JP3160155B2 - Optical communication component with built-in optical filter and method of manufacturing the same - 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 communication system having an optical filter, which is used for optical fiber communication and converts an optical signal propagating through the optical fiber into a different optical fiber after converting its characteristics with a filter or the like. The present invention relates to a component and a method for manufacturing the same.

[0002]

2. Description of the Related Art Conventional optical communication components incorporating an optical filter include an optical connector type in which an optical connector ferrule is connected in opposition and an optical connector embedded type in which an optical filter is embedded in a ferrule of an optical connector.

FIG. 3 shows an example of an optical connector type. Ferrules 101 and 102 attached to the tip of an optical fiber are inserted into a precision sleeve 103 from both ends, and an optical filter 104 is interposed therebetween. On the other hand, as an example of the optical connector embedded type, as shown in FIG.
The optical filter 113 is inserted into the slit 112 and fixed with an optical adhesive 114.

As the optical filter 113, use of an attenuating film, a wavelength filter (bandpass, blocking), or the like can be considered.

[0005]

However, in the optical connector type, it is necessary to polish opposing end faces and adjust and fix the end faces in a precision sleeve, which requires time for assembly. In the optical connector embedded type, it is necessary to slit the optical connector ferrule and the like together, which requires a large amount of processing, not only takes time, but also makes it difficult to form a narrow slit.

Further, the function of using an optical filter that reflects a part of the light and taking light in and out of the optical fiber from the side is difficult in any of the above-mentioned types. Depending on the angle, the light is reflected from the exit surface of the side surface.Therefore, additional processing such as attaching, shaving, or polishing a prism on the side surface, or a lens or the like is required to reduce light transmission loss. Met.

An object of the present invention is to solve the above-mentioned problems, to provide an optical communication component having a built-in optical filter, which is compact, has a small number of parts or processing steps, is excellent in mass productivity, and is capable of inputting and outputting optical signals from the side. Is what you get.

[0008]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention relates to an optical signal which is obtained by converting an optical signal propagating in an optical fiber into a different optical fiber after changing its characteristics with a filter or the like. The following problems can be solved in an optical communication component with a built-in filter.

A holding member for fixing a part of the optical fiber,
An optical communication component with a built-in optical filter by using a structure that consists of a slit that cuts the optical fiber at a predetermined angle to the optical axis of the optical fiber and an optical filter that is fixed to the slit with an optical adhesive Can be. By reducing the thickness of the fixing layer fixing the optical fiber to the holding portion to 10 times or less the thickness of the slit, it is possible to process a slit having a small processing depth, a short time, and a narrow width.

In addition, the optical fiber is not fixed to the holding portion but is formed integrally with the embedded optical fiber when forming the holding portion. Man-hours are reduced, and mass productivity is improved. The holding portion can be easily formed into a complicated shape and can be mass-produced by forming the holding portion from a resin or by using a sol-gel method using glass.

Further, by making the holding portion transparent, it is possible to put light into and out of the optical fiber from the side surface of the holding portion. In addition, a prism, a lens, a flat substrate (an optical surface for putting light in and out), etc. Optical components can also be formed on the side of the holding part. In addition, the loss of the light to be transmitted can be further reduced by cutting the portion of the optical fiber where the diameter of the light guide portion of the optical fiber is increased by heat with the slit.

[0012]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is an optical filter component with a built-in optical filter according to a first embodiment of the present invention, and FIG. 2 is a perspective view of the same embodiment. FIG. 9 is a perspective view of the holding member 2 in FIGS.

As shown in FIG. 9, a groove 91 for mounting an optical fiber and a groove 92 for mounting an optical fiber are formed on the upper surface of the holding member 2. The optical communication component with a built-in optical filter according to the first embodiment of the present invention comprises an optical fiber 1 fixed to a groove on the upper surface of a holding member 2 with an epoxy adhesive 3.
And a slit 4 for cutting the optical fiber 1 and a slit 4
And an optical filter 6 fixed with an optical adhesive 5.

In the manufacturing method, first, the nylon coating 7 in the middle of the optical fiber is peeled off to expose the strand 1 of the optical fiber. The element wire 1 is placed on a groove formed on the holding member 2, and after pouring an epoxy-based adhesive or a resin 3, it is cured and fixed. At the center of the holding member 2, a groove 8 is dug in a U-shape. At the groove 8, a slit 4 for cutting the wire 1 is formed on the epoxy adhesive 3 at a predetermined angle with respect to the optical axis of the wire 1 by a dicing saw. Next, the optical filter 6 is inserted into the slit 4 and fixed with the optical adhesive 5. Since the amount of application is adjusted so that the surface of the epoxy-based adhesive or the resin 3 is approximately the same height as the upper surface of the strand 1, the processing depth is small and the slit processing can be performed in a short time. Further, in general, in slit processing with a dicing saw, the depth of the slit is limited to the thickness of the blade. For example, when a slit with a width of 50 μm is processed, the depth of the slit is 500
The limit is about μm. In this structure, the processing depth can be as small as 125 μm, which is the minimum diameter of the optical fiber, so that even a dicing saw can process a slit having a considerably narrow width. Therefore, in the present application, the lower portion of the wire 1 is located at a position 10 times or less the width of the slit from the surface of the adhesive or resin layer 3 on the upper surface of the wire 1. As the holding member, a material having a thermal expansion coefficient equal to or close to that of glass is desirable, and glass or zirconia may be used.

FIG. 5 is a perspective view showing a second embodiment of the present invention. The optical fiber 1, a holding part 201 formed by embedding the optical fiber 1, a slit 4 for cutting the optical fiber 1, and an optical adhesive 5
And an optical filter 6 fixed at

The manufacturing method is as follows. First, the bare wires 1 exposed in the middle of the optical fiber are solidified with a resin, and are integrally formed in such a manner that the wires 1 are embedded in a holding portion 201 where the resin is solidified. Next, at a predetermined angle with respect to the optical axis of the wire 1,
The slit 4 that cuts is processed. Furthermore, slit 4
Then, the optical filter 6 is inserted and fixed with the optical adhesive 5.

The solidified position of the wire 1 is a position not more than the thickness of the slit from the resin surface.
As in the embodiment, a thin slit can be formed in a short time. FIG. 6 is a perspective view showing a mold used in the second embodiment of the present invention, in which the optical fiber 1 is embedded in the holding portion 201 and made integrally with resin.

Each of the molds 211 and 212 has a clamp portion 213 for sandwiching an optical fiber. The strand 1 is fixed to the clamp portion 213 while being stretched straight. Then, the mold 211, 2
The resin is poured into the mold 12 and the molds 211 and 212 are tightened and hardened. After the resin has hardened, remove the mold. , Which
It is possible to reduce the size and the number of parts and processing steps,
Mass productivity is improved.

FIG. 7 is a perspective view showing a third embodiment of the present invention. The configuration is the same as that of the second embodiment. Specifically, the wire 1 exposed in the middle of the optical fiber
Is a holding portion 30 made of glass by a sol-gel method.
It is embedded in one. That is, for example, the silica sol is poured into a predetermined mold in a state in which the element wire 1 is embedded, and then gelled and extruded from the mold. Thereafter, it is dried and sintered to obtain glass. The holding part 301 is made of a transparent material having the same refractive index as the clad part of the optical fiber 1.
A lens 302 formed on a spherical surface is formed on one side surface. Further, a slit 4 for cutting the wire 1 is formed at a predetermined position of the solidified holding portion 301 at a predetermined angle with respect to the optical axis of the wire 1. Further, the optical filter 6 is inserted into the slit 4 and fixed with the optical adhesive 5.

The optical filter 6 reflects a part of the light and transmits the remaining light. Part of the light entering from the side a is reflected by the optical filter 6 and enters the photodetector 303 from the lens 302 on the side surface of the holding unit 301. This is an optical communication component for observing light being transmitted.

Conversely, the lens 302 on the side of the holding portion 301
A light source may be disposed on the side and a photodetector may be disposed on the side b, so that a single-core optical communication component can be used. The holding portion 301 is formed by clamping the optical fiber and forming the wire 1
Are formed by the sol-gel method in such a manner as to embed. As a result, not only the number of components and the number of processing steps can be reduced, but also optical components such as prisms and lenses can be formed on the side surface of the holding portion 301 without additional or additional processing.

Incidentally, it is also possible to form a higher-performance optical component by forming a distribution of the refractive index around the element wire 1 of the holding portion 301. FIG. 8 is a sectional view showing a fourth embodiment of the present invention. The structure is such that the coating is peeled off in the middle of the optical fiber, the central part of the wire 1 is heated, and the core 4 which is the light guide part is heated.
The mode field diameter of No. 01 is enlarged to about three times, and is fixed to the holding portion 2 with an epoxy adhesive 3. The slit 4 is formed so as to cut the strand 1 at a predetermined angle when the mode field diameter becomes large. An optical filter 6 is inserted into the slit 4 and is fixed with an ultraviolet curing adhesive 5. Increasing the mode field diameter can further reduce the loss of transmitted light. The mode field diameter is the diameter of the light guide section whose core diameter is defined by the refractive index, whereas the mode field diameter represents the diameter of the light guide section through which actual light passes.

[0023]

According to the present invention, there is provided an optical communication component having a built-in optical filter for coupling an optical signal propagating in an optical fiber to a different optical fiber after converting characteristics of the optical signal with a filter or the like. The part is fixed to the holding member, and the fixing layer is subjected to slit processing for cutting the optical fiber at a predetermined angle with respect to the optical axis of the optical fiber. Next, an optical filter is inserted into the slit and fixed with an optical adhesive. Since the optical fiber is fixed from the surface of the fixing layer to about 10 times or less of the slit width, the processing depth is small, and the processing of the narrow slit can be performed in a short time.

Further, by integrally forming the optical fiber into the holding portion so as to be embedded therein, not only the size is reduced, but also the number of parts and the number of processing steps are reduced, and mass productivity is increased. The holding portion can be made of resin or glass by a sol-gel method. Further, by making the holding portion transparent, it is possible to allow light to enter and exit from the side surface of the optical fiber, and to form optical components such as a prism and a lens on the side surface of the holding portion.

Further, the loss of the transmitted light can be further reduced by heating the optical fiber section cut by the slit and expanding the mode field diameter of the light guide section.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a first embodiment of the present invention.

FIG. 2 is a perspective view showing an optical communication component with a built-in optical filter according to the first embodiment.

FIG. 3 is an explanatory view showing an example of a conventional optical communication component.

FIG. 4 is an explanatory view showing another example of a conventional optical communication component.

FIG. 5 is a perspective view showing an optical communication component with a built-in optical filter according to a second embodiment.

FIG. 6 is a perspective view of a mold for hardening a resin in the second embodiment.

FIG. 7 is a perspective view showing a component for optical communication with a built-in optical filter according to a third embodiment.

FIG. 8 is a perspective view illustrating an optical communication component with a built-in optical filter according to a fourth embodiment.

FIG. 9 is a perspective view of a holding member used in the optical communication device with a built-in optical filter according to the first embodiment.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 optical fiber (elementary wire) 2 holding member 4 slit 5 optical adhesive 6 optical filter 8 groove 201 301 holding section 211, 212 type 401 core (light guide section)

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-2-267501 (JP, A) JP-A-4-141604 (JP, A) JP-A-5-232322 (JP, A) 101201 (JP, U) JP 3-19524 (JP, B2) (58) Fields investigated (Int. Cl. ⁷ , DB name) G02B 6/00 G02B 6/26 G02B 6/36

Claims (5)

(57) [Claims] 1. An optical fiber comprising: an optical fiber;
A holding member for partially mounting, and a slit for cutting the wire at a predetermined angle with respect to the optical axis of the wire of the optical fiber,
An optical filter component with a built-in optical filter having an optical filter fixed to the slit, comprising: an adhesive layer or a resin layer formed by embedding element wires of the optical fiber on an upper surface of the holding member. Features Optical communication components with built-in optical filters. 2. A fiber, a strand of the optical fiber
A holding part formed by the sol-gel method
And cutting the wire at a predetermined angle with respect to the optical axis of the serial wire
An optical communication component with a built-in optical filter, comprising: a slit formed; and an optical filter fixed to the slit. 3. An optical fiber and a part of the optical fiber are fixed.
A constant the holding member, the slits for cutting the optical fiber, the optical <br/> Studies manufacturing method of built-in filter component for optical communication comprising a optical filter that is fixed to the slit, the coating of the optical fiber Exposing the stripped optical fiber
And an adhesive layer or a tree forming a slit in the exposed strand.
On the upper surface of the holding member having a groove for forming a grease layer, the groove is
Placing the wire under the wire, pouring an adhesive or resin into the groove, and embedding the wire.
And fix the wire on the upper surface of the holding member.
At a predetermined position with respect to the optical axis of the optical fiber at the groove.
Forming a slit for cutting the element wire at an angle, and inserting and fixing the filter in the slit.
A method for manufacturing an optical communication component with a built-in optical filter . 4. The step of exposing a strand of the optical fiber.
Then, the portion of the wire into which the slit enters is heated, and the wire is heated.
Claims characterized by having a step of enlarging the core diameter of
Item 4. A method for producing an optical communication component with a built-in optical filter according to Item 3. 5. An optical fiber and a part of said optical fiber are fixed.
The holding portion, and the holding portion traverses the optical fiber.
Optical filter built-in light consisting of an optical filter provided
In a method for manufacturing a communication component, a sheath of an optical fiber is stripped to expose an optical fiber.
And the entire lower part from the upper surface of the exposed strand is integrated.
Forming the holding part embedded in the sol-gel method
Place the embedded wire with respect to the optical axis of the optical fiber.
Forming a slit to cut at a fixed angle,
Inserting the filter into a filter and fixing the filter.
For manufacturing optical communication components with built-in optical filters.