JPS61132910A - Optical connector - Google Patents

Abstract

PURPOSE:To eliminate the spacing in the juncture of optical fibers and to decrease the reflection loss at the juncture by projecting slightly the front ends of the optical fibers held and fixed in ferrules and connecting the fibers. CONSTITUTION:The optical fibers 1 of an optical connector are projected by several mum from the front ends of the ferrules 2. Such ferrules 2 are connected by using an aligning sleeve 3, then the direct contact of the optical fibers 1 with each other is resulted and the spacing in the juncture is easily made to the wavelength of the used light o below while the fibers are heretofore spaced at about several - several tens mum. The decrease of the reflection loss at the juncture is thus made possible. The extension of the transmission distance of the optical fiber and the stable laser outgoing, etc. are thereby made possible.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to the structure of a non-reflective optical connector for coupling optical transmission lines.

[Conventional technology]

Optical connectors are being actively developed to facilitate the connection of optical fibers. Conventionally, when connecting optical fibers to each other using optical connectors.

The purpose is to obtain stable connection loss, and this causes fluctuations in the intensity of the reflected light. In order to prevent interference between the optical fibers, the optical fibers are spaced apart by several micrometers to several tens of micrometers.

[Problem that the invention seeks to solve]

However, in this case, a loss occurs at the connection due to Fresnel reflection. There is a problem. If the refractive index of the optical fiber core is 1.46, this reflection loss is approximately 0.3 dB at the connection portion. As a means for reducing reflection loss, (1) A matching oil having a refractive index approximately equal to that of the optical fiber is used.

■ Insert a transparent resin with a refractive index almost equal to that of the optical fiber.

However, all of these methods lack long-term stability and also have poor operability.

Further, this reflection causes the problem that the oscillation of the laser light source becomes unstable.

An object of the present invention is to provide a non-reflective optical connector that eliminates the above-mentioned problems.

[Means for solving problems]

The optical connector of the present invention is an optical connector for optically connecting the tip of a first optical fiber held and fixed to a ferrule and the tip of another second optical fiber. It is characterized by the tip of the first optical fiber protruding.

〔Example〕

Next, two embodiments of the present invention will be described with reference to the drawings.

In FIG. 1 showing the optical connector according to the first embodiment of the present invention, the optical fiber 1 also protrudes several μm from the tip of the ferrule 2. When this optical connector is connected using the alignment sleeve 3, the tips of the optical fibers 1 protrude beyond the tips of the ferrule 2, so the optical fibers 1 come into contact with each other. The following.

Reflection loss at the connection part is eliminated.

FIG. 2 shows an optical connector according to a second embodiment of the present invention. As shown in FIG. 2(a), the optical fiber 1 is fixed to the ferrule 2 using an elastic silicone resin 4 or the like with its tip slightly protruding. When two optical connectors are brought into contact with each other in the alignment sleeve 3 as shown in FIG. Stand still. Also in this optical connector, the spacing between the optical fibers 1 is easily equal to or less than the optical wavelength, and reflection loss at the connection portion is eliminated. In addition, the fiber contact pressure is
By concave in the axial direction, proper contact surface pressure is maintained, so the fiber will not be damaged. ・If there is slight variation in the polishing angle of the ferrule end face of an optical connector, there will generally be a gap between the optical fibers. Although it is easy to occur, the light of the present invention is 2;
In a connector, if an elastic body with lower hardness than the optical fiber is used for the ferrule, the end face of the ferrule will also be recessed when the optical fiber is connected, so there is an advantage that no gap will be created at the connection point of the optical fiber. In addition, if the ferrule is made of an object with lower hardness than the optical fiber, the tip of the ferrule that holds and fixes the optical fiber can be machined into a convex spherical shape, making it easy to align the center of the two spherical surfaces with the center of the optical fiber core. .

In this case, the tip of the protruding optical fiber has a spherical surface.

〔Effect of the invention〕

As described above, by using the optical connector of the present invention, it is possible to reduce the reflection loss that conventionally occurs at the connection portion, and it is possible to extend the transmission distance of the optical fiber. Further, the effect on the laser light source can be alleviated, and stable laser oscillation can be ensured. In addition, in normal right-angle polished connectors, if the polished surface and the optical axis are not perpendicular to each other, a gap occurs at the connection part, but in the optical connector of the present invention, the optical fiber protrudes beyond the ferrule tip. No gaps are created.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view showing a connection part of an optical connector according to a first embodiment of the present invention, FIG. 2 is a cross-sectional view showing an optical connector according to a second embodiment of the present invention, and FIG. This is a cross-sectional view showing the shape of the tip of the optical connector when it is not connected.
) is a cross-sectional diagram showing the connection state, 4... silicon m
Fat.

Claims (1)

[Claims] 1. In an optical connector that optically connects the tip of a first optical fiber held and fixed to a ferrule and the tip of another second optical fiber, the tip of the first optical fiber is lower than the tip of the ferrule. An optical connector characterized in that a first optical fiber has a protruding tip. 2. The optical connector according to claim 1, wherein the ferrule has a lower hardness than the first optical fiber. 3. The optical connector according to claim 1 or 2, wherein the first optical fiber held by the ferrule is slightly movable in the axial direction within the ferrule. 4. Claim 1, 2 or 3, characterized in that the tip of the protruding first optical fiber is spherical.
Optical connector described in section.