JP5342262B2 - Optical connector - Google Patents

Description

  The present invention relates to an optical connector including a ferrule with a built-in optical fiber and end-face polished and a connection mechanism integrated with the ferrule, and in particular, an optical fiber butt connection state between the built-in optical fiber and the inserted optical fiber when the connector is assembled. It is related with the optical connector which made it easy to confirm.

The optical connector of the present invention is similar in appearance to a conventional optical connector, but FIGS. 1 to 5 show an example of the optical connector.
The optical connector 1 includes a ferrule 3 including a built-in optical fiber (bare fiber) 2 and a connection mechanism 4 extending to the opposite side of the connection end surface 3 b of the ferrule 3.
The connection mechanism 4 includes a base 6 having a positioning groove 5 formed in the optical fiber hole 3 a of the ferrule 3, a lid portion facing the base 6, and a C-shaped or U-shaped leaf spring 9 that elastically clamps both. It is configured. The positioning groove 5 of the base 6 is directly continuous with the optical fiber hole 3a, and includes a positioning groove 5a that accommodates the optical fibers 2 and 10a to be butt-connected, and a positioning groove 5b that accommodates the covering portion 10b of the insertion optical fiber 10. It consists of.
The lid part is divided into two parts: a lid part 7 for opening and closing the connecting part for opening and closing the butted joint part P of the optical fiber, and a lid part 8 for opening and closing the insertion optical fiber coating part for opening and closing the coating part 10 b of the insertion optical fiber 10. It is divided. Hereinafter, both the base 6 and the lid portions 7 and 8 may be referred to as elements.
A wedge-type opening / closing member 11 that opens and closes the lids 7 and 8 with respect to the base 6 against the reaction force of the leaf spring 9 is prepared. A recess 12 for inserting the opening / closing member is formed between the base 6 and the lid portions 7 and 8, respectively. The opening / closing member 11 is used only when the optical connector is assembled.

Although the base 6 and the lids 7 and 8 of the connection mechanism in this type of conventional optical connector are resin molded products, ULTEM 2400, which is a 40% glass fiber reinforced polyetherimide resin, is widely used as a resin material. Yes.
This Ultem 2400 is used as a material for the base and lid of the connection mechanism because of its excellent mechanical properties, injection molding with thermoplastic resin, and low molding shrinkage. Is mainly due to the good UV resistance, but black ones are used.

  When the optical connector 1 is assembled, the opening / closing member 11 is inserted into the recess 12 for inserting the opening / closing member formed between the base 6 and the lid portion 7 or 8, and the lids 7 and 8 are opened from the outside. An insertion optical fiber (bare fiber) 10a is inserted, the built-in optical fiber 2 and the insertion optical fiber 10a are brought into contact with each other, and then the connection is confirmed. Then, the opening / closing member 11 is pulled out and the base 6 and the lid portion 7 are removed by the leaf spring 9. 8, the optical fiber butt connection portion P is sandwiched, and the covering portion 10 b of the inserted optical fiber 10 is sandwiched.

  In assembling the optical connector 1, as a method for confirming whether the built-in optical fiber 2 and the insertion optical fiber 10a are correctly butt-connected, the open / close member 11 is formed of a light-transmitting material, and the test light is transmitted through There is a method of visually observing light that enters the built-in optical fiber 2 from the connection end surface 3b of the connector 1 and leaks from the butted connection portion P through the opening / closing member 11 having optical transparency.

That is, as shown in FIG. 7, an optical connector 15 for connection confirmation is connected to the optical connector 1 to be confirmed for connection, and a light source (LD) is connected to a short optical fiber 16 for testing attached to the optical connector 15. (Laser diode) Light source 17 emits light, and the light leaking from the tip of the optical fiber 2 through the opening / closing member 11, that is, the leaking light directed in the radial direction as indicated by the arrow in FIG. 5 is visually observed. (Patent Document 1 (however, slightly modified)).
FIG. 7A shows a state before the insertion optical fiber 10 a is inserted into the optical connector 1. In this state, light emitted from the light source 17 and introduced into the built-in optical fiber 2 is transmitted from the tip of the built-in optical fiber 2. Although the light is emitted, since the opening / closing member 11 has optical transparency, it leaks to the outside of the optical connector 1 through the opening / closing member 11, and the opening / closing member 11 is observed brightly.
FIG. 7B shows a state in which the insertion optical fiber 10a is inserted into the optical connector 1 and the built-in optical fiber 2 and the insertion optical fiber 10a are butted together. If this butt connection is properly performed, light is emitted from the light source 17 and introduced into the built-in optical fiber 2, and the light passes through the butt connection portion P without leaking at the butt connection portion P. Therefore, light does not leak from the opening / closing member 11 to the outside of the optical connector 1, and the opening / closing member 11 is observed darkly. Therefore, it can be confirmed that the built-in optical fiber 2 and the insertion optical fiber 10a are properly butt-connected.
On the other hand, when the opening / closing member 11 is observed to be bright to some extent, it indicates that light is leaking from the butt connection portion of both optical fibers 2 and 10a, and it can be seen that the butt connection state is incomplete.
By observing light leaking from the opening / closing member 11 when the insertion optical fiber 10a is abutted against the built-in optical fiber 2 as described above (observing the brightness of the opening / closing member 11), the built-in optical fiber 2 and the insertion optical fiber 10a are It can be confirmed whether or not the butt connection is properly made.

JP-A-2005-292429

  With the above optical connector connection confirmation method, the butt connection state between the built-in optical fiber 2 and the insertion optical fiber 10a can be confirmed. However, in order to always perform correct connection confirmation, the butt connection state is good. The difference in the brightness of the leaked light from the case of the defect is remarkable, and it is necessary to easily identify the difference visually.

  However, in the conventional optical connector in which the elements (base 6 and lids 7 and 8) are black, the leak light itself is not so bright when the insertion optical fiber 10a is not inserted, and therefore the insertion optical fiber is built-in. Even if it is properly matched with the optical fiber and the amount of light leaked is small, the difference in brightness is small and it is not always easy to check the connection status, and it is not always easy to check the connection correctly. It was.

The inventors of the present application conducted an experiment to examine the brightness of leaked light leaking from the optical connector to the outside (brightness of the opening / closing member) under various conditions, and the color of the element of the connection mechanism greatly affected the amount of leaked light. I found out. That is, the leakage light is not so bright in the conventional black Ultem 2400, but the leakage light is remarkably bright in the same Ultem 2400 when the color is, for example, amber (yellowish brown), white or gray. I found out that
As shown in FIG. 5, the leaked light is light that travels in the radial direction through the gap between the upper and lower elements (base 6 and lid 7), so the colors of elements 6 and 7 seem to be irrelevant, but the brightness is actually remarkable. This difference may occur because the amount of light leaking to the outside is reduced by absorbing light on the surface when the element is black.

  The present invention is based on the above knowledge, and an object of the present invention is to provide an optical connector in which it is easier to check the butt connection state between the built-in optical fiber and the insertion optical fiber when the optical connector is assembled.

The optical connector of the invention of claim 1 for solving the above-mentioned problem comprises a ferrule having a built-in optical fiber and end-face polished, and a connection mechanism that is integrated with the ferrule and extends to the opposite side of the connection end face of the ferrule. ,
The connection mechanism includes a base in which a positioning groove continuous to the optical fiber hole of the ferrule is formed, a lid portion facing the base, and a leaf spring that elastically clamps both of the lid portion. A lid for opening and closing a connecting portion that opens and closes a butt connection portion of a fiber and a lid for opening and closing an insertion optical fiber covering portion that opens and closes a covering portion of an insertion optical fiber, and each lid portion is a wedge-shaped opening and closing member It can be opened and closed with respect to the base by
At least one of the base of the connection mechanism and the lid for opening / closing the connection part is made of a polyetherimide resin which is a glass fiber reinforced type and does not contain a pigment.

The optical connector of the invention of claim 2 includes a ferrule with a built-in optical fiber and end-face polishing, and a connection mechanism that is integrated with the ferrule and extends to the opposite side of the connection end face of the ferrule,
The connection mechanism includes a base in which a positioning groove continuous to the optical fiber hole of the ferrule is formed, a lid portion facing the base, and a leaf spring that elastically clamps both of the lid portion. A lid for opening and closing a connecting portion that opens and closes a butt connection portion of a fiber and a lid for opening and closing an insertion optical fiber covering portion that opens and closes a covering portion of an insertion optical fiber, and each lid portion is a wedge-shaped opening and closing member It can be opened and closed with respect to the base by
At least one of the base of the connection mechanism or the lid for opening / closing the connection part is made of a glass fiber reinforced type amber, white or gray polyetherimide resin.

  According to a third aspect of the present invention, in the optical connector of the first or second aspect, at least one of the base of the connection mechanism or the lid for opening / closing the connection portion is made of ULTEM 2400-1000 (natural).

In the optical connector of the present invention, in order to confirm the butt connection state of the built-in optical fiber and the insertion optical fiber at the time of assembly, test light is incident on the built-in optical fiber from the connection end surface of the ferrule, and the opening / closing member is formed from the vicinity of the butt connection portion. The leakage light leaking to the outside of the optical connector is observed, and when the leakage light is dark, it is judged that the connection state is good, and when it is bright, it is judged as bad.
Ultem 2400 (natural) is a polyetherimide resin to which no pigment is added, and is generally amber. As a result of conducting a connection confirmation experiment on an optical connector using an element (base or lid) made of this resin, as compared with an optical connector in which the element is black, the optical connector passes from the vicinity of the tip of the built-in optical fiber through an opening / closing member. The amount of light leaking to the outside increased significantly.
The amount of leakage light increases when the butt connection is good or bad, but the amount of leakage light is particularly large when the butt connection is bad. As a result, the difference in brightness of the opening and closing members can be easily confirmed visually, and the butt connection state can be easily confirmed.

When the element of the connection mechanism is white or gray, the amount of light leaking from the vicinity of the end of the built-in optical fiber to the outside of the optical connector through the opening / closing member is increased as compared with the case of black. .

It is the perspective view which showed the optical connector of one Example of this invention with the opening-and-closing member. It is a side view of the optical connector of FIG. It is a longitudinal cross-sectional view of the optical connector of FIG. It is the top view of the principal part which decomposed | disassembled and showed the optical connector of FIG. It is an expanded cross-sectional view of the state which opened the connection mechanism of the said optical connector with the opening-and-closing member. It is a longitudinal cross-sectional view of the use state of the said optical connector. It is a figure explaining the condition at the time of confirming the optical fiber butt | matching connection state in the said optical connector, (a) is a state before inserting an insertion optical fiber, (b) is a built-in optical fiber by inserting an insertion optical fiber. Shows the state of matching.

  Hereinafter, an optical connector embodying the present invention will be described with reference to the drawings.

FIG. 1 is a perspective view showing the appearance of an optical connector 1 according to an embodiment of the present invention together with an opening / closing member, FIG. 2 is a side view of the optical connector 1 of FIG. 1, and FIG.
The optical connector 1 includes a ferrule 3 having a built-in optical fiber (bare fiber with a coating removed) 2 and subjected to end surface polishing, and a connection mechanism 4 extending to the opposite side of the connection end surface 3 b of the ferrule 3. Yes.
The connecting mechanism 4 elastically clamps a base 6 in which a positioning groove 5 continuous to the optical fiber hole 3a of the ferrule 3 is formed, a lid portion facing the base 6, and a C-shaped leaf spring in the illustrated example. 9.
The base 6 is formed integrally with a cylindrical ferrule fitting portion 13 and a flange-like flange portion 14 for fitting the ferrule 3 together, and extends from the flange portion 14 to the opposite side to the connection end surface 3b of the ferrule 3. ing.
As shown in FIG. 4, the positioning groove 5 of the base 6 includes a positioning groove 5 a for receiving the optical fibers 2 and 10 a to be butt-connected to the optical fiber hole 3 a and a covering of the insertion optical fiber 10. The positioning groove 5b accommodates the portion 10b.
The lid part is divided into two parts: a lid part 7 for opening and closing the connecting part for opening and closing the butted joint part P of the optical fiber, and a lid part 8 for opening and closing the insertion optical fiber coating part for opening and closing the coating part 10 b of the insertion optical fiber 10. It is divided.
In some cases, both the base 6 and the lid portions 7 and 8 are referred to as elements. In this embodiment, each element (the base 6 and the lid portions 7 and 8) is a polyetherimide resin of 40% glass fiber reinforced type, and “Ultem 2400 (Natural)” (registered trademark of General Electric Co., Ltd.) to which no pigment is added. This natural Ultem 2400 with no added pigment is generally amber.

A wedge-type opening / closing member 11 that opens and closes the lids 7 and 8 with respect to the base 6 against the reaction force of the leaf spring 9 is prepared.
As shown in FIG. 1, the opening / closing member 11 includes a wedge portion 11 a for opening the lid portion 7 for opening and closing the connection portion and a wedge portion 11 b for opening the lid portion 8 for opening and closing the insertion optical fiber coating portion. The wedge part is provided integrally.
Between the base 6 and the lid part 7 or 8, two recesses 12 for inserting the opening / closing member into which the two wedge parts 11a, 11b of the opening / closing member 11 are respectively inserted are formed.
The opening / closing member 11 is used only at the time of assembling the optical connector, but is formed of a light transmissive resin so as to be compatible with the connection confirmation test.
The inner surface of the lid portion 7 for opening / closing the connecting portion is a flat surface, and the inner surface of the lid portion 8 for opening / closing the insertion optical fiber coating portion is provided with a bare fiber 10a portion of the insertion optical fiber 10 as shown in FIG. A positioning groove 5a ′ for accommodating and a positioning groove 5b ′ for accommodating the covering portion 10b are formed.

The optical connector 1 has a configuration in which end surface polishing is performed in advance at the factory and the covering portion 10b of the insertion optical fiber 10 can be clamped, and is generally called a field assembly type optical connector because it is easy to assemble in the field. ing.
When the optical connector 1 is assembled, two wedge portions 11a and 11b of the opening / closing member 11 are formed between the base 6 and the lid portion 7 or 8 as shown in FIG. Then, the lids 7 and 8 are slightly opened.
In this state, an insertion optical fiber (a bare fiber at the tip) 10a is inserted from the outside, and the built-in optical fiber 2 and the insertion optical fiber 10a are butted together.
A refractive index matching agent is filled between the end faces of both optical fibers.
Next, the opening / closing member 11 is pulled out, and the butted connection portion P of the optical fiber is sandwiched between the base 6 and the lid portions 7 and 8 by the leaf spring 9, and the covering portion 10 b of the inserted optical fiber 10 is sandwiched.

FIG. 6 shows an optical connector device 50 as an example when the optical connector 1 is specifically used.
The optical connector device 50 covers the connection mechanism 4 in the optical connector 1 with a spring 51 for urging the connection mechanism 4 forward against the rear end surface thereof, and covers the ferrule 3 and the connection mechanism. This is a configuration in which a housing 53 is put on the front portion of the No. 4.
The configuration of the optical connector device 50 is employed when the optical connector device 50 is inserted into an optical connector adapter or the like and connected to another optical connector, for example.

When the optical connector 1 is assembled, a connection confirmation test for confirming whether or not the butt connection between the built-in optical fiber 2 and the insertion optical fiber 10a is correctly performed is performed as follows.
FIG. 7A shows a state before the insertion optical fiber 10 a is inserted into the optical connector 1. In this state, the light emitted from the light source 17 and introduced into the built-in optical fiber 2 is the tip end of the built-in optical fiber 2. However, since the opening / closing member 11 has light permeability, it leaks to the outside of the optical connector 1 through the opening / closing member 11. That is, from the vicinity of the tip of the built-in optical fiber 2, it passes through the opening / closing member 11 in the radial direction as indicated by an arrow in FIG. 5 and leaks to the outside. That is, the opening / closing member 11 is observed brightly.
FIG. 7B shows a state in which the insertion optical fiber 10a is inserted into the optical connector 1 and the built-in optical fiber 2 and the insertion optical fiber 10a are butted together. If this butt connection is properly performed, the light emitted from the light source 17 and introduced into the built-in optical fiber 2 passes through the butt connection portion P without leaking at the butt connection portion P. Light does not leak. Therefore, light does not leak from the opening / closing member 11 to the outside of the optical connector 1, and the opening / closing member 11 is observed darkly. Therefore, it can be confirmed that the built-in optical fiber 2 and the insertion optical fiber 10a are properly butt-connected.
On the other hand, when the opening / closing member 11 is observed to be bright to some extent, it indicates that light is leaking from the butt connection portion of both optical fibers 2 and 10a, and it can be seen that the butt connection state is incomplete.
Thus, by visually observing light leaking from the opening / closing member 11 when the inserted optical fiber 10a is butted against the built-in optical fiber 2, it is determined whether or not the built-in optical fiber 2 and the inserted optical fiber 10a are properly butted and connected. I can confirm.

The principle of confirming the connection state is as described above. As described above, in the connection confirmation experiment performed on the optical connector in which the elements 6, 7, and 8 are made of the conventional black Ultem 2400, the insertion optical fiber 10a is inserted. The leak light itself was not so bright.
However, in the connection confirmation experiment performed on the optical connector of the example in which the elements 6, 7, and 8 are the dark blue Ultem 2400 (natural), it was remarkably brighter than the case of the conventional black element. The brightness of the leaked light was visually observed as in the normal connection confirmation test, but the difference was remarkable.
As shown in FIG. 5, the leaked light is light that travels in the radial direction through the gap between the upper and lower elements (base 6 and lid 7), so the colors of elements 6 and 7 seem to be irrelevant, but the brightness is actually remarkable. This difference is considered to occur because the amount of light leaking to the outside is reduced because light is absorbed when the element is black.
When the inserted optical fiber is properly abutted against the built-in optical fiber 2, the amount of leaked light is small and the leaked light becomes dark, but the leaked light is sufficiently bright when the inserted optical fiber is not inserted. The difference is large, and it can be easily and reliably confirmed whether or not the butt connection is good.

In the above-described embodiment, each of the elements 6, 7, and 8 is formed of amber Ultem 2400 (natural), but an optical connector in which each of the elements 6, 7, and 8 is formed of a white Ultem 2400 is manufactured. As a result of a similar connection confirmation experiment, the leakage light to the outside of the optical connector was larger than that of the conventional product using the black Ultem 2400, and the opening / closing member was observed to be remarkably bright.
Further, when an optical connector in which each element 6, 7, 8 was formed of gray Ultem 2400 was produced and a connection confirmation experiment was performed in the same manner, the optical connector was compared with the conventional product using black Ultem 2400. The leakage light to the outside of the light was large, and the opening / closing member was observed to be remarkably bright.
In addition, when the optical connector which formed each element 6,7,8 with the transparent Ultem 2400 was produced and the connection confirmation experiment was done similarly, compared with the case of amber, white, or gray, the opening / closing member is Observed quite dark. This is presumably because, if the element is transparent, light passes through the element itself and is dissipated, so that light leaking from the opening / closing member is reduced.
In the present invention, amber, white, and gray naturally have a slight width.
If the element is formed of Ultem 2400 having a color that absorbs little light other than amber, white, or gray, the amount of leakage light can be increased as compared with the case of a black element.

In the connection confirmation experiment, the connection between the optical connector 15 for connection confirmation and the optical connector 1 was performed in the optical adapter.
Also, standard optical fibers (bare fibers) 2 and 10a were made of standard 125 μm diameter quartz single mode transmission type optical fibers.
As the light source, an LD light source that emits light having a wavelength of 650 μm, which is usually used for optical communication, was used.
In the above-described embodiment, it has been described that the connection state is determined by visually observing the leaked light. However, it is naturally possible to measure the leaked light quantity with a meter.

1 Optical connector 2 Built-in optical fiber (bare fiber with coating removed)
3 Ferrule 3a Optical fiber hole 3b Connection end face 4 (of ferrule) Connection mechanism 5 Positioning groove 5a, 5b Positioning groove 5a ', 5b' (on the base side) Positioning groove 6 Base 7 (For opening / closing the connection part) ) Lid portion 8 (for opening / closing the optical fiber coating portion) 9 Leaf spring 10 Inserting optical fiber (the whole including the bare fiber portion and the coating portion)
10a Optical fiber (bare fiber of insertion optical fiber)
10b Coated part (coated optical fiber coated part)
11 Opening / closing member 11a Wedge portion 11b (on the lid portion side for opening / closing the connection portion) Wedge portion 12 (on the lid portion side for opening / closing the optical fiber covering portion) 12 Recess 13 (for inserting the opening / closing member) Ferrule fitting portion 14 Flange part 15 Optical connector 16 for connection confirmation Optical fiber 17 for connection confirmation Light source P for connection confirmation Butt connection part

Claims (3)

A ferrule with a built-in optical fiber and polished end face, and a connection mechanism that is integrated with the ferrule and extends to the opposite side of the ferrule connection end face,
The connection mechanism includes a base in which a positioning groove continuous to the optical fiber hole of the ferrule is formed, a lid portion facing the base, and a leaf spring that elastically clamps both of the lid portion. A lid for opening and closing a connecting portion that opens and closes a butt connection portion of a fiber and a lid for opening and closing an insertion optical fiber covering portion that opens and closes a covering portion of an insertion optical fiber, and each lid portion is a wedge-shaped opening and closing member It can be opened and closed with respect to the base by
An optical connector, wherein at least one of a base of the connection mechanism or a lid for opening / closing the connection portion is made of a polyetherimide resin which is a glass fiber reinforced type and has no pigment added thereto. A ferrule with a built-in optical fiber and polished end face, and a connection mechanism that is integrated with the ferrule and extends to the opposite side of the ferrule connection end face,
The connection mechanism includes a base in which a positioning groove continuous to the optical fiber hole of the ferrule is formed, a lid portion facing the base, and a leaf spring that elastically clamps both of the lid portion. A lid for opening and closing a connecting portion that opens and closes a butt connection portion of a fiber and a lid for opening and closing an insertion optical fiber covering portion that opens and closes a covering portion of an insertion optical fiber, and each lid portion is a wedge-shaped opening and closing member It can be opened and closed with respect to the base by
An optical connector, wherein at least one of a base of the connection mechanism or a lid for opening and closing the connection part is made of a glass fiber reinforced type amber, white or gray polyetherimide resin. The optical connector according to claim 1, wherein at least one of the base of the connection mechanism and the lid for opening / closing the connection portion is made of Ultem 2400 (natural).

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