JPS6170521A - Optical fixed attenuator - Google Patents

Abstract

PURPOSE:To perform stable and high-precision fitting connection by providing a ferrule, where an optical fiber is inserted and fixed to the axis and which is provided with an optical attenuating pat and providing a gap between the ferrule inserted to an aligning sleeve and a casing member. CONSTITUTION:An optical fiber 1 is fixed onto the axis of a ferrule 2, and a cylindrical spacer 13 and an aligning sleeve 5 having elasticity in the axial direction are attached to one end of the ferrule 2. A whirl stop 7 is attached to the ferrule 2, and the whirl stop 7 is fitted to a notch 6a provided in a housing 6 to prevent rotation of the ferrule 2. Thus, one end of a fixed attenuator can be fitted to an adpater 10 and is fixed by a knob 8. Menwhile, the other end is so structured that a connector 9 is fitted to it, and a plug 11 of the connector 9 is connected to the ferrul 2 through the spacer 13 by the sleeve 5. The spacer 13 has an optical attenuating function, and the thickness is adjusted to set an optional quantity of attenuation. Thus, stable connection is secured.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a fixed optical attenuator used for adjusting the light emission level of a light source used in optical fiber communication, adjusting the light receiving level of a light receiver, etc. .

[Conventional technology]

In optical communication systems, fixed optical attenuators are indispensable as pseudo-lines when the received light intensity exceeds an appropriate level. As a conventional optical fixed attenuator, the 1978
In 2009, the Institute of Electronics and Communication Engineers, Semiconductor and Materials Division National Conference Proceedings and 336 Low Reflection Fixed Attenuators, etc. FIG. 3 is a diagram showing the configuration of this low reflection light fixed attenuator. This fixed optical attenuator is made up of two ferrules 2 into which an optical fiber 1 is inserted and fixed, butted against each other within a cylindrical sleeve 3. This optical fixed attenuator has an optical connector grab on the input side, and a receptacle of the light receiving module on the output side.
It has a structure in which an optical connector plug is fitted via an optical adapter. A vapor deposited film 4 made of a NiCr alloy is formed on one of the abutting surfaces, and this vapor deposited film 4 reflects a portion of the incident light and attenuates it. In order to prevent the reflected light from the vapor-deposited film 4 from returning to the light source, the abutting surface is oriented at 2 degrees with respect to the axis perpendicular to the optical axis of the optical fiber.
Beveled to 0 degrees. Furthermore, the optical fiber 1 on both the input side and the output side of the 7-erule 2 is polished at an 8 degree angle to create a structure that is compatible with an obliquely polished connector (Suzuki et al., 1981 Institute of Electronics and Communication Engineers National Conference Proceedings A2232). ing. In the single optical fixed attenuator, the optical fiber 1 is a step-index fiber with a core diameter of 80 μm.

[Problem that the invention seeks to solve]

However, as shown in FIG. 3, in the case where the ferrules are butted together in the cylindrical sleeve 3 and the cylindrical sleeve 3 is structured to fit into an optical connector plug or an optical receptacle of the transmission line, the cylindrical sleeve 3 and the ferrule 2 If the coaxiality of the optical connector is poor, an external force is applied in a direction perpendicular to the optical axis when mating with another optical connector plug, causing axis misalignment, resulting in poor reproducibility of attachment and detachment. Further, there is a drawback that if the ferrule 2 is attached and detached multiple times, the tip of the ferrule 2 and other optical connector plugs may be deformed or damaged. Therefore,
In the conventional structure, a high degree of alignment accuracy was required to adjust the coaxiality of the ferrule 2 and the cylindrical sleeve 3.

An object of the present invention is to eliminate such drawbacks and provide an optical fixed attenuator in which a ferrule having an optical attenuation function can be easily and accurately fitted into other optical connector grabs or optical receptacles. .

[Failure to solve the problem]

The fixed optical attenuator of the present invention has an optical fixed attenuator having a fastening mechanism for an optical adapter and an optical receptacle coaxially, and a fitting mechanism for an optical connector plug, in which an optical fiber is inserted and fixed on the central axis, and.

It is characterized in that it contains at least one 7-ferrule having a light attenuating portion inside, and the inside of the ferrule is movable.

That is, according to two aspects of the present invention, in an optical fixed attenuator having a coaxial coupling mechanism with an optical adapter or optical receptacle and a fitting mechanism with an optical connector grab, an optical fiber is inserted and fixed on the central axis, and The ferrule includes at least one ferrule having a light attenuating portion, an alignment sleeve into which one end of the ferrule is inserted almost to the center, and an exterior member that holds the ferrule and the alignment sleeve, and the ferrule is inserted into the alignment sleeve. Optical fixed attenuator O characterized in that there is a gap between the ferrule and the exterior member. [Embodiments] Next, two embodiments of the present invention will be described with reference to the drawings. Referring to FIG. 1, in an optical fixed attenuator according to an embodiment of the present invention, an optical fiber 1 is fixed on the central axis of a ferrule 2, and both ends of the ferrule 2 are optically polished. A cylindrical spacer 13 and an alignment sleeve 5 are attached to one end of the ferrule 2. The alignment sleeve 5 is made of phosphor bronze and has elasticity in the central axis direction. Further, a rotation stopper (protrusion) 7 is attached to the ferrule 2, and by fitting this rotation stopper 7 into a notch 6a provided in the no-unong 6, This prevents the ferrule 2 from rotating.

If the ferrule 2 rotates inside the Hauplug, the amount of misalignment of the optical axis at the connection point between the ferrule 2 and the optical connector 9 due to eccentricity between the ferrule 2 and the optical fiber 1 will change, and the connection loss will change. This is because an inconvenience arises in that the amount of attenuation including connection loss also changes.

Further, the spring 12 has a function of connecting and holding the end faces of the ferrule 2 and the optical connector 9 with appropriate surface pressure.

One end of the optical fixed attenuator can be fitted into the adapter 10 and fixed by the knob 8. on the other hand.

The other end has a structure in which the optical connector 9 is fitted, and the plug 11 of the optical connector 9 is connected to the ferrule 2 via the cylindrical cover 13 by the alignment sleeve 5.

The spacer 13 has a light attenuation function. For example, when the optical fiber 1 of the transmission line is a single mode fiber, the distance between the optical fibers and the amount of attenuation have a relationship as shown in FIG. Therefore, by adjusting the thickness of the spacer 13, an arbitrary amount of attenuation can be obtained.

In this embodiment, as a method of attenuating light, the spacer 13 is
However, it is also possible to use a metal film such as Ti or NiCr instead of the spacer 13 so as not to create a gap between the fibers.

〔Effect of the invention〕

As described above, in the optical fixed attenuator of the present invention.

A ferrule 2 having an optical attenuation function is separated from a main body that is connected to other optical connectors, optical receptacles, etc. First, when inserting the plug side of the two optical fixed attenuators into an optical receptacle or optical adapter, use the 7 errule 2 inside the optical fixed attenuator.
moves independently of the fastening part of the optical fixed attenuator and is guided to the hole position of the optical receptacle or optical adapter. On the other hand, there are two optical fixed attenuators.

When the optical connector plug is inserted into the present attenuator while being fixed to an optical receptacle or the like, the optical connector plug moves slightly and is guided to the alignment strip 5 in the two-wire attenuator.

Therefore, in a single attenuator, the ferrule inside the attenuator is less likely to receive external force in the direction perpendicular to the optical axis, and stable connection is guaranteed.

Moreover, the tip of the plug will not be damaged.

[Mode of implementation]

Embodiments of the present invention are listed below.

1. An optical fixed attenuator having a coaxial coupling mechanism for an optical adapter or optical receptacle and a fitting mechanism for an optical connector grab, in which an optical fiber is inserted and fixed on the central axis, and at least an optical attenuator is provided. One ferrule and an alignment sleeve into which one end of the ferrule is inserted almost to the center.

An optical fixed attenuator, comprising: an exterior member that holds the ferrule and the alignment sleeve; and a gap is provided between the ferrule inserted into the alignment sleeve and the exterior member.

2. The fixed optical attenuator according to item 1 above, wherein the alignment sleeve has elasticity in the central axis direction.

3. The fixed optical attenuator according to item 1 or 2 above, wherein both ends of the ferrule having the optical attenuation portion have the same shape as the end face of the optical connector plug.

4. The optical fixed attenuator as described in item 1, item 2, or item 3 above, wherein the ferrule having the optical attenuator is held by an exterior component via a spring.

5. The optical fixed attenuator according to the above item 1, 2, 3, or 4, characterized by having a mechanism for preventing rotation of the ferrule having the optical attenuator.

6. The fixed optical attenuator according to item 5 above, wherein the rotation prevention mechanism comprises a housing having at least one convex portion provided on the ferrule and a notch into which the convex portion fits.

[Brief explanation of the drawing]

Figure 1 is a sectional view showing a fixed optical attenuator according to an embodiment of the present invention, Figure 2 is a diagram showing the relationship between the spacing of optical fibers and the amount of optical attenuation, and Figure 3 is a diagram showing a conventional fixed optical attenuator. FIG. In fig. DESCRIPTION OF SYMBOLS 1... Optical fiber 22... Ferrule, 3... Cylindrical sleeve, 4... Vapor deposited film, 5... Alignment sleeve,
6...Housing r 6 a...Cut, 7...
・Rotation stopper, 8...knob, 9...optical connector,
10...Adapter. 11...% lag, 12... spring, 13... spacer.

Claims (1)

[Claims] 1. An optical fixed attenuator having a coaxial coupling mechanism for an optical adapter or optical receptacle and a fitting mechanism for an optical connector plug, in which an optical fiber is inserted and fixed on the central axis, and at least an optical attenuator is provided. One ferrule, an alignment sleeve into which one end of the ferrule is inserted almost to the center, and an exterior member that holds the ferrule and the alignment sleeve, the ferrule and the exterior member inserted into the alignment sleeve. An optical fixed attenuator characterized by having a gap between.