JP2008197341A - Optical substrate, its manufacturing method, optical component having optical substrate, and electronic equipment having optical substrate - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical substrate in which damage is not liable to occur even in physical connection, and to provide a manufacturing method of the substrate. <P>SOLUTION: The optical substrate 50 is provided with a substrate body 52 and optical wiring 11 (optical waveguide core) imbedded in the substrate body 52. An incident/existing end face 12, situated at the end of the optical wiring 11, faces the end face 54 of the substrate body 52. The incident/exiting end face 12 is deflected inside the substrate body 52 from the end face 54 thereof. A recessed part 56 is provided in the end face 54 of the substrate body 52, while the incident/exiting end face 12 constitutes the bottom face of the recessed part 56. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an optical substrate having at least one layer of optical wiring, a manufacturing method thereof, an optical component including the optical substrate, and an electronic device including the optical substrate.

When optically connecting optical components and optical fibers, the optical waveguides of optical components and optical fibers are fixed to an appropriate connector ferrule, and the ferrules are butted in series to perform physical contact bonding (physical contact). Is known (see Patent Document 1).
JP 2006-284821 A

  Even when an optical substrate (polymer optical waveguide) made of a polymer material is connected to a quartz optical fiber, optical signals are transmitted by fixing the ferrules to each other and physically connecting the ferrules. .

However, quartz optical fibers have a significantly higher hardness than polymer optical waveguides.
Therefore, as shown in FIG. 27, there is a problem that the end face 6 is damaged by physical contact bonding between the end face 6 of the optical wiring 4 (optical waveguide core) provided on the optical substrate 2 and the quartz optical fiber 8.

  If the end face 6 of the optical wiring 4 is damaged, the connection characteristic of the optical signal is deteriorated and the optical signal cannot be transmitted. Or, there is a problem that long-term reliability in an environmental resistance test or the like is impaired.

The present invention has been made in view of the drawbacks of the prior art, and an object of the present invention is to provide an optical substrate that is less likely to be damaged even in physical connection and a method for manufacturing the same.
It is another object of the present invention to provide an optical substrate that can control the structure of the optical connection portion of the optical substrate and reduce connection loss with an optical fiber and the like, and a method for manufacturing the same.
It is another object of the present invention to provide an optical substrate with high reliability and good connection characteristics and a method for manufacturing the same.
Moreover, it aims at providing an optical component and an electronic device provided with such an optical substrate.

In order to achieve the above-mentioned object, the invention according to claim 1 includes a substrate body and an optical waveguide core embedded in the substrate body, and an incident / exit end face located at an end of the optical waveguide core is the substrate. An optical substrate facing an end surface of the main body, wherein the incident / exit end surface is offset to the inside of the substrate main body with respect to the end surface of the substrate main body.
The invention according to claim 2 is characterized in that a concave portion is provided on an end surface of the substrate body, and the incident / exit end surface constitutes a bottom surface of the concave portion.
The invention according to claim 3 is characterized in that the concave portion is formed in a funnel shape in which a cross-sectional area gradually increases from the incident / exit end surface toward the end surface of the substrate body.
The invention according to claim 4 is characterized in that both the substrate body and the optical waveguide core are made of synthetic resin.
The invention according to claim 5 is characterized in that the concave portion is filled with a refractive index matching agent.
The invention according to claim 6 is characterized in that a plurality of the optical waveguide cores are provided.
According to a seventh aspect of the present invention, a recess is provided on an end surface of the substrate body, the incident / exit end surface constitutes a bottom surface of the recess, and a distance between the end surface of the substrate body and the incident / exit end surface is 10 It is ˜500 μm.
The invention according to claim 8 is a method of manufacturing an optical substrate, wherein a linear optical waveguide core is cut into a predetermined length and a mold having a cavity corresponding to the optical substrate to be manufactured is provided. Hollow pipes having dimensions longer than the thickness of the molds are inserted in advance at locations corresponding to both end faces of the optical substrate, and both ends in the longitudinal direction of the cut optical waveguide core are inserted into the hollow pipe. The molten synthetic resin for molding the optical body of the optical substrate is poured into the cavity, and when the synthetic resin is cured, the hollow pipe is removed from the mold and the optical substrate is taken out from the cavity. It is characterized by doing so.
Further, in the invention according to claim 9, when the hollow pipe is removed from the mold, a concave portion is formed on the end face of the optical substrate by the removed hollow pipe, and the incident / exit end face of the optical waveguide core is: A bottom surface of the recess is formed, and the recess is filled with a refractive index matching agent.
According to a tenth aspect of the present invention, the optical substrate to be manufactured has a plurality of optical waveguide cores, and the optical substrate corresponds to the plurality of optical waveguide cores at locations corresponding to both end faces of the optical substrate of the mold. And a hollow pipe is inserted through each.
An eleventh aspect of the invention is an optical component comprising the optical substrate according to any one of the first to seventh aspects.
A twelfth aspect of the invention is an electronic apparatus comprising the optical substrate according to any one of the first to seventh aspects.

  By displacing the input / output end face of the optical waveguide core to the inside of the substrate body from the end face of the substrate body, it is possible to prevent the input / output end face of the optical waveguide core from being destroyed during physical connection with a quartz optical fiber or the like. . This has the effect of improving long-term reliability when the connector is connected.

Next, embodiments of an optical substrate and a method for manufacturing the same according to the present invention will be described with reference to the drawings.
FIG. 1 is a plan view of an optical substrate 50 of the present embodiment.
The optical substrate 50 includes a substrate body 52 and an optical wiring 11 (optical waveguide core) embedded in the substrate body 52.
The incident / exit end face 12 located at the end of the optical wiring 11 faces the end face 54 of the substrate body 52.
The incident / exit end face 12 is offset from the end face 54 of the substrate body 52 to the inside of the substrate body 52.
A concave portion 56 is provided on the end surface 54 of the substrate body 52, and the incident / exit end surface 12 constitutes the bottom surface of the concave portion 56.

The manufacturing method of the optical substrate 50 includes the following steps.
As shown in FIG. 2, a process of obtaining a cut optical wiring 11 by cutting a previously formed linear optical wiring 10 (optical waveguide core) into a predetermined length.
Next, as shown in FIG. 3, the molds at those positions are formed on the side walls of the mold 20, which are positions corresponding to both end faces of the optical substrate of the mold 20 having the cavity 20 </ b> A having a shape corresponding to the optical substrate to be manufactured. A step of inserting a hollow pipe 30 having a dimension longer than the thickness of 20 in advance and inserting both ends of the cut optical wiring 10 in the longitudinal direction into the hollow pipe 30 as shown in FIG.
Next, as shown in FIG. 5, a process of pouring and filling molten optical waveguide material 40 (cladding material), that is, molten synthetic resin for molding the optical substrate 50 into the cavity 20A.
Next, as shown in FIG. 6, a step of removing the hollow pipe 30 from the mold 20 when the optical waveguide material 40 is cured.
At this time, when the hollow pipe 30 is removed from the mold 20, the removed hollow pipe 30 forms a recess 56 in the end surface 54 of the optical substrate 50, and the incident / exit end surface 12 of the optical wiring 11 constitutes the bottom surface of the recess 56. is doing.
Next, as shown in FIG. 7, a step of taking out the optical substrate 50 from the cavity 20A.

For the optical wiring 10 and the optical waveguide material 40, a generally used polymer material (synthetic resin material) can be used.
Specifically, a carbonate material, an epoxy material, an acrylic material, an imide material, a urethane material, a silicone material, an organic material mixed with an inorganic filler, and the like can be used. However, the material is not limited thereto. However, it is desirable to use an optical material with a controlled refractive index.

  The optical wiring 10 can be formed in a linear shape by a discharge method using a dispenser or the like, a molding method, a direct exposure method, or the like.

Arbitrary organic materials and inorganic materials can be used for the mold 20 and the hollow pipe 30.
Specifically, acrylic materials, silicone materials, silicon wafers, metal materials, glass materials, and the like can be used, but are not limited thereto. In order to improve the mold release / peelability, a mold release / release layer may be provided on the surfaces of the mold 20 and the hollow pipe 30.

  The hollow pipe 30 can take any shape in accordance with the cross-sectional shape of the optical wiring 11. The cross-sectional shape of the hollow pipe 30 is, for example, a circular cross-section shown in FIG. Although the square cross section shown etc. are mentioned, it is not limited to these circular cross sections and square cross sections.

By fixing the optical wiring 11 at an arbitrary location in the hollow pipe 30, the distance from the end face 54 of the optical substrate 50 to the incident / exit end face 12 of the optical wiring 11 can be controlled as shown in FIG.
As shown in FIG. 1, the distance from the end surface 54 of the optical substrate 50 to the incident / exit end surface 12 of the optical wiring 11 is such that when the optical substrate 50 and the optical fiber 2 are connected, the light is incident on the incident / exit end surface 12 of the optical wiring 11. The dimensions are such that the fiber 60 does not come into contact.
If the distance from the end face 54 of the optical substrate 50 to the incident / exit end face 12 of the optical wiring 11 is too long, the optical connection characteristics deteriorate, so this distance is preferably about 10 to 500 μm.

By installing the hollow pipe 30 at an arbitrary position of the mold 20, the wiring pattern of the optical wiring 11 can be controlled.
By increasing the installation interval of the hollow pipe 30, a pitch conversion wiring or the like can be formed.

Moreover, by making the hollow pipe 30 into an arbitrary shape, the shape of the concave portion 56 of the optical substrate 50 (the concave shape of the end surface 54 of the optical substrate 50) can be controlled.
For example, as shown in FIG. 8, by using a funnel-shaped hollow pipe 31, an optical substrate 50 having a funnel-shaped depression can be formed as shown in FIG.
In other words, the concave portion 56 is formed in a funnel shape in which the cross-sectional area gradually increases from the incident / exit end surface 12 toward the end surface 54 of the substrate body 52.
Accordingly, as shown in FIG. 9, when the optical substrate 50 and the optical fiber 60 are connected, a self-alignment function can be provided in which the mutual positions automatically match.
Further, the optical aperture can be converted to an arbitrary size, which is advantageous in improving the connection characteristics between the optical fiber 60 and the optical wiring 11.

Further, as shown in FIG. 10, the refractive index difference between the optical wiring 11 and the optical fiber 60 can be matched by filling the concave portion 56 of the optical substrate 50 with the refractive index matching agent 70. The optical connection characteristics are improved.
Arbitrary organic materials and inorganic materials can be used for the refractive index matching agent 70. Specifically, an acrylic material, a silicone material, a glass material, or the like can be used, but is not limited thereto.

  The present invention will be described below with reference to examples, but the present invention should not be construed as being limited thereto. In the following description, the optical wiring of the optical substrate is described as one layer, but it is not always necessary to be one layer. In the following description, the optical wiring is described as multi-mode, but it is not always necessary to be in multi-mode.

(Example 1)
Example 1 will be described.
First, as shown in FIG. 11, an optical wiring 10 was formed by applying a core material 90 (NTT-AT UV curable epoxy optical waveguide material) on a core mold 80 and irradiating with UV.

  Next, as shown in FIG. 12, the optical wiring 10 was cut | disconnected by arbitrary length, and the optical wiring 11 was created.

  Next, as shown in FIG. 13, the optical wiring 11 was inserted into the hollow pipe 30 installed on the side surface of the mold 20.

  Next, as shown in FIG. 14, the optical wiring 11 was fixed in the hollow pipe 30. At this time, the distance between the outer wall 2002 (side wall) of the mold 20 corresponding to the end face 54 of the optical substrate 50 and the incident / exit end face 12 of the optical wiring 11 was set to 50 μm.

  Next, as shown in FIG. 15, the cavity 20A of the mold 20 was filled with an optical waveguide material 40 (NTT-AT UV-curable epoxy optical waveguide material), and UV irradiation was performed.

  Next, as shown in FIG. 16, when the optical waveguide material 40 is cured, the hollow pipe 30 is removed from the mold 20, and the optical substrate 50 is removed from the cavity 20A as shown in FIG. It was.

The optical substrate 50 was connected to an optical fiber, and an insertion / extraction test was performed.
As a result, insertion loss fluctuation of ± 0.5 dB was confirmed after 1000 insertions.

(Example 2)
Next, Example 2 will be described.
First, as shown in FIG. 18, an optical wiring 10 was formed by applying a core material 90 (NTT-AT UV-curable epoxy optical waveguide material) on a core mold 80 and irradiating with UV.

  Next, as shown in FIG. 19, the optical wiring 10 was cut | disconnected by arbitrary length, and the optical wiring 11 was created.

  Next, as shown in FIG. 20, the optical wiring 11 was inserted into a funnel-shaped hollow pipe 31 installed on the side surface of the mold 20.

  Next, as shown in FIG. 21, the optical wiring 11 was fixed in the hollow pipe 31. At this time, the distance between the outer wall 2002 (side wall) of the mold 20 corresponding to the end face 54 of the optical substrate 50 and the incident / exit end face 12 of the optical wiring 11 was set to 50 μm.

  Next, as shown in FIG. 22, the mold 20 was filled with an optical waveguide material 40 (NTT-AT UV curable epoxy optical waveguide material) and irradiated with UV.

  Next, as shown in FIG. 23, when the optical waveguide material 40 is cured, the hollow pipe 30 is removed from the mold 20, and the optical substrate 50 is removed from the cavity 20A as shown in FIG. It was.

  The optical substrate 50 was connected to an optical fiber, and an insertion / extraction test was performed. As a result, insertion loss fluctuation of ± 0.5 dB was confirmed after 1000 insertions.

(Example 3)
Next, Example 3 will be described.
A refractive index matching agent 70 was filled in the recess 56 of the end face 54 of the optical substrate 50 created in Example 1 shown in FIG.

  The optical substrate 50 was connected to an optical fiber, and insertion loss measurement was performed. As a result, it was confirmed that the insertion loss was improved by about 0.8 dB by filling the refractive index matching agent 70.

As described above, according to the present embodiment, the following effects are produced.
First, the input / output end face 12 of the optical wiring 11 is displaced to the inside of the substrate main body 52 with respect to the end face 54 of the substrate main body 52, so that the input / output of the optical wiring 11 is physically connected to a quartz optical fiber or the like. Breakage of the end face 54 can be prevented. This has the effect of improving long-term reliability when the connector is connected.

  Second, the concave portion 56 of the optical substrate 50 is formed in a funnel shape in which the cross-sectional area gradually increases from the incident / exit end surface 12 toward the end surface 54 of the substrate body 52, so that it can be physically connected to a quartz optical fiber or the like. The positions of the input / output end face 12 and the end face of the optical fiber 6 can be automatically matched and joined. This improves the connection position accuracy and has the effect of reducing manufacturing costs.

  Thirdly, by filling the concave portion 56 of the optical substrate 50 with the refractive index matching material 70, the refractive index difference between the optical wiring 11 and the optical fiber 60 can be reduced. This has the effect of improving the optical connection characteristics.

In the embodiment, the optical substrate 50 has been described. However, the present invention is naturally applicable to an optical component and an electronic apparatus having such an optical substrate 50, and in particular, precise adjustment is not performed. However, alignment is easy, and the waveguide side is not damaged by contact with the optical fiber, so that specialized handling is not required. It is suitable not only for business use but also for household optical parts and electronic devices.
That is, examples of the optical component include an optical interconnection (photoelectric wiring board), an optical connector, an optical coupler, an optical coupler, an optical switch, an optical splitter, and an optical transceiver.
The optical component including the optical substrate according to the present invention can prevent damage to the optical waveguide (input / output end face 12 of the optical wiring 11) even when the connection with the optical fiber is repeated, and the connection with the optical fiber is easy. There is an effect that the working time is shortened.
In addition, examples of the electronic device include information / communication devices with large input / output such as a personal computer (including a large computer for business use), a telephone set, a home game machine, a recording / playback device, a television set, and a router. It is done.
The electronic device provided with the optical substrate of the present invention can prevent damage to the optical waveguide (input / output end face 12 of the optical wiring 11) even if the connection with the optical fiber is repeated, and the connection with the optical fiber is easy. There is an effect that the working time is shortened.

It is explanatory drawing of the manufacturing method of the optical board | substrate of this invention. It is explanatory drawing of the manufacturing method of the optical board | substrate of this invention. It is explanatory drawing of the manufacturing method of the optical board | substrate of this invention. It is explanatory drawing of the manufacturing method of the optical board | substrate of this invention. It is explanatory drawing of the manufacturing method of the optical board | substrate of this invention. It is explanatory drawing of the manufacturing method of the optical board | substrate of this invention. It is explanatory drawing of the manufacturing method of the optical board | substrate of this invention. It is explanatory drawing of the manufacturing method of the optical board | substrate of this invention. It is explanatory drawing of the manufacturing method of the optical board | substrate of this invention. It is explanatory drawing of the manufacturing method of the optical board | substrate of this invention. 6 is an explanatory diagram of a method for manufacturing an optical substrate in Example 1. FIG. 6 is an explanatory diagram of a method for manufacturing an optical substrate in Example 1. FIG. 6 is an explanatory diagram of a method for manufacturing an optical substrate in Example 1. FIG. 6 is an explanatory diagram of a method for manufacturing an optical substrate in Example 1. FIG. 6 is an explanatory diagram of a method for manufacturing an optical substrate in Example 1. FIG. 6 is an explanatory diagram of a method for manufacturing an optical substrate in Example 1. FIG. 6 is an explanatory diagram of a method for manufacturing an optical substrate in Example 1. FIG. 10 is an explanatory diagram of a method for manufacturing an optical substrate in Example 2. FIG. 10 is an explanatory diagram of a method for manufacturing an optical substrate in Example 2. FIG. 10 is an explanatory diagram of a method for manufacturing an optical substrate in Example 2. FIG. 10 is an explanatory diagram of a method for manufacturing an optical substrate in Example 2. FIG. 10 is an explanatory diagram of a method for manufacturing an optical substrate in Example 2. FIG. 10 is an explanatory diagram of a method for manufacturing an optical substrate in Example 2. FIG. FIG. 10 is an explanatory diagram of a method for manufacturing an optical substrate in Example 2. 10 is an explanatory diagram of a method for manufacturing an optical substrate in Example 3. FIG. (A), (B) is explanatory drawing of the hollow pipe 30 and the optical wiring 11. FIG. It is explanatory drawing of the malfunction in a prior art.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 ... Optical wiring, 11 ... Optical wiring, 20 ... Mold, 30 ... Hollow pipe, 31 ... Hollow pipe, 40 ... Optical waveguide material, 50 ... Optical substrate, 60 ... Optical fiber, 70 ... refractive index matching material, 80 ... core type, 90 ... core material.

Claims (12)

A substrate body;
An optical waveguide core embedded in the substrate body,
An input / output end face located at an end of the optical waveguide core is an optical substrate facing the end face of the substrate body,
The incident / exit end face is deviated inside the substrate body from the end face of the substrate body,
An optical substrate characterized by that. A recess is provided on the end surface of the substrate body,
The incident / exit end surface constitutes the bottom surface of the recess,
The optical substrate according to claim 1. The concave portion is formed in a funnel shape having a cross-sectional area that gradually increases from the incident / exit end surface toward the end surface of the substrate body,
The optical substrate according to claim 2. The substrate body and the optical waveguide core are both made of synthetic resin.
The optical substrate according to any one of claims 1 to 3, wherein the optical substrate is any one of the above. The recess is filled with a refractive index matching agent,
The optical substrate according to claim 2 or 3, wherein A plurality of the optical waveguide cores are provided,
The optical substrate according to claim 1, wherein the optical substrate is a substrate. A recess is provided on the end surface of the substrate body,
The incident / exit end surface constitutes the bottom surface of the recess,
The distance between the end face of the substrate body and the incident / exit end face is 10 to 500 μm,
The optical substrate according to claim 1, wherein: A linear optical waveguide core is cut into a predetermined length,
A hollow pipe having a dimension longer than the thickness of the wall portion of the mold is inserted in advance in a portion corresponding to both end faces of the optical substrate of the mold having a cavity having a shape corresponding to the optical substrate to be manufactured. Every
Inserting both ends in the longitudinal direction of the cut optical waveguide core into the hollow pipe,
Pour molten synthetic resin for forming the substrate body of the optical substrate into the cavity,
When the synthetic resin is cured, the hollow pipe is removed from the mold, and the optical substrate is taken out from the cavity.
An optical substrate manufacturing method characterized by the above. When the hollow pipe is removed from the mold, a concave portion is formed on the end surface of the optical substrate by the removed hollow pipe,
The incident / exit end face of the optical waveguide core constitutes the bottom face of the recess,
Filling the recess with a refractive index matching agent;
The method of manufacturing an optical substrate according to claim 8. The optical substrate to be manufactured has a plurality of optical waveguide cores,
Hollow pipes are respectively inserted corresponding to the plurality of optical waveguide cores at locations corresponding to both end faces of the optical substrate of the mold.
The method for producing an optical substrate according to claim 9.   An optical component comprising the optical substrate according to claim 1.   An electronic device comprising the optical substrate according to claim 1.

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