JPS5811604B2 - Multi-fiber optical connector - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a multi-core optical fiber connector, and particularly to a multi-core optical fiber connector that has a simple structure and can connect a large number of optical fibers simultaneously and with high precision.

In recent years, various optical fiber transmission systems have been actively studied.

Along with this, the importance of optical fiber connections is becoming more and more important.

Conventionally, many methods have been proposed and prototyped for single-fiber optical fiber connectors, and each method has achieved some success.

On the other hand, as for multi-fiber optical fiber connectors that can connect a large number of optical fibers at once and are detachable, there is currently no study of single-fiber optical fiber connectors. .

In conventional multi-fiber connectors for optical fibers, after setting and fixing a large number of optical fibers on grooves made in parallel at regular intervals, one of the optical fibers is connected to a conventional single-fiber connector. There is a method in which the connectors are centered in the same way as fiber connectors and inserted into a cylindrical aligner, or a method in which a plurality of single optical fiber connectors are assembled in the same housing.

However, all of these have problems such as large external dimensions and poor centering accuracy.

In order to solve these problems, the inventors of the present invention proposed a method for forming optical fibers by anisotropic etching on a silicon substrate in Japanese Patent Application No. 54-009076 (Japanese Unexamined Patent Publication No. 55-101904). We have proposed a multi-core optical fiber connector in which a groove is formed and a knock pin positioned with high precision is butted against the V-groove.

However, in the above proposal, considerable skill was required to position the dowel pin, and at this stage, there remained problems such as a positional error of the dowel pin with respect to the groove.

In addition, the above proposal also mentions forming ■grooves for setting dowel pins on the silicon substrate on which ■grooves for fiber setting are formed, but forming ■grooves with a depth of several mm. Etching time is 1 because it is necessary.
In addition, during such long etching times, accidents such as peeling of the etching mask often occur, and there are manufacturing problems such as the inability to form grooves of a predetermined shape. Ta.

An object of the present invention is to solve the problems with the prior art described above, and to reduce the amount of anisotropic etching required.
An object of the present invention is to provide a multi-core optical fiber connector that enables shortening of etching time and improvement of product yield rate.

A feature of the present invention is that, in order to achieve the above object, a large number of parallel grooves for optical fiber mounts and grooves for dowel pin mounts positioned parallel to these grooves are formed by anisotropic etching. Two plugs with the same structure are formed by holding a dowel pin in a dowel pin mounting groove on a silicon substrate, inserting an optical fiber into each of the optical fiber mount grooves, and terminating one end thereof, and a splitter for inserting the dowel pin. In a multi-fiber optical fiber connector consisting of one adapter with a sleeve, the dowel pin mounting groove is formed by anisotropic etching on the top surface of the silicon substrate to form a groove with an inverted isosceles trapezoidal cross section, and the bottom surface of the groove is formed on the bottom surface of the silicon substrate. When the trench is formed to reach the bottom surface of the silicon substrate or not to reach the lower surface of the silicon substrate to form a through hole, a groove having a diameter larger than the through hole diameter corresponds to the position of the through hole. The formed plate is fixed and integrated with the silicon substrate, and when the groove does not reach the lower surface of the silicon substrate, the bottom surface of the groove is further excavated to a certain degree.

The present invention will be explained below with reference to the drawings.

FIG. 1 is a perspective view for explaining the overall structure of the present invention, in which 1 and 1' are plugs, 2 is an adapter, and 3, 3' and 4, 4' are dowel pins.

The plug 1 and the plug 1' split the dowel pin 3 and the dowel pin 3' into the sleeve 5 via the adapter 2, and
By aligning the knock pin 4 and the knock pin 4' within the split sleeve 6, they are butted and aligned.

FIG. 2 is a cross-sectional view for explaining one embodiment of the present invention, showing a part of the plug 1 (plug 1'), and shows 7-1, 7-2..., 7-n. The optical fibers are respectively set in grooves formed in the silicon substrate by anisotropic etching, and are further pressed from above by an optical fiber holding plate 9 so as to be accurately positioned in the grooves.

Optical fiber 7-1゜7-2. ..., while keeping 7-n, the silicon substrate, and the optical fiber holding plate 9 in this state, apply the adhesive 1.
It is fixed at 0.

On the other hand, dowel pin 11 (3.3' and 4,4 in Fig. 1)
) corresponds to silicon substrate 8 (8-1 part and 8-
The dowel pin is set by pressing it with a dowel pin holding plate 12 so that the dowel pin is in contact with the side wall surface of the through hole formed by anisotropic etching at points A and B (consisting of two parts).

Adhesive 10 is used to maintain and fix this state.

An auxiliary substrate 13 having grooves formed at positions corresponding to the through holes is adhesively fixed to the lower side of the lower surface of the silicon substrate 8.

This is used to prevent separation of portions 8-1 and 8-2 of the silicon substrate, and also to avoid inconveniences caused by the dowel pin 11 being located further below the bottom surface of the silicon substrate, as shown by the hatched area.

Since the grooves and through holes formed in the silicon substrate 8 are formed by an anisotropic etching process, they are formed at predetermined positions with high precision.

Therefore, the plug made using such a board is
As shown in the explanation of the figures, the optical fibers are connected by butt-connecting the dowel pins through the split sleeves.

FIG. 3 is a plan view showing the integration of the silicon substrate 8 and the auxiliary substrate 13 in the case of the plug having the structure shown in FIG. After setting and fixing the silicon substrate 14 so that the through hole of the silicon substrate 14 corresponds to the groove of the auxiliary substrate 13, the silicon substrate 14 is cut along X-X and Y-Y'.

By doing this, 8 of the silicon substrate 8 shown in FIG.
It is possible to prevent separation of the -1 portion and the 8-2 portion and to improve the dimensional accuracy of the through hole.

FIG. 4 is a sectional view showing a comparison between the conventional structure A and the structure B of the first embodiment of the present invention, and the same reference numerals as in FIG. 2 are used.

In the case of conventional structure A, the minimum required etching amount is a = r (1-sin3
5°), where 356 is 1/2 of the apex angle of 70° created by extending the isosceles of the inverted isosceles trapezoid cross section, and the apex angle of 70° is an angle determined crystallographically with respect to the silicon substrate. However, in the case of structure A according to the present invention, the minimum required etching amount is almost zero, and even a thin silicon substrate with a thickness of about 100 μm, for example, can be used.

That is, in conventional structure A, since the minimum required amount of etching is determined depending on the diameter of the dowel pin, it may become virtually impossible to form a groove for mounting the dowel pin.

For example, if we use a dowel pin with a radius r of 2 mm,
The minimum required etching amount is a = 0.86 mm from the above formula, but in the configuration of Example Structure A, the groove for the dowel pin mount can be formed with an etching amount of about 0.1 mm regardless of the diameter of the dowel pin. .

Generally, the amount of etching is smaller in the embodiment structure B than in the conventional structure A by the depth d shown in FIG.

In this way, the fact that the amount of etching is small reduces the etching time, and also reduces the probability of defective products due to peeling off of the etching protective film that occurs during the etching process, in other words, it is possible to improve the yield rate. This has a great effect on manufacturing.

FIG. 5 is a sectional view showing a second embodiment of the present invention.
This is a case where the groove formed for mounting the dowel pin should not reach the bottom surface of the silicon substrate.

That is, after performing anisotropic etching by a depth b that does not reach the bottom surface of the silicon substrate 8, the bottom surface of the groove having an inverted isosceles trapezoid cross section formed on the silicon substrate by this anisotropic etching is further processed by grinding, etc. The method is used to dig down by a depth C.

Even in this case, the required amount of anisotropic etching is
The structure of the second embodiment is the same as that of FIG.

In this case, the groove dug down by grinding etc. is simply to lower the position of the bottom surface so that the dowel pin 11 can be correctly positioned in the groove, so both machining accuracy and surface roughness are highly accurate. It doesn't have to be.

Machining the grooves as shown on the silicon substrate 8 in FIG. 5 from the beginning by grinding without using an anisotropic etching process allows for high precision in all aspects including positional accuracy, dimensional accuracy, and surface roughness. Processing is required and manufacturing difficulties are great.

As explained above, according to the present invention, since the groove for the optical fiber mount and the groove for the dowel pin mount are formed on the silicon substrate by anisotropic etching, high positional accuracy and dimensional accuracy can be achieved. Grooves with high precision and surface roughness can be formed, and in the case of grooves for dowel pin mounts, drilling down to reach the bottom surface of the silicon substrate to form through holes, or drilling down to a predetermined depth. When the bottom surface of the groove is then dug down by grinding, etc., the amount of anisotropic etching is very small regardless of the diameter of the dowel pin, which reduces the etching time and prevents the etching protection film from peeling off during the etching process. This has significant advantages in terms of manufacturing, such as a reduction in the number of defective products caused by this, that is, an improvement in yield rate.

[Brief explanation of drawings]

FIG. 1 is a perspective view illustrating the overall configuration of the present invention, FIG. 2 is a sectional view showing the first embodiment of the present invention, and FIG. 3 is a plan view illustrating the production of a plug having the structure shown in FIG. FIG. 4 is a sectional view for explaining a comparison between the conventional structure and the structure of the first embodiment, and FIG. 5 is a sectional view showing the second embodiment of the present invention. Explanation of symbols, 1, 1'...Plug, 2...Adapter, 3
, 3', 4, 4'... Dowel pin, 5, 6... Split sleeve, 7-1, 7-2. 7-n... Optical fiber, 8.8-1.8-2... Silicon substrate, 9... Optical fiber holding plate, 10... Adhesive, 11... Knock pin, 1
2... Knock pin presser plate, 13... Auxiliary board, 14...
Silicon substrate with through holes and grooves.

Claims (1)

[Claims] 1 Multiple parallel ■grooves for optical fiber mount and this■
A dowel pin is held in the dowel pin mount groove of the silicon substrate, in which a dowel pin mount groove positioned parallel to the groove is formed by anisotropic etching, and an optical fiber is inserted into each of the optical fiber mount grooves. It consists of two plugs with the same structure formed by terminating one end and an adapter having a split sleeve for inserting the knock pin, and by butting the two plugs together via the adapter, a large number of optical fibers can be connected simultaneously. In multi-fiber optical fiber connectors, the groove for dowel pin mounting is formed by anisotropic etching on the top surface of the silicon substrate as a groove with an inverted isosceles trapezoidal cross section so that the bottom surface of the groove reaches or does not reach the bottom surface of the silicon substrate. When the groove is formed and the groove reaches the bottom surface of the silicon substrate to form a through hole, a plate having a hole diameter larger than the diameter of the through hole is formed corresponding to the position of the through hole. A multi-core optical fiber connector, characterized in that the bottom surface of the trench is further dug to a certain depth when the trench does not reach the bottom surface of the silicon substrate.