JPH1086052A - Polishing method for optical fiber connector - Google Patents

Abstract

PROBLEM TO BE SOLVED: To remarkably increase grinding efficiency and drastically decrease occurrence of polishing flaws by adding an ultrasonic generator and a vibrator and applying ultrasonic energy on either one of an optical fiber connector or a polishing board side or the both so as to polish it. SOLUTION: A polishing work is so implemented that ultrasonic wave is generated by an ultrasonic generator 18 and a vibrator 17, ultrasonic energy is applied on a polishing jig 13, an appropriate load P is applied thereon within a range from approximately 0.1g to 100g, and the polishing jig 13 having an optical fiber connector 15 set therein is pushed against a polishing board 11. While the polishing board 11 is slowly rotated by a motor 10, the polishing board 11 is planetary rotated around a shaft 21. Polishing liquid composed of water, oil, and other components is dropped thereon to improve dispersion of abrasive grain and polishing waste.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polishing method for polishing an end face of an optical fiber connector in which an optical fiber and a ferrule are connected.

[0002]

2. Description of the Related Art As a conventional method for polishing an end face of an optical fiber connector in which an optical fiber and a ferrule are connected, a polishing method using so-called fixed abrasive grains, which uses an abrasive body having abrasive grains fixed thereto, is known. Have been. As the polishing body, a polishing sheet in which abrasive grains are fixed to a paper or a plastic sheet, or a rotary grindstone in which diamond abrasive grains are bonded by an adhesive is used. This polishing method will be briefly described with reference to FIG. As shown in the figure, first, the optical fiber 1 is inserted into the ferrule 2, and an adhesive 5 is applied to fix the optical fiber 1 to the ferrule 2. Optical fiber connector 1 composed of this integrated optical fiber and ferrule
5 is fixed to the holding tool 54 with the fixing engagement nut 55, and then the polishing tool is pressed onto a surface plate 57 on which the polishing sheet 12 is stuck, and the holding tool is moved to polish the surface.
A method has been used in which one or both of the tool and the holding tool 54 are rotated for polishing. In addition, FIG.
As shown in FIG. 1, there is known a method in which an optical fiber connector 15 in which an optical fiber 1 and a ferrule 2 are connected is pressed against a rotating grindstone 30, and one or both of the rotating grindstone 30 and the optical fiber connector 15 are rotated to perform polishing. ing.

Next, another polishing method will be described with reference to FIG. As shown in the figure, a polishing liquid 20 mixed with abrasive grains such as diamond, silicon oxide, chromium oxide, aluminum oxide, and cerium oxide is applied onto a polishing body 63 such as a buff or a plastic sheet. There is known a method of rotating and polishing one or both of the optical fiber connectors 15 which are a combined body of the optical fiber 1 and the ferrule 2 as a workpiece. Generally, this method is referred to as a polishing method using loose abrasives because polishing is performed in a state where the abrasive grains are not fixed to the polishing body 63 such as a puff.

[0004]

First, the problems of the above-described conventional method will be briefly described with reference to FIGS. 8 and 9. FIG. FIG. 8 is an enlarged view of a distal end portion of an optical fiber connector 15 which is a combined body of the optical fiber 1 and the ferrule 2. As shown in the figure, the state of the tip portion of the normal optical fiber connector 15 before polishing is such that the optical fiber 1 into which the adhesive 5 is attached and which is inserted protrudes. On the other hand, as described above, the conventional polishing method uses the optical fiber connector 15 and the polishing sheet 12.
In this method, the polishing is performed by rotating the surface plate or the like on which the polishing sheet 12 is stuck in a fixed direction. For this reason, as shown in the figure, when the polishing sheet 12 is moving in the direction of the arrow A in the figure, the optical fiber tip 73 is bent in the direction of the arrow B in the figure due to frictional resistance generated during polishing. The force to be applied acts. For this reason, as shown in FIG. 9, the optical fiber tip 73 falls off, and a defect 74 occurs. When chipping or scratching of the optical fiber occurs, as is well known, when a pair of optical connectors are brought into contact with each other, the contact surfaces do not completely come into surface contact with each other, so that there is a problem that optical coupling loss increases. For this reason, when polishing, the pressing load should be as small as possible, and the bending moment force should not be applied to the optical fiber tip portion 73, or the bending moment force should be reduced to the optical fiber tip portion 7.
A polishing method that can polish while keeping the number 3 below such that it does not break is desired. An object of the present invention is to solve the above-mentioned problems and to provide a polishing method in which a protruding polishing portion does not fall off.

Next, another problem will be described with reference to FIG. As shown in the figure, on the surface of the polished surface, polishing debris 7 composed of abrasive grains detached from the polishing sheet 12, a ground adhesive, an optical fiber, and a ferrule is provided.
6 remain. If these polishing scraps 76 remain, and remain in a state of being biased without being particularly dispersed,
There is a problem that a deep polishing flaw is locally generated on the polished surface of the optical fiber. Another object of the present invention is to provide a polishing method for positively dispersing the above-described polishing waste 76 from a polished portion and polishing the polished surface so that scratches on the polished surface are minimized.

Another problem which is likely to occur particularly in a method of polishing using fixed abrasive grains will be described. The polishing method using fixed abrasive grains is characterized by high grinding power and good processing efficiency, but the pressing force against the workpiece is large, and the pressing force changes due to unevenness and undulation of the polishing plate. I do. For this reason, there has been a problem that the polished portion of the optical fiber is broken due to brittle fracture, and polishing scratches are generated on the polished surface of the optical fiber. The best way to solve this problem is to carry out polishing with the polishing load as small as possible while keeping the polishing efficiency equal to or higher than that of the conventional method. It is another object of the present invention to provide these methods.

[0007] In addition, there is a problem particularly in the conventional method of polishing with free abrasive grains. Ferrule materials include ceramics and metals such as aluminum oxide or zirconia,
Plastics, etc., and quartz for optical fiber materials
In most cases, glass, plastic, or the like is used in a combination in which the hardness of the optical fiber and the hardness of the ferrule are significantly different. For this reason, the softer one is polished more, and a step occurs between the fiber end face and the ferrule end face,
As described above, when these are brought into contact with each other, the fibers do not completely adhere to each other, which causes an increase in optical coupling loss. Another problem in polishing using free abrasive grains is that the abrasive grains are poorly dispersed and aggregate in the polishing solution. When such agglomeration occurs, the organization in which the polishing liquid is used is short, and when the agglomerated abrasive grains act on the processed surface of the optical fiber, a scratch or a large scratch is locally left and an altered layer is easily generated. Another object of the present invention is to solve the above-mentioned problems and to provide a polishing method in which an optical fiber and a ferrule are uniformly polished and aggregation of polishing abrasive grains in a polishing liquid is prevented to prevent polishing scratches. Is to do. The above-mentioned problems have been described by taking as an example the case of a combination of a single-core optical fiber and a ferrule.However, these problems are caused by polishing an optical fiber connector in which a tape-shaped multi-core optical fiber and a ferrule are coupled. Also occurs.

[0008]

In order to achieve the above object, an end face of an optical fiber connector comprising a ferrule and an optical fiber is placed on a polishing plate to which a polishing sheet is attached in the case of a fixed abrasive polishing method. In addition, in the case of the free abrasive polishing method, a polishing liquid is pressed onto a polishing plate in which a polishing liquid is dispersed, and in addition to the rotational movement of one or both of the polishing plate and the optical fiber connector, the end face of the optical fiber connector is The conventional method of mirror polishing is characterized in that an ultrasonic oscillator and a vibrator are added, and polishing is performed by applying ultrasonic energy to one or both of the optical fiber connector and the polishing plate.

Generally, in a machining method using ultrasonic waves, abrasive energy having a sharp angle interposed between a tool and a workpiece is formed by applying ultrasonic energy to a machining liquid and abrasive grains. It is driven into the workpiece by vibration, and a large machining capacity can be obtained with a small contact area. Thereby, it is said that the surface finishing accuracy of the processed surface is improved, the processing resistance is significantly reduced, and the processing speed is greatly increased. It is well known that when ultrasonic waves are propagated in a liquid, the liquid and substances in the liquid cause micro-vibration, stirring, and defoaming phenomena in addition to the cavitation action of the liquid itself.

In the case of the polishing method of the present invention in which the end face of the optical fiber connector is polished by applying ultrasonic energy to the polished portion, the frictional resistance generated between the polished surface of the optical fiber connector and the polishing plate during polishing. Is greatly reduced. Further, in the conventional method, this frictional resistance only acts in a fixed direction, but in the method of the present invention, in addition to the frictional resistance in the fixed direction, the frictional direction changes in the phase direction at a very high speed of tens of thousands of times per second. A phase friction resistance is generated, and the phase friction resistance becomes dominant. In addition, the amplitude of the reciprocating motion is several μm to several tens μm, which is very small. Therefore, the bending moment force on the protruding portion of the polished portion of the optical fiber connector, which causes the optical fiber to be broken, is greatly reduced.

In the case of the polishing method of the present invention using free abrasive grains, since the abrasive grains are uniformly dispersed over the entire polished surface by ultrasonic energy, the polishing force of the abrasive grains on the fiber polished surface is also reduced. Become uniform. Further, ultrasonic energy is transmitted to the polishing liquid, and the effect of dispersing and discharging polishing waste from the polished surface is also obtained, so that agglomeration of abrasive grains and polishing waste causing scratches and defects does not occur. In the case of the fixed abrasive polishing method, the same effect can be obtained by dropping the polishing liquid.

[0012]

In the polishing method of the present invention, ultrasonic energy is generated using an ultrasonic oscillator and an ultrasonic vibrator, and the ultrasonic energy is applied to an optical fiber connector or a polishing plate as a workpiece. A means for applying is provided.

It is preferable that the vibrator be integrated with a polishing jig to which an optical fiber connector is fixed so that ultrasonic energy is efficiently transmitted to a polishing portion.

An embodiment of the present invention will be described with reference to the drawings. First, the configuration of the combined optical fiber and ferrule to be polished by the polishing method of the present invention will be described. FIG. 1 is a sectional view showing an optical fiber connector of a combined body of an optical fiber and a ferrule. Quartz glass as shown in the figure,
An optical fiber 1 made of a material such as plastic is inserted into a hole 3 of a ferrule 2 made of ceramic, metal or plastic, and an adhesive 5 is applied to a protruding portion 4 to fix the optical fiber 1 and the ferrule 2 together. ing. As another method of fixing the optical fiber to the metal ferrule, there is a method of fixing the optical fiber insertion portion 6 of the ferrule 2 by compressing and deforming it with a tool (not shown). FIG.
FIG. 4 is a cross-sectional view showing another configuration of the combined body of the optical fiber and the ferrule. As shown in the figure, a bare portion 8 of a tape-shaped multi-core optical fiber cable 7 in which four optical fibers 1 are arranged and integrated is inserted into a ferrule 9 and an adhesive 5
To the ferrule 9. It goes without saying that the multi-core optical fiber cable 7 in the figure has a number of cores of 4 or more.

The method of polishing the optical coupling surface of the optical fiber / ferrule combination thus obtained will be described below. FIG. 3 is a schematic diagram showing one embodiment of the present invention when polishing with fixed abrasive grains. As shown, the polishing plate 11 connected to the motor 10 and the gear transmission mechanism 19
A polishing sheet 12 is stuck on the top. On the other hand, an optical fiber connector 15 which is a combined body of the optical fiber 1 and the ferrule 2 is inserted into the polishing jig 13 and
6. Polishing jig 13 includes vibrator 17
The vibrator 17 is connected to an ultrasonic oscillator 18. In the polishing operation, an ultrasonic wave is generated by the ultrasonic oscillator 18 and the vibrator 17 to apply ultrasonic energy to the polishing jig 13, and as shown in FIG. And the polishing jig 13 on which the optical fiber connector 15 is set is moved to the polishing plate 1.
1 and slowly rotating the polishing plate 11 by the motor 10 while rotating the polishing plate 11 about the shaft 21.
Is performed in a planetary motion. Further, in order to improve the dispersion of the abrasive grains and polishing debris, a polishing liquid containing water, oil, and other components (not shown) may be dropped.

Next, another embodiment of the present invention will be described with reference to FIG. FIG. 4 is a schematic diagram showing an embodiment in the case of polishing using free abrasive grains. As shown in the figure, a polishing liquid 20 is dropped on a polishing plate 11 connected to a motor 10 and a gear transmission mechanism 19, and an optical fiber connector 15 is fixed to a polishing jig 13 by a fixing bracket 16. Further, the polishing jig 13 is integrated with the vibrator 17, and the vibrator 17 is connected to an ultrasonic oscillator 18. The polishing operation is performed by applying ultrasonic energy to the polishing jig 13, pressing the optical fiber connector 15 onto the polishing plate 11, and rotating the polishing plate 11 while dripping the polishing liquid 20.
Moreover, it is performed by planetary motion. When the tip portion of the optical fiber connector 15 is polished into a round shape, polishing is performed using a polishing plate 64 having a polishing body 63 as shown in FIG. 7 instead of the polishing plate shown in FIG.

Another embodiment of the present invention will be described with reference to FIG. FIG. 5 is a schematic view showing an embodiment of the present invention in a case where polishing is performed using a rotary grindstone as a polishing means. As shown, the optical fiber connector 15 is inserted into and fixed to a polishing jig 13 integrated with the vibrator 17. The vibrator 17 is connected to an ultrasonic oscillator 18, an ultrasonic wave is oscillated by the ultrasonic oscillator 18, and ultrasonic energy is applied to the polishing jig 13. On the other hand, the polishing surface 31 of the rotary grindstone 30 connected to a motor (not shown)
Are positioned so that the polished portion 32 of the optical fiber connector 15 is polished.
, The polishing liquid 33 is dropped.
The polishing operation is performed while applying ultrasonic waves to the polishing jig 13.
Feed grinding is performed in the direction of arrow A while rotating the grindstone 30. In this embodiment, the method of applying ultrasonic energy to the polishing jig has been described. However, as another configuration, ultrasonic energy may be applied to the rotating grindstone. Further, the present invention may be implemented as a portable polishing machine by adding a battery power supply to all the above-described configurations.

[0018]

As is apparent from the above description, according to the present invention, since the polishing can be performed while the ultrasonic energy is always applied to the polished portion, the grinding efficiency is significantly increased. Further, when polishing using fixed abrasive grains, the magnitude of the load pressing the optical fiber connector against the polishing plate is usually about several tens gw / mm ² , but according to the present invention, the magnitude of the load is reduced by the conventional number. In this case, the polishing rate is higher than that of the conventional method. Therefore, the occurrence of polishing scratches is greatly reduced as compared with the conventional method.

In the case of a polishing method using free abrasive grains,
The ultrasonic energy propagates to the polishing liquid, and the abrasive grains collide with the surface to be processed with a large impact force, thereby increasing the grinding effect. Furthermore, in the conventional method, since the polishing is performed on the polishing plate rotating in one direction, a frictional force acts in one direction, whereas in the case of the present invention, the grinding is mainly performed by ultrasonic vibration. The frictional force applied to the polished portion of the optical fiber acts only as a small reciprocating frictional force. For this reason, a moment force in a certain direction, which causes the optical fiber polished portion to fall off, does not act, and the occurrence of polishing scratches and chips on the polished surface of the optical fiber is significantly reduced as compared with the conventional method and hardly occurs. In addition, since this minute reciprocating movement is performed at a high speed of several tens of thousands of times per second, even in the case of the polishing method using loose abrasive particles, the polishing state is close to the state of polishing with fixed abrasive particles, and the set of workpieces is polished. Even if there is a considerable difference in hardness, no great difference occurs in the polishing amount. As another effect in the case of the polishing method of the present invention further using free abrasive grains, ultrasonic energy is transmitted to the polishing liquid,
Abrasive grains and polishing debris are dispersed, and there is an advantage that polishing scratches due to aggregation of the abrasive grains and polishing debris are eliminated and the polished surface is uniformly polished. The same effect can be obtained by dropping the polishing liquid even in the embodiment of the present invention of the polishing method using fixed abrasive grains.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a configuration of an optical fiber and a ferrule according to the present invention.

FIG. 2 is a plan view showing a configuration of another optical fiber and a ferrule according to the present invention.

FIG. 3 is a schematic view showing one embodiment of the present invention of a method of polishing with fixed abrasive grains.

FIG. 4 is a schematic view showing one embodiment of the present invention in the case of polishing using free abrasive grains.

FIG. 5 is a schematic view showing one embodiment of the present invention in a case where polishing is performed using a rotary grindstone as a polishing means.

FIG. 6 is a plan view including a sectional view showing a conventional method of polishing using fixed abrasive grains.

FIG. 7 is a cross-sectional view showing a conventional method of polishing using free abrasive grains.

FIG. 8 is an enlarged cross-sectional view of a distal end portion of an optical fiber connector which is a combined body of an optical fiber and a ferrule.

FIG. 9 is a cross-sectional view showing, in an enlarged manner, a distal end portion of the optical fiber connector before and after a defect occurs, according to the conventional method.

FIG. 10 is a cross-sectional view illustrating a polished portion in an enlarged manner according to a conventional method.

[Description of Signs] 1 Optical fiber 2, 9 Ferrule 5 Adhesive 11, 64 Polishing plate 12 Polishing sheet 13, 27 Polishing jig 15 Optical fiber connector 17 Transducer 18 Ultrasonic oscillator 20, 33 Polishing liquid 30 Rotating grindstone 57 Board 63 Polished body 74 Missing part 76 Polishing waste

Claims (1)

[Claims] 1. A polishing method for polishing an end face of a combination of an optical fiber and a ferrule on a polishing plate, wherein the combination or the polishing plate is polished by applying ultrasonic energy. Polishing method.