JPH08240739A - Method for connecting optical parts and optical parts - Google Patents

Abstract

PURPOSE: To simplify the work to protect the entire part of optical parts by coating these optical parts including the optical path junctures between the optical parts with an adhesive so as to cover the surfaces of the optical parts on both sides. CONSTITUTION: The optical parts 10, 20, 30 are immersed into the adhesive 52 in an uncured liquid form and at least the optical connecting area is sunk under the liquid surface of the adhesive 52. The optical parts are aligned in the state of embedding the parts into the adhesive and thereafter, the adhesive 52 in cured. The alignment is executed by aligning the end faces of the optical fibers, more preferably the centers of the core, thereby minimizing the optical connection loss and finely adjusting the mutual positions until the light power to be transmitted is maximized. A UV adhesive of an epoxy system or acrylate system having the refractive index approximate to the refractive index of the cores, etc., to be aligned is used for the optical adhesive 52. In such a case, the alignment is executed in the state of immersing the optical parts into the optical adhesive 52 and, therefore, the subsequent occurrence of misalignment by the intervention of the adhesive between the end faces of the optical parts like in alignment in the air does not arise any more.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical component and an optical component, for example, an optical waveguide type optical coupler, an optical multiplexer and the like and an optical fiber (or an optical fiber array), or optical waveguides or an optical fiber (or an optical fiber). Arrays) for connection of each other.

[0002]

2. Description of the Related Art Currently, the following are used to connect optical components to each other.
Three methods are used. Fusion: The connection points between parts are fusion-bonded by laser. Adhesion: Adhesion is performed with an adhesive whose refractive index is matched to the values of both optical paths. Mechanical contact: The optical path ends are pressed against each other with a constant pressure. Among these, adhesion is predominant because of low loss, low cost, easy connection process, and the like.

An example of a conventional method for connecting optical components by adhesion will be described. FIG. 4 shows the optical component 2 on both sides of the optical component 10.
This is the case of connecting 0 and 30 (Japanese Patent Laid-Open No. 2-77704).
(See the official gazette). The optical component 10 is, for example, a waveguide type splitter, and the optical component 20 is an input side optical fiber array.
Reference numeral 2 is an optical fiber, optical component 30 is an output side optical fiber array, and 32 is an optical fiber tape.

These are connected as follows. The connection surfaces of the optical components 10, 20, 30 are mirror-finished. Then, the optical path is aligned ((a) in the figure). Then, they are connected to each other by an optical adhesive 40 (FIG. 2B). After that, a coating 42 of, for example, a silicon resin is applied to the whole to form an optical component module 44 (FIG. 7C). After that, the metal case 46 is covered if necessary ((d) of the same figure).

[0005]

However, the above method has the following problems. For connecting the parts together and subsequent coating,
The adhesive is used twice, which hinders efficiency. The alignment is performed in air or in vacuum, but there is a possibility that the propagation of light may change due to subsequent application or adhesion of an adhesive and the optical axis may shift. Realigning after applying the adhesive is not efficient because it requires repeated work. Conventionally, the coating 42 is brushed, potted,
The shape is not constant because it is done by dipping. This is a disadvantage for automated processes such as metal casing including transportation.

[0006]

When connecting optical components, as shown in FIG. 1, the optical components 10, 20, 30 are connected.
Embedded in the optical adhesive 52, and in the embedded state, the optical component is aligned, and then the adhesive 5
Cure 2

Immersion in the optical adhesive 52 means that the optical components 10, 20, 30 are uncured liquid adhesive 52.
That is, at least the optical connection region is submerged below the liquid surface of the adhesive 52.

Alignment is to align the end faces of the optical fibers, preferably the centers of the cores, in parts having an optical path to minimize the optical connection loss, and in the case of parts having a lens, the optical axis is to be adjusted. It is to match. For alignment, a well-known power monitor method or the like is used, and the mutual positions are finely adjusted so that the transmitted optical power is maximized.

As the optical adhesive 52, an epoxy or acrylate UV adhesive having a refractive index similar to that of a centering core or the like is used. For example, epoxy-based Optodyne (trade name, manufactured by Daikin) can be preferably used.
The optical adhesive 52 is put in the adhesive tank 50. As described later, the inner surface shape of the adhesive agent tank 50 becomes the outer shape of the optical component module 56. If you use a normal square plate adhesive tank 50,
The optical component module 56 is a square block. Also,
For example, an optical component module 5 having a special shape as shown in FIG.
When making 6, adhesive tank 5 with the same inner surface shape as this
Use 0.

[0010]

[Operation] If alignment is performed while the optical component is dipped in the optical adhesive 52, it may be said that the alignment may occur in the air due to the interposition of the adhesive between the end faces of the optical component, like alignment in the air. Moreover, since a wide area including the adhesive portion is coated with a material having the same physical property, the influence of the temporal change of the optical connection state or the change of the physical condition is significantly reduced. The adhesive 52 doubles as the adhesion between the optical components and the coating of the connection components, and the two processes are completed in one process.

[0011]

EXAMPLE Referring to FIG. Here, there are various types of substrate-type waveguides such as SiO2 type, semiconductor crystal type, and dielectric crystal type, and all of them are formed on these substrates by a flame deposition method, a CVD method, or the like. A waveguide pattern is formed by forming a core layer and a clad layer by the photolithography technique. The example of FIG. 1 is an optical component 1.
This is a case where the optical components 20 and 30 are connected to both sides of 0. The optical component 10 is, for example, a waveguide chip component or an optical component 2
Reference numeral 0 is an input side optical fiber array, 22 is an optical fiber tape, optical component 30 is an output side optical fiber array, and 32 is an optical fiber tape. In these optical fiber arrays 20 (30), as shown in FIG. 3, an optical fiber 23 is placed on a flat glass plate 27 having a multi-core V groove 26 formed on its surface, and a glass lid 28 is placed thereon. It has a structure in which it is covered and fixed with an adhesive. Reference numeral 50 denotes an adhesive agent tank, which has, for example, an elongated rectangular dish shape. Reference numeral 52 denotes an optical adhesive, for example, an epoxy-based, acrylate-based, or modified acrylate-based UV (ultraviolet curing type) adhesive, which can be bonded in a short time by ultraviolet rays. The connection is
Do the following:

As shown in FIG. 1A, the optical components 10, 2
The holders 14, 24, and 34 (for example, suction holders) are attached to 0 and 30, respectively, and they are immersed in the adhesive 52 of the adhesive tank 50 and buried. In addition, the holders 14, 24, 3
4 may be of any type as long as it can be easily attached to and detached from the optical components 10, 20, 30 and can be held in the adhesive 52. In addition to the above-mentioned holder, for example, a clothespin with a stick may be used, but in any case, an actuator for changing the position of the holder is attached to the end portion (not shown) of the holder. While being buried in the adhesive 52, the position of the holder is appropriately changed in the vertical and horizontal directions of the paper and further in the depth direction,
The respective end faces of the optical components 10 to 20 and the optical components 10 to 30 are brought into contact with each other, and alignment is performed so that the end face of the optical fiber of the optical fiber array and the end face of the waveguide (core portion) of the intermediate waveguide chip are aligned ( The same figure (b)). Although not shown, the core portion of the waveguide is located slightly below the surface of the optical waveguide component.

As shown in FIG. 1C, the optical components 10 and 2
The ultraviolet ray 54 is spot-irradiated from above the optical path joint portion 102 of 0 and the optical path joint portion 103 of the optical components 10 and 30, and only the adhesive 52 in the vicinity thereof is cured (the cured portion of the adhesive 52 is indicated by a dark dot. Indicated). The holders 14, 24, 34 are attached to the optical components 10, 20, 30.
(Fig. 4 (d)). Even if it is removed, the optical components are not separated from each other. Further, since a part of the adhesive 52 is cured to the bottom of the tank 50, the optical component is not sunk by being supported by the adhesive 52. By changing the irradiation direction and area of the ultraviolet rays, the adhesive 52
The whole is cured by irradiation of ultraviolet rays 54 ((e) in the same figure).

The cured optical adhesive 52 (containing the connected optical components 10, 20, 30) is released from the adhesive tank 50 (FIG. 6F). This is the optical component module 5
It becomes 6. Thereafter, the optical component module 56 is covered with a metal case, if necessary. The holders 14, 24, 34 and the adhesive tank 50 are cleaned with a solvent or the like.

In the above method, the UV curing is initially performed only around the optical path joining portion 103, but it is also possible to cure the entire periphery of the component from the beginning, rather than the spot-like aiming. In addition, if the holder material is easily detached from the optical adhesive, it is not necessary to consider it so that ultraviolet rays are not irradiated around the holder, and depending on the holder material, it may remain in the optical adhesive after curing. Even if it stays, it does not adversely affect the product. Also, there may be holes after removing the holder,
Also in this case, since the volume of the hole is not so large, the influence on the characteristics is small.

[Applicable field of the present invention] In addition to the connection between the optical waveguide chip and the optical fiber described above, the present invention can be applied to the following fields. Connecting and protecting optical fibers. Connection and protection of optical fiber and lens. Mechanical and chemical protection for optical components.

Next, the adhesive is coated over the surfaces of the left and right optical components including the optical joining portion, and preferably, as shown in the drawing, the entire periphery of these optical components is coated with a thickness, but The entire optical component does not necessarily have to be embedded and embedded in the adhesive in order to omit the process of bonding and fixing the core. That is, the present invention can be implemented by using a jig container or the like in which a part (for example, only the upper half) of the optical component including the optical path joining portion is immersed in the adhesive. The product in this case is
Although the adhesive is coated so as to cover the surfaces of the optical components on both sides, the entire optical component is not enclosed in the adhesive. To cover the surfaces of the optical components on both sides,
It means that the coating layer is separated on the left and right sides and that the coating layer has some notches (holes).

[0018]

EFFECTS OF THE INVENTION Since the adhesive agent for bonding the optical parts simultaneously protects the entire assembly parts, the work of protecting the entire parts can be omitted. This leads to a reduction in production cost. At the time of alignment, it is possible to perform alignment with high accuracy and speed more quickly with alignment with an optical adhesive than with alignment with an air layer sandwiched between the optical path ends. Since the adhesive agent tank 50 can be used as a base material, the shape of the optical component module 56 can be made constant. Therefore, the subsequent casing becomes easy.

[Brief description of drawings]

FIG. 1 is an explanatory view showing an embodiment of the present invention in the order of steps.

FIG. 2 is an optical component module 56 that can be manufactured according to the present invention.
Explanatory drawing of an example.

FIG. 3 is a general explanatory view of an optical fiber array.

FIG. 4 is an explanatory view showing an example of a conventional technique in process order.

[Explanation of symbols]

 10, 20, 30 Optical parts 102, 103 Optical path joint part 14, 24, 34 Holder 22, 32 Optical fiber tape 23 Optical fiber 26 V groove 27 Glass plate 28 Glass lid 40 Adhesive 42 Coating 44 Optical part module 46 Metal case 50 Adhesive tank 52 Optical adhesive 54 UV light 56 Optical component module

Claims (2)

[Claims] 1. An optical component in which at least three or more optical components are aligned and connected with each other and fixed by an adhesive, and the surfaces of the optical components on both sides are covered including an optical path connecting portion between the optical components. Parts coated with the adhesive as described above. 2. When connecting an optical component, the optical component is embedded in an optical adhesive, the optical component is aligned in the embedded state, and then the adhesive is cured. How to connect parts.