JP2975504B2 - Optical fiber fixing members - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical fiber fixing member used for connecting an optical fiber to an optical circuit.

[0002]

2. Description of the Related Art Quartz glass, ceramic or silicon is usually used as an optical fiber fixing member. After fixing an optical fiber at a desired position on a substrate, the optical axis between the optical fiber and the optical circuit is adjusted. It was adjusted and bonded and fixed. In this case, it is desirable that the height of the optical fiber fixing substrate be a height that does not require optical axis adjustment in the height direction.

FIG. 3 is a side view for connecting the optical fiber 1 and the optical waveguide 6 when quartz glass is used as the optical fiber fixing substrate 8. In this conventional example, four V-grooves 4 made of quartz glass and parallel to the surface of an optical fiber fixing substrate 8 having a rectangular parallelepiped shape are formed. The interval between the V grooves 4 is
The distance between the optical waveguides 6 is the same as that described below. Then, the optical fiber 1 is inserted into each of the V-grooves 4 of the optical fiber fixing substrate 8, and from the upper part, an optical fiber of quartz glass made of the same material as the optical fiber fixing substrate 8 to make the thermal expansion coefficients coincide with each other. Place the holding block 7 and fix it. And
The cross section perpendicular to the optical axis of the optical fiber 1 and the optical waveguide 6 is
The position is determined by adjusting (aligning) the position at which the coupling efficiency of the two is maximized. Thereafter, for example, an ultraviolet-curing adhesive is applied to the connection section between the optical fiber 1 and the optical waveguide 6 and the common substrate 5.
To the surface to be connected with, and adhesively fixed.

FIG. 4 shows an optical fiber 1 and an optical waveguide 6 when ceramic (for example, alumina or zirconia) or silicon is used as the optical fiber fixing substrate 10.
FIG. In this embodiment, the connection procedure is the same as that in the case where the optical fiber fixing member is made of quartz glass, but the optical fiber fixing member is made of ceramic and silicon and uses a thermosetting adhesive because it does not transmit light. And fix it.

[0005]

However, when quartz glass is used as the optical fiber fixing member, if the thickness of the optical fiber fixing member is small, the strength of the optical fiber fixing member becomes weak, and the handling and long-term reliability are reduced. A problem arises in sex. Therefore, there is a problem that the thickness of the optical fiber fixing member is limited.

Further, when ceramic or silicon is used for the optical fiber fixing member, the ceramic and silicon do not transmit light. Therefore, when the optical fiber fixing member also includes an optical fiber fixing member as a bonding cross section, a thermosetting adhesive is used. Must be used. Therefore, it takes time to cure the adhesive, and during that time, the optical fiber fixing member and the optical circuit are fixed firmly with sub-micron order temporal fluctuation so that the alignment power where the coupling power is maximum does not deviate from the alignment position There was a problem that had to be done. In order to solve this problem, there is a method of using an ultraviolet-curing adhesive as an adhesive, but since it can be used only near the surface, which is a portion that can be irradiated with ultraviolet light, the entire connection cross section cannot be cured. , There was a problem of being vulnerable to impact.

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and has as its object to form a material having a high strength capable of transmitting light such as ultraviolet light, thereby forming a connection between an optical fiber and an optical waveguide. An object of the present invention is to provide an optical fiber fixing member that can easily perform bonding work and can surely connect.

[0008]

SUMMARY OF THE INVENTION The present invention has been made to solve these problems, and an optical fiber fixing member used for connecting an optical fiber to an optical waveguide has a desired optical fiber. An optical fiber fixing substrate for fixing to a position and a holding block for holding an optical fiber set at a desired position on the surface of the optical fiber fixing substrate are formed of a light-transmitting polycrystalline Y ₃ Al ₅ O ₁₂ (light-transmitting). Polycrystalline yttrium-aluminum-garnet). Hereinafter, the translucent polycrystalline Y ₃ Al ₅ O ₁₂ is referred to as translucent polycrystalline YAG.

[0009]

The optical fiber is set at a desired position on the surface of the optical fiber fixing substrate of the transmissive polycrystalline YAG, and the fixing block of the translucent polycrystalline YAG of the same material is placed and fixed on the optical fiber. Have been. Transparent polycrystalline YA
Since G has a light transmitting property, the optical fiber fixing member transmits light, and since it is polycrystalline, there is no variation in strength as compared with quartz glass. For this reason, the thickness of the optical fiber fixing substrate can be made thin so that the fixed optical fiber and the core of the optical waveguide coincide with each other. Only in the horizontal direction of the vertical section. In addition, since it is translucent, it becomes possible to apply and cure a photocurable adhesive over the entire bonding cross section, and to increase the adhesive strength.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a perspective view showing an embodiment of an optical fiber array using an optical fiber fixing member according to the present invention. As shown in the figure, the optical fiber fixing substrate 3 is made of translucent polycrystalline YAG. On the surface of the optical fiber fixing substrate 3, four V grooves 4 for fixing the optical fiber are provided at the core interval of the optical circuit. Translucent polycrystalline Y
AG is disclosed, for example, in Japanese Patent Application No. 4-2576 by the present applicant.
No. 95, "Method for producing translucent yttrium-aluminum-garnet sintered body". According to this, the thickness of the optical fiber fixing substrate 3 is higher in Vickers hardness than quartz glass in terms of strength. , About 1.3 times, and the bending strength is about 4.4 times strong, so that the optical fiber has a thickness such that the core 11 of the optical waveguide 6 and the core of the optical fiber 1 fixed to the optical fiber fixing substrate 3 match. The fixing substrate 3 can be formed. In addition, in the flat portion having the step, the portion where the coating of the optical fiber is not removed is fixed. The optical fiber holding block 2 is a translucent polycrystalline YAG made of the same material as that of the optical fiber fixing substrate 3, and the thick portion of the optical fiber holding block 2 is a portion for holding the optical fiber core wire. The thin part presses the covering part. Here, the lateral width of the optical fiber fixing substrate 3 and the optical fiber holding block 2 is the same width as the optical waveguide 6, and the optical fiber fixing substrate 3, the optical fiber holding block 2 and the optical fiber 1 are After the addition of a photo-curable adhesive, for example, an ultraviolet-curable adhesive, the optical fiber array is manufactured by irradiating ultraviolet rays from the periphery of the connection portion and fixing the connection. Here, the adhesive to be used is not limited to the photocurable adhesive, and may be a thermosetting adhesive.
Hereinafter, an example of connection with the optical waveguide 6 using the optical fiber array having such a configuration will be described.

FIG. 2A is a side view of one embodiment showing the connection between the optical fiber array and the optical waveguide 6 of the present embodiment. The common substrate 5 is a rectangular parallelepiped, and centers the optical fiber array and the optical waveguide 6 on the common substrate 5. At this time,
Since the positions of the cores of the optical fiber 1 and the optical waveguide 6 are made to be the same height in the thickness direction of the optical fiber fixing substrate 3, only the width direction of the optical fiber array is adjusted. Core. Thereafter, an ultraviolet curing adhesive is applied to the connection surface of the optical waveguide shown in FIG. 2B and the connection surface of the optical fiber array shown in FIG. The optical fiber 1 and the optical waveguide 6 connected to the common substrate 5 are bonded and fixed with, for example, a thermosetting adhesive. Here, the optical waveguide 6 may be an optical fiber array.

Although the embodiment of the present invention has been described in detail, the present invention is not limited to this, and for example, the following modifications are possible.

In the above embodiment, the optical fiber fixing substrate 3
Although the V-groove 4 is used for positioning the optical fiber above, for example, another concave shape or a concave portion may be formed on the lower surface of the optical fiber holding block 2.

In the above embodiment, the common substrate 5 is used. However, the common substrate 5 may not be used and the positioning may be performed by using the guide pins to maximize the coupling efficiency.

[0015]

As described in detail above, the optical fiber fixing member using the translucent polycrystalline YAG according to the present invention has the following excellent effects.

Since light is transmitted, a light-curing adhesive such as ultraviolet light can be used for connection with the optical waveguide and fixing of the optical fiber, and the connection and fixing time can be shortened.

Compared to the case where quartz glass is used, the strength is superior, so that the thickness of the optical fiber fixing substrate can be reduced.

[Brief description of the drawings]

FIG. 1 is a perspective view showing one embodiment of an optical fiber array using an optical fiber fixing member according to the present invention.

FIG. 2A is a side view of an embodiment showing connection between an optical fiber array and an optical waveguide, and FIG. 2B is a connection cross-sectional view of the optical fiber array and the optical waveguide.

FIG. 3 is a side view of a conventional example showing connection between an optical fiber array and an optical waveguide when quartz glass is used as an optical fiber fixing member.

FIG. 4 is a side view of a conventional example showing a connection between an optical fiber array and an optical waveguide when silicon and ceramic are used as an optical fiber fixing member.

[Explanation of symbols]

1 Optical fiber 2 Optical fiber holding block (translucent polycrystalline YA
G) 3 Optical fiber fixing substrate (translucent polycrystalline YAG) 4 V groove 5 Common substrate 6 Optical waveguide 7 Optical fiber holding block (quartz glass) 8 Optical fiber fixing substrate (quartz glass) 9 Optical fiber holding block (Glass glass) (Silicon or ceramic) 10 Optical fiber fixing substrate (silicon or ceramic) 11 Optical waveguide core

Claims (1)

(57) [Claims] An optical fiber fixing member for fixing an optical fiber and connecting to another optical waveguide is a light-transmitting polycrystalline YA.
An optical fiber fixing member made of G.