The deformation of the housing 6 was evaluated by applying the obtained shortest distance δ to the following index.
◎ (very good): 3 μm or less ○ (good): more than 3 μm and 5 μm or less × (bad): more than 5 μm

From the results of Table 1 above, in all of Examples 1 to 10, the thickness variation and the amount of warpage are suppressed in the optical waveguide 2, and the displacement of the core 9 and the deformation of the housing 6 are suppressed in the optical connector. You can see that In particular, Examples 4 to 8 obtained ◎ evaluations for three or more of the four evaluation items, and are found to be particularly excellent. On the other hand, Comparative Example 1 corresponds to a conventional general-purpose product, but it is evaluated as x for any evaluation item, and it can be seen that the optical connector has a large optical connection loss. Further, according to Examples 1 to 10, an optical connector in which the functional layer 11 is provided on the clad of the optical waveguide 2 and an optical connector in which the optical waveguide 2 is mounted on the mounting portion 3 of the connector member 1 through the sheet 12. In Example 1, the same evaluation as in Examples 1 to 10 was performed, but the same excellent results as in Examples 1 to 10 were obtained.

In the above embodiments, specific forms in the present invention have been described. However, the above embodiments are merely examples and are not construed as limiting. Various modifications apparent to those skilled in the art are contemplated to be within the scope of this invention.

The present invention can be used for an optical connector capable of making a connection with a small optical connection loss.

DESCRIPTION OF SYMBOLS 1 Connector member for optical waveguides 2 Optical waveguide 3 Mounting part 4 Wall part 5 Guide pin hole 6 Housing L Guide pin reference line B Vertical distance

Claims

An optical waveguide connector member comprising a housing having a placement portion for placing an optical waveguide and a pair of wall portions that rise from the placement portion with the optical waveguide interposed therebetween,
Guide pin holes into which positioning guide pins are inserted are respectively provided in the pair of wall portions, and a line obtained by connecting the centers of the guide pin holes provided in the pair of wall portions is a guide pin reference line L. The vertical distance B between the guide pin reference line L and the optical waveguide mounting surface of the mounting portion is set so as to satisfy the following formula (1): Element.
0.018 mm ≦ B ≦ 0.045 mm (1)
An optical connector kit comprising: an optical waveguide having a core and a clad; and the optical waveguide connector member according to claim 1,
The optical waveguide is in contact with the vertical thickness H of the core and the mounting portion when the vertical thickness of the core is H and the vertical thickness from the surface in contact with the mounting portion to the core is B ′. An optical connector kit characterized in that a vertical thickness B ′ from the surface to the core is set to satisfy the following formula (2):
0.018 mm ≦ H / 2 + B ′ ≦ 0.045 mm (2)
3. The optical waveguide according to claim 2, wherein the thickness H in the vertical direction of the core and the thickness B ′ in the vertical direction from the surface in contact with the mounting portion to the core are further set to satisfy the following expression (3). Optical connector kit.
0.12 mm <B ′ / (H / 2) <1.2 mm (3)
In the optical waveguide connector member, when the vertical distance from the bottom surface of the housing to the optical waveguide mounting surface is C and the vertical distance from the bottom surface of the housing to the guide pin reference line L is D, the optical waveguide The optical connector kit according to claim 2 or 3, wherein the thickness H in the vertical direction of the core and the thickness B 'in the vertical direction from the surface in contact with the mounting portion to the core have the relationship of the following formula (4).
D = H / 2 + B ′ + C (4)
An optical connector kit comprising: an optical waveguide having a core and a clad; the optical waveguide connector member according to claim 1; and a sheet,
The sheet is disposed between the optical waveguide and the optical waveguide connector member,
When the thickness in the vertical direction of the core of the optical waveguide is H and the thickness in the vertical direction from the surface in contact with the sheet placement portion to the core is B ″, the thickness H in the core vertical direction and the sheet placement An optical connector kit characterized in that a vertical thickness B ″ from a surface in contact with the part to the core is set so as to satisfy the following formula (5):
0.018 mm ≦ H / 2 + B ″ ≦ 0.045 mm (5)
The thickness H in the vertical direction of the core of the optical waveguide and the thickness B ″ in the vertical direction from the surface in contact with the sheet mounting portion to the core are set so as to satisfy the following expression (6): 5. The optical connector kit according to 5.
0.12 mm <B ″ / (H / 2) <1.2 mm (6)
In the optical waveguide connector member, when the vertical distance from the bottom surface of the housing to the optical waveguide mounting surface is C and the vertical distance from the bottom surface of the housing to the guide pin reference line L is D, the optical waveguide The optical connector kit according to claim 5 or 6, wherein the vertical thickness H of the core and the vertical thickness B "from the surface in contact with the sheet mounting portion to the core have the relationship of the following formula (7): .
D = H / 2 + B ″ + C (7)
The optical connector kit according to any one of claims 2 to 7, wherein the optical waveguide further has a functional layer, and the functional layer is provided on a side in contact with the mounting portion.
An optical wiring comprising an optical waveguide and the optical waveguide connector member according to claim 1.
10. The optical wiring according to claim 9, wherein the distance E between the distal end surface of the housing of the optical waveguide connector member and the distal end surface of the optical waveguide held by the mounting portion of the housing is set to 5 to 50 μm.