JPS6219365A - Optical fiber polishing of convex spherical tip connector - Google Patents

Abstract

PURPOSE:To realize high accuracy optical fiber polishing of a convex spherical tip connector by using a polymer sheet, on which a polishing material having polishing effect on both optical fiber and glue but having no polishing effect on ceramics, glued on a polishing disk. CONSTITUTION:The bottom end of a ferrule 1 held by a holder is pressed against a lapping film 10 glued on a polishing disk 7. The lapping film 10 consists of a polymer sheet 10a and a polishing material 10b firmly glued on the polymer sheet 10a and having polishing effect on both an optical fiber F and glue 6' but having no polishing effect on a ceramic cylinder 5. The lapping film 10, having some degree of elasticity, when pushed by the convex spherical surface 2 of the ferrule 1, recedes and makes a convex spherical surface according to the convex surface. Accordingly, only the glue 6' and the tip of the optical fiber F' are polished with the convex spherical surface 2 being as a guide. This makes it possible to use a plane polishing machine and moreover the polishing accuracy can be enhanced.

Description

DETAILED DESCRIPTION OF THE INVENTION "Field of Industrial Application" The present invention relates to an optical fiber connector for connecting optical fibers, and is a novel method for polishing the tip of an optical fiber that is passed through a convex spherical tip connector.

``Prior art and problems'' In conventional optical fiber connectors, an optical fiber χ is passed through a small hole drilled in the core of a part called a ferrule and fixed with adhesive, and then the tip of the ferrule is attached to the optical fiber. It is polished to a flat surface (approximately 0, 1, P) integrally with the tip surface. In addition, when the connector is connected and disconnected many times, it is necessary to prevent the connection loss of the optical fiber from increasing gradually.
Only the end face of the optical fiber was finished in a concave shape. This method has the disadvantage that the splice loss is large from the beginning, and as a solution to this problem, it has been known for a long time that the splice loss can be reduced by closely splicing the end faces of two optical fibers. 7 rules as shown in Figure 2 1 Convex convex spherical surface 2
As shown in Fig. 2 (b), a connector 100 machined into a connector 100 has been developed, which has a small hole 3 in the center and a ceramic cylindrical body 5 on its outer periphery (the small hole 3 is made in the ceramic). It is covered with a stainless steel cylindrical body 4. Of course, there are also ferrules in which the stainless steel cylinder body 4 is omitted. As shown above, the tip is convex. □When passing the optical fiber together with the adhesive 6 through the small hole 3 of the ferrule 1 machined into the spherical surface 2, the tip F'Y of the optical fiber protrudes a small amount from the convex spherical surface 2 and the adhesive It is also necessary to raise it like 6'.

In order to polish the tip end surface of the convex spherical surface 2 of such a ferrule 1, a convex spherical surface processing and polishing machine is required to process the convex spherical surface 2 before passing the optical fiber therethrough. However, for general users, although there are polishing machines that polish the end face of an optical fiber to a flat surface, there is no polishing machine that polishes the end face of an optical fiber to a convex spherical surface, and it is necessary to purchase a new convex spherical polishing machine. An unavoidable problem has occurred.

``Means for Solving the Problem 1 Effect'' The present invention has been developed in view of the above-mentioned problems, and provides a novel method that enables polishing of an optical fiber passed through a convex spherical ferrule even with a conventional polishing machine for flat surfaces. The purpose of this paper is to provide a polishing method that is suitable for polishing.

That is, fixed abrasive grains are formed by bonding abrasive materials (abrasive grains) such as aluminum oxide and oxidized particles, which have the ability to grind optical fibers and adhesives but have poor ability to grind ceramics, to the surface of a resin sheet such as polyester. The most protruding part of the convex spherical surface is created by attaching a polishing sheet (hereinafter referred to as lapping film) on the polishing disk, and the synergistic effect of the cushioning property of the lapping film and the non-abrasive property for ceramics allows the most protruding part of the convex spherical surface to be We succeeded in polishing the optical fiber end face to a convex spherical surface of the same shape as the convex spherical surface of the ceramic adhesive and the convex spherical surface of the ceramic adhesive. Only the end face of the optical fiber can be made flat or polished into a concave surface.

"Example" Hereinafter, an optical fiber polishing method for a connector with a convex spherical tip according to the present invention will be described with reference to embodiments shown in the drawings. First, as shown in FIG.
The optical fiber tip F' and the adhesive 6' are attached to the central protrusion of the convex spherical surface 2 in a protruding manner. After the adhesive 6.6' has dried, hold it in a holder (not shown) as shown in Figure 1.
The ferrule 1 is pressed against the wrapping film 10 stuck on the polishing disk 7 by a predetermined weight at its lower end (two convex spherical tips 6/, F/). The wrapping film 10 has a thickness of, for example, about several tens of microns to 100 microns.
An optical fiber (quartz-based, multicomponent-based, plastic-based, etc.) 2 is attached to the surface of a resin sheet 10α made of polyester, etc.
The abrasive grains 10b (aluminum oxide, chromium oxide, silicon carbide, etc.), which have the ability to polish the ceramic cylinder 5 but have the ability to polish the adhesive 6', are used as abrasive grains, and the adhesive 6' is made of polyester. The abrasive particles are fixed to the resin sheet as fixed abrasive grains.

Since the above-mentioned wrapping film 10 has a slight cushioning property, it is pressed against the convex spherical surface 2 of the ferrule and becomes depressed, as shown in FIG. Therefore, when the disk 7 is rotated by the shaft 8 (a crankshaft with an eccentric width of X) shown in FIG. 1, the state shown in FIG. Only the adhesive 6' adhering to the optical fiber and the tip F' of the optical fiber are polished as a convex spherical surface 2t guide. The above-mentioned polishing is performed over several steps of roughing, medium and finishing n1, and since the disc 7 undergoes eccentric and rotational movement T, the surface of the wrapping film 100 is guided by the convex spherical surface 2 from each direction with respect to the ferrule 1. Every time it runs, polishing can be performed with high precision and uniformity equal to the radius of curvature of a convex spherical surface.

Next, modified polishing examples are shown in FIGS. 4(b) and 4(c).

First, in FIG. 4(b), the tip end surface 6' of the optical fiber 6 is made into a flat surface by, for example, taking a sufficient amount of time for final polishing. In FIG. 4() and 4, the tip end surface 61x of the optical fiber 6 is made into a concave shape by buffing in the final step.

In any of the shapes shown in FIGS. 4(a) to 4(c), the finishing of the optical fiber end surface can be freely changed depending on the user's needs.

"Effect" In the case of non-invention, since the method was based on timely polishing of a lapping film that has cushioning properties for the convex spherical ferrule and is non-abrasive for ceramics, it is possible to use a polishing machine that can only polish ordinary flat surfaces. Not only is it possible to polish the adhesive attached to the tip of the convex spherical surface and the tip surface of the optical fiber, but the convex spherical ceramic of the non-polishing layer acts as a guide, and the radius of curvature is the same as that of the convex spherical surface of the ceramic. This has the effect of allowing precise polishing. Furthermore, if necessary, it is also possible to make only the end face of the optical fiber a flat surface.

[Brief explanation of drawings]

Figure 1 is a side view of a ferrule and polishing disk showing the method of implementing the present invention, Figure 2 is a side view and enlarged sectional view of a convex spherical ferrule, and Figure 3 is an optical fiber and adhesive passed through the convex spherical ferrule. FIG. 4 is a sectional view before polishing showing the relationship between the optical fiber and the polishing shape. 1...Ferrule, 2...Convex spherical surface, 3...Small hole,
4. Stainless steel cylinder body, 5. Bone ceramic cylinder body,
6.6'...Adhesive, F, F'...Optical fiber, 7
... Polishing disc, 10'' wrapping film (polishing sheet), 100... Connector.

Claims (1)

[Claims] A connector with a convex spherical tip that has cushioning properties for the optical fiber and adhesive passed through a ferrule with a convex spherical tip, and which is characterized by polishing the convex spherical ceramic of the ferrule for an appropriate amount of time with a non-abrasive wrapping film. optical fiber polishing method.