JPH07124855A - Working method for ferrule for optical connector - Google Patents

Abstract

PURPOSE:To lessen loss in connection by letting ferrules which agree with each other at each apex, be butted against each other. CONSTITUTION:The tip end of a ferrule 1 for an optical connector, at the center of which a fine hole 5 is bored, is tapered comvergently, the tip end face is formed into a spherical surface thereafter, the tip end face is tilted by an angle of theta with respect to the surface perpendicularly intersected with the axial line 5a of the fine hole, and a tapered angle is increased/decreased within a range of (-theta to +theta), so that the apex of the spherical surface thereby agrees with the fine hole 5.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in a method for processing a ferrule for optical connector.

[0002]

2. Description of the Related Art Optical fibers are connected by optical connectors.
FIG. 6 is a cut view of a ceramic ferrule. A ceramic ferrule formed by firing a ceramic into a cylindrical shape and fired is referred to as a ceramic ferrule 100 (hereinafter, abbreviated as “ferrule”). A hole 101 for fixing through is provided, and a flange 102 made of metal or the like is provided. Connection is spherical surface 10 at the tip
It is carried out by abutting the three, but the light is spherical 103
Causes a slight reflection, resulting in a connection loss.

Therefore, as a technique for preventing loss due to reflection, Japanese Patent Laid-Open No. 63-279205 and Japanese Patent Laid-Open No. 1-1218 have been proposed.
No. 05 proposes that the tip of the ferrule be an inclined surface. 7 (a) to 7 (c) are explanatory views of a method of processing a conventional inclined surface type ferrule. JP-A-1-12180
No. 5 describes that (c) is cut out from (a) using a polishing jig, but (b) is generally used as an intermediary.

That is, in (a), the tip of the ferrule 201 is a surface perpendicular to the fiber 202. Then, the tip is cut at an angle θ in (b). Next, the cut surface 201a is polished and finished to obtain a spherical surface 201b. This (c) corresponds to the tip shape of the ferrule of JP-A-63-279205 and JP-A-1-121805.

[0005]

FIG. 8 is an enlarged view of FIG. 7 (c). The spherical surface 201b is formed with the cut surface 201a as a tangent line, so that the apex 201c of the spherical surface is drawn out from the center of the fiber 202 at an angle θ. It is tied to the intersection with the marked line. The apex 201c will be offset from the fiber 202 by a dimension δ. If ferrules whose vertices are offset from each other are abutted against each other, the adhesion will naturally deteriorate and a connection loss will occur.

Therefore, an object of the present invention is to provide a processing method capable of matching the apex of a spherical surface with a fiber.

[0007]

SUMMARY OF THE INVENTION To achieve the above object, the present invention is to taper the tip of an optical connector ferrule having a hole at the center, and then taper the tip surface. did. In addition, the tip surface is inclined at an angle θ with respect to the plane perpendicular to the pore axis line, and the taper angle is correspondingly increased or decreased in the range of (−θ to + θ) to match the apex of the spherical surface with the pore. did.

[0008]

Embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a sectional view of a ferrule manufactured by the method of the present invention. A ceramic ferrule 1 (hereinafter abbreviated as “ferrule”) is first formed with a tapered taper surface 2, and a spherical surface 3 is formed at the tip thereof. And the apex 4 thereof coincides with the axis 5a of the pore 5.

The taper angles α, α are determined in the following geometrical description. A sphere 3 passing through the apex 4 (sphere radius R is known) is drawn to define intersections 7 and 8 with the chord 6, and these intersections 7 and 8 are defined.
The diagonal lines 11 and 12 (corresponding to the isosceles hypotenuse of the isosceles triangle) may be drawn. As a result, the tapered surface 2 in the upper part of the figure is (α + θ) with respect to the pores 5, and that of the lower part is (α−θ).

A processing method for obtaining the ferrule having the above shape will be described below. 2A to 2D are explanatory views of a processing method according to the method of the present invention. First, the ferrule 1 having the tip of FIG. The taper processing method will be described later in detail.

In step (c), an inclined surface 14 having an inclination angle θ is formed at the tip. At this time, since the processing center and the pore 5 coincide with each other, the apex 4 of the spherical surface 3 is formed at the same position as the pore. Spherical processing is performed in (d). (D) is the same as FIG.

FIGS. 3 (a) to 3 (d) are explanatory views of a processing method according to another method of the present invention. In FIG. 3 (b), the inclined surface 14 is first formed at the tip, and then in FIG. 3 (c), taper processing is performed. The result is the same as that of FIG. 2 (d).

FIG. 4 is a principle view of a processing apparatus suitable for carrying out the method of the present invention. The processing apparatus 20 holds a chuck 21 for gripping the ferrule 1 and fixing it to a rotating spindle (not shown), and a tip side of the ferrule. And a polishing machine 22 for polishing. The ferrule 1 has a rotation center 21 of the chuck 21.
It is attached at an angle of θ with respect to a.

The ferrule 1 is shown in FIGS. 2 (a) to 2 (d).
First, (a) the ferrule whose tip is perpendicular to the pore axis is gripped by the chuck 21,
(B) While being rotated, taper processing is performed by the polishing machine 22, (c) the inclined surface 14 is formed, and (d) the point on the inclined surface where the rotation center 21a and the axis 5a of the pore 5 coincide with each other is a vertex. A spherical surface is processed as 4. This is shown in Fig. 3.
A processing procedure according to another method according to (a) to (d) may be used.

FIG. 5 is a principle diagram of another processing apparatus for carrying out the method of the present invention. In this processing apparatus 30, the ferrule 1 is used.
However, the chuck 31 is mounted eccentric to the rotation center 31a of the chuck 31 by a distance m. 32 is a polishing machine. In this case, the inclination angle θ of the inclined surface 14 and the spherical radius R of the spherical surface 3
Considering (see FIG. 1), the distance m is determined so that the spherical surface and the axis 5a of the pore 5 are close to each other. Figure 4 above
Since the ferrule 1 is attached in parallel with the rotation center 31a, the attachment structure of the chuck 31 is simpler than that of the processing apparatus 20 of FIG.

The taper process is not limited to polishing, and it may be formed integrally with the tip of the ferrule 1 by injection molding or press molding.

[0017]

As described above, according to the present invention, the tip of the ferrule for an optical connector, which has a hole in the center thereof, is tapered at the tip, and then the tip surface is made spherical. The positional deviation between the apex and the fiber can be reduced, and the connection loss at the butting portion of the ferrules can be reduced.

Further, the tip surface is inclined at an angle θ with respect to the plane perpendicular to the pore axis line, and the taper angle is correspondingly (−θ
.About. +. Theta.) To increase or decrease in order to match the apex of the spherical surface with the pores, but the ferrules whose apex coincides with each other can be brought into contact with each other to further reduce the connection loss.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a ferrule manufactured by the method of the present invention.

FIG. 2 is an explanatory view of a processing method according to the method of the present invention.

FIG. 3 is an explanatory view of a processing method according to another method of the present invention.

FIG. 4 is a principle diagram of a processing apparatus for carrying out the method of the present invention.

FIG. 5: Principle diagram of another processing apparatus for carrying out the method of the present invention

[Figure 6] Cut view of the ceramic ferrule

FIG. 7 is an explanatory view of a method for processing a conventional inclined surface type ferrule.

8 is an enlarged cross-sectional view of the ferrule by the processing method of FIG.

[Explanation of symbols]

1 ... Ferrule, 2 ... Tapered taper surface, 3 ... Spherical surface, 4 ...
Apex, 5 ... Pore, 14 ... Inclined surface.

Front page continuation (72) Inventor Morinoyuki Fujitake 2-1-1 Nakajima, Kokurakita-ku, Kitakyushu, Fukuoka Totoki Equipment Co., Ltd. (72) Eiichi Tanaka 2-chome, Nakajima, Kitakyushu, Kitakyushu, Fukuoka No. 1 No. 1 Totoki Equipment Co., Ltd.

Claims (2)

[Claims] 1. A method of processing a ferrule for an optical connector, characterized in that a tip of the ferrule for an optical connector having a small hole in the center thereof is tapered and tapered, and then the tip surface is spherically processed. 2. The tip surface is inclined at an angle θ with respect to the plane perpendicular to the pore axis line, and the taper angle is (−) correspondingly.
2. The method of processing a ferrule for an optical connector according to claim 1, wherein the apex of the spherical surface is made to coincide with the pore by increasing or decreasing in the range of θ to + θ).