JPH0421803A - Integrated optical fiber function parts - Google Patents

Abstract

PURPOSE:To obtain a parallel beam conversion system to be integrated adaptively to mass production by oppositely arranging grated index type (GI) optical fibers 5 having prescribed length and diameter on both the sides of grooves with a prescribed width formed on a substrate respective in parallel and allowing the optical axes of the opposed GI optical fibers to coincide with each other. CONSTITUTION:The continuous bodies of the GI optical fibers are embedded in respective optical fibers 3 so that the GI optical fibers 5 respectively having a prescribed length L are left on both the end parts of the upper face of a substrate 2 and grooves having prescribed depth D and width are cut on the intermediate part of the upper face of the base 2. The width of optical fiber holding parts 7 and the length L of the fibers 5 are set up in relation to the refractive index distribution format of the fibers 5. When the length L (corresponding to the width of each holding part 7) of plural fibers 5 held on the holding parts 7 in a ground state on both the end faces are set up to a proper length, incident light from one side can be collimated to parallel beams. Consequently, the parallel beam conversion system to be compacted and integrated obtained.

Description

Detailed Description of the Invention [Industrial Application Field] The present invention is an integrated optical fiber functional component IOFC (Inte
rated 0ptical fiber func
For details regarding tionalComponent),
The present invention relates to a functional component that can form a parallel beam conversion system by interposing a functional optical element or the like in an optical fiber waveguide for optical communication.

[Prior Art] An example of a conventional integrated optical fiber functional component (IOFC) of this type is shown in FIG. This example is a typical example used when interposing a functional optical element such as an optical isolator between optical fibers, where 100 is an optical fiber and 200 is a distributed index lens. In this way, by using the distributed index lens 200 and forming a parallel beam conversion system so that a parallel light beam 300 is obtained between them, the gap loss between the optical fibers 100 is reduced (suppressed). There is.

[Problems to be Solved by the Invention] However, the conventional 10FC as described above has the following problems.

(1) The diameter of the distributed index lens 200 is generally several mm, and the diameter of the normal optical fiber 100 is 0.125 m.
If a plurality of such optical fibers 100 are arranged at a pitch of about 0.25 mm, it is difficult to form a multi-core parallel beam conversion system. is difficult.

(2) Since the distributed index lenses 200 arranged at opposing positions are provided independently from each other, it is necessary to align the optical axes between both lenses 200.

(3) It is also necessary to align the optical axes between the optical fiber 100 and the distributed index lens 200, which requires the use of an alignment jig, and requires a high level of skill to properly fix both. It takes.

An object of the present invention is to focus on the above-mentioned conventional problems and to provide an integrated optical fiber functional component that can provide a parallel beam conversion system that can be integrated and is suitable for mass production.

[Means for Solving the Problems] In order to achieve this object, the present invention includes a plurality of GI optical fibers having a predetermined length and diameter facing each other on both sides of a groove of a predetermined width provided on a substrate. It is characterized in that the optical axes of the GI optical fibers arranged in parallel and facing each other are made to coincide with each other, so that a parallel beam conversion system can be obtained between the facing GI optical fibers.

[For production]

According to the present invention, a plurality of parallel GI optical fibers having predetermined lengths and diameters, which are disposed at opposing positions on both sides of a groove in which a functional optical element is interposed on a substrate, have their optical axes aligned with each other. In addition, the lengths of the GI optical fibers are set so that a parallel beam conversion system can be obtained between pairs of opposite GI optical fibers, so that the distribution of each GI optical fiber is It functions in place of a refractive index lens, allows miniaturization and integration, is suitable for mass production, and can realize a parallel beam conversion system for multiple optical fibers at once.

〔Example〕

Embodiments of the present invention will be described in detail and specifically below based on the drawings.

1 and 2 show one embodiment of the invention. In these figures, 1 is the substrate 10FC12 which constitutes 10FC1. 3 is a plurality of parallel optical fiber grooves formed on the substrate 2 by continuous processing, and 4 is a guide pin groove provided on both sides of the optical fiber groove 3 in the same direction. 5 is a GI optical fiber (graded index type optical fiber) embedded in each optical fiber groove 3 and held and adhesively fixed between the flat plate 6;
By arranging the I optical fiber 5 as shown in the figure, the G
By utilizing the characteristics of the I optical fiber, a parallel beam conversion system can be constructed as described later.

To do this, first, a continuous body of GI optical fibers 5 is buried in each optical fiber groove 3 as described above, and then GI optical fibers 5 of a predetermined length are left at both ends of the upper surface of the substrate 2. A groove 8 having a predetermined depth D (D>depth of optical fiber groove) and width is cut in the intermediate portion. In addition, the width of the optical fiber holding part 7 and the GI optical fiber 5 at this time
The length is set in relation to the refractive index distribution form of the GI optical fiber 5, and the plurality of GI optical fibers 5 held in the optical fiber holding part 7 with both ends polished
By appropriately setting the length L (corresponding to the width of the holding part), it is possible to collimate the light incident from one side into a parallel beam.

Reference numeral 9 denotes a clamper for holding the guide bin 1o in the guide pin groove 4. As shown in FIG. 2, by fitting the guide pin 10 into the guide pin groove 4 and attaching the clamper 9 from above as shown in the figure, the l0PCI It is possible to maintain a connected state between optical fibers (not shown) provided on both sides. Note that the guide pin groove 4 may not be shown or may be formed on the lower surface of the substrate 2.

In the 10PCI constructed in this way, the GI optical fibers 5 are buried in the parallel optical fiber grooves in advance, and the intermediate portions of the fibers are removed together with the substrate 2 to form the grooves 8, so that the grooves 8 are formed as shown in FIG. Holding part 7 divided into right and left parts
The axes of the GI optical fibers 5 held in the GI optical fibers 5 are completely aligned, and there is no need to adjust the axes as in the conventional example. Moreover, the length of these GI optical fibers 5 is determined in the groove 8.
Since the settings are made to obtain a parallel beam, l0
It is possible to freely plan the number of optical fibers connected to the PCI, that is, regardless of the number of GI optical fiber rows.

(A), (B) and (C) of FIG. 3 show the form in which the 10PCI according to the present invention is actually applied. In (A), the optical connector 4 is connected to the multi-core tape fiber 100A.
00 is provided, and each optical connector 400 is provided with a guide pin 10 protruding, and these guide pins lO
It is sufficient to fit the guide pin groove 4 against the guide pin groove 4 from the opposite direction of the l0PCI, and then fix it with the clamper 9.

In (B), the guide pin 1G that is continuous with the guide pin groove 4 of 10PCI is fixed in advance with the clamp 9. Mutual alignment can be obtained by inserting it into the female hole (not shown) of 400.
(C) is an example in which the 10PCI and the optical connector 400 are made into one package A from the beginning, and the connection does not necessarily require the guide pin to fit into the guide pin groove. Needless to say.

Figure 4 shows l0PCI and optical connector 4 as described above.
00 is shown coupled through the coupling surface 11. By being coupled in this way, individual 3M optical fibers 1
A parallel beam conversion system can be obtained by performing distributed refraction on the light passing through the GI optical fiber 5. As can be seen from this figure, the height Hl of the substrate 2 and the height H2 of the flat plate 6 are preferably set at the coupling surface 1 of the optical connector 400.
It is preferable to form the corresponding height in 1.

Thus, by embedding an optical element (not shown) in the parallel groove 8, one optical functional component such as an optical isolator, an optical switch, an optical coupler, an optical tap, an optical multiplexer/demultiplexer, an optical multiplexer/brancher, etc. can be formed. It becomes possible. Especially (C) in Figure 3.
In the case of the form shown in , alignment of the guide pin grooves and optical fiber guide grooves can be guaranteed by combining the optical connector and the optical connector in pairs on the same processing line when manufacturing 10FC:. Therefore, l0
It can be said that it is extremely suitable for mass production of optical functional parts using FC.

The present inventor further specified l0F as shown below.
C: and as a result of conducting experiments, we were able to achieve good results with extremely low coupling loss.

10 optical fiber grooves and 2 optical fiber grooves on a 1.5 mm thick Si wafer
The guide pin groove of the book was processed at a predetermined position, and a flat plate having a thickness of 0.5 mm was joined to form an optical fiber guide hole. Note that no flat plate is provided above the guide bin groove. Thus, the optical fiber groove has an outer diameter of 1
A GI optical fiber with 25 ILm and a focusing constant g of about 3 mm-' was inserted and fixed with adhesive. Both ends of the optical fiber holding portion to which the GI optical fiber was fixed were polished, and parallel grooves were further ground to a depth of about 1 mm. The total length of the board is approximately 3 mm+, and the length of the groove removed by polishing is approximately 1.8 mm, and GI optical fibers of approximately 0.60 mm length are attached to the optical fiber holders at both ends for parallel beam collimation. It was kept as. Then, ten SM optical fibers with an outer diameter of 125 μm were inserted and fixed into the fiber holding portion of an optical connector manufactured on the same processing line, and the end faces were polished to form a multi-core optical connector.

A SUS clamp is installed on the outside of the l0FC, and the clamp holds 4 φ0.7mm guide pins on each side.
It was fixed under pressure so that it protruded by mm.

A 5M10 multi-core optical connector was connected to this 10FC using matching oil, and a quartz glass coated with matching oil was inserted into the groove of 10FC for testing.

In this state, we measured the overall coupling loss between the 10FC and the optical connectors on both sides.
．． The loss was as low as 5 dB. There is a portion of the optical fiber that has been polished away, which is approximately 1.8 mm, and the coupling loss during this period is approximately 2d, considering the loss of the 3M optical connectors on both sides.
Since it is estimated to be less than B, it was possible to create a parallel beam conversion system that has low loss and can perform compact multi-core batch processing.

Therefore, by using this, it becomes possible to form various optical functional parts. Furthermore, by optimizing the focusing constant g and processing accuracy, it is possible to aim for lower loss.

In the above explanation, one 10FC was described, but in reality, mass production processing on a wafer scale is possible, and -
It has the great advantage of being able to be processed all at once.

Furthermore, in the above embodiment, the guide pin for coupling is pressed into the guide groove by a metal clamper, but l0
The connection between the FC and the optical connector is not limited to this, for example, by directly attaching a guide pin to the 10FC side by adhesive, etc. 1) Any method can be used as long as the two can be accurately positioned. There may be.

If the focus of l0PCI becomes a problem, create a space 1 of a certain length outside the GI optical fiber 5 as shown in FIG.
2 may be formed based on the design. Of course, it goes without saying that such a space may be formed on the optical connector side (not shown).

〔Effect of the invention〕

As described above, according to the present invention, (1) a parallel beam conversion system can be created according to the dimensions of an optical fiber, so miniaturization and integration are possible.

(2) A parallel beam conversion system can be realized for multiple optical fibers at once.

(3) Compatibility of coupling with conventional optical connectors can be obtained.

(4) Length dimension of space for inserting GI optical fiber and optical functional components easily by using grinding process] 2. In addition to being able to align, there is no need for conventional alignment work.

(5) Since the continuous GI optical fiber is embedded in the substrate with continuous grooves and then ground, there is no need for axial alignment as in the conventional case, and if necessary, it can be integrated with both connector parts. Can be manufactured.

(6) The structure allows multiple l0FCs to be processed at once on a wafer scale, so it is suitable for mass production processing.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing an example of the configuration of the 10FC of the present invention, FIG. 2 is a front view of the 10FC shown in FIG. 1, and FIG. 3 is an explanatory diagram showing various combinations of the 10FC of the present invention and an optical connector. Fig. 4 is a diagram of the path of a light ray when the IOFC of the present invention is coupled with an optical connector, Fig. 5 is an explanatory diagram of another embodiment of the invention (focal length guaranteed type), and Fig. 6 is a diagram of the conventional IOFC. FIG. 2 is an explanatory diagram of a parallel beam conversion system. 1...l0FC. 2... Substrate, 3... Optical fiber arrangement, 4... Guide pin vortex, 5... GI optical fiber, 7... Optical fiber holding part, 8... Parallel groove, 9... - Clamper, 10... Guide bino, 100... sM optical fiber, 100Δ... Multi-core tape fiber, 400... Optical connector.

Claims (1)

[Claims] 1) A plurality of GI optical fibers having a predetermined length and diameter are arranged in parallel and facing each other on both sides of a groove of a predetermined width provided on a substrate, and the optical axes of the opposing GI optical fibers are arranged in parallel. 1. An integrated optical fiber functional component characterized in that a parallel beam conversion system is obtained between the opposing GI optical fibers by making them coincide with each other. 2) Each pair of the plurality of opposing GI optical fibers is formed into one continuous real GI optical fiber before the groove of the predetermined width is provided.
The optical fiber is arranged and fixed in an optical fiber holding part formed across both sides of the groove, and then removed along the groove when forming the groove on the substrate, thereby forming the predetermined length. The integrated optical fiber functional component according to claim 1, characterized in that: