JPH1184171A - Optical connector - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make the intensity of light emitted from the end face of an optical fiber to a photodetector approximately constant. SOLUTION: This optical connector is constituted by inserting the optical fiber 2 into a fiber housing chamber 13 of a housing body 10. The optical fiber 2 in this housing body 10 has a bending part formed by a bending means and adjusts the incident angle of the incident light on this bending part. The bending means consists of an insertion hole 11 which is formed at one side wall 10a of the housing body 10, a fiber extrusion hole 15 which is disposed at the other side wall (10b) and extrudes the optical fiber 2 and a fiber pressing part 32 which is fitted into this insertion hole 11. The fiber bending member 30 is mounted to one side wall of the housing body 10, by which the fiber pressing part 30 is butted against the optical fiber 2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical connector into which an optical fiber is inserted.

[0002]

2. Description of the Related Art Optical communication is known as a means for transmitting a large amount of information such as voice, images, data pulses, and the like. Optical communications typically transmit large amounts of information by once converting an electrical signal to light, propagating the light through an optical fiber, and reconverting the light into an electrical signal.

[0003] The transmission side converts an electric signal into light by a light emitting element such as a semiconductor laser or a light emitting diode. As shown in FIG. 6, when the light 5 is incident on the end face 2e of the optical fiber 2 from a light emitting element (not shown), it is first incident on the boundary surface 6 between the core 2a and the clad 2b. Since the lights 5a, 5b, and 5c having various incident angles θ are incident on the boundary surface 6, the light 5c having the incident angle θ smaller than the critical angle θc is refracted at the boundary surface 6 and is not reflected, and is incident. Angle is critical angle θc
The larger lights 5a and 5b are totally reflected at the boundary surface 6 without being refracted. Then, only the lights 5a and 5b totally reflected on the boundary surface 6 propagate in the core 2a.

In order to lay the optical fibers 2 long, it is necessary to connect the optical fibers 2 to each other. As a means for this, a conventional optical connector 60 as shown in FIG. 7 (Japanese Patent Application Laid-Open No. 63-301008) ) Has been proposed.

In FIG. 7, an optical connector 60 has an optical cable 61 inserted into a cable support 62, and an optical fiber 63 constituting the optical cable 61 and a coil spring 6.
4, the distal end of the optical fiber 63 is inserted into the ferrule 65, and the coil spring 64 is interposed between the ferrule 65 and the cable support 62 to hold the holder 66.
And the holder 66 is inserted into the plug body 67.

However, as shown in FIG. 8, when a plurality of optical fibers 7 are laid on the same path, a bent optical fiber 7a or a small optical fiber 7b is bent.
There is. Therefore, there is a drawback that the intensity of light emitted from the end face of the optical fiber 7 to a light receiving element such as a photodiode (not shown) differs depending on the installation route of the optical fiber 7 due to bending loss due to bending of the optical fiber 7. Was.

It is to be noted that a loss A inherent to an optical fiber such as infrared absorption or ultraviolet absorption, absorption by impurities, Rayleigh scattering, and radiation or scattering loss due to imperfect structure of the optical fiber, and bending of the optical fiber. The sum of the bending losses B (A + B) is called light loss α, and the light loss α is given by the following equation. α = 10 · log (P _i / P _o ) [dB] Here, P _o : light intensity of the optical fiber immediately after the optical connector P _i : light intensity of the optical fiber at the end of the laid optical cable.

[0008]

SUMMARY OF THE INVENTION In view of the above, the present invention provides an optical connector which makes the intensity of light emitted from the end face of an optical fiber to a light receiving element substantially constant irrespective of the optical fiber laying route. The purpose is to provide.

[0009]

According to the present invention, there is provided an optical connector comprising an optical fiber inserted into a fiber accommodating chamber of a housing body, wherein the optical fiber in the housing body is bent. An optical connector having a bent portion formed by the means and adjusting an incident angle of light incident on the bent portion is basically used (claim 1). A fiber bending member having an insertion hole formed in one side wall of the housing main body, a fiber pushing hole provided in the other side wall for pushing out the optical fiber, and a fiber pressing portion fitted in the insertion hole; The fiber bending member is mounted on one side wall of the housing main body, so that the fiber pressing portion is brought into contact with the optical fiber.

According to the first aspect, since the optical fiber in the housing body is bent by the bending means, the optical fiber has a bent portion. Thus, the degree of bending of the bent portion adjusts the magnitude relationship between the incident angle of light passing through the bent portion and the critical angle. That is, when light having various incident angles enters the bent portion, light having an incident angle smaller than the critical angle is refracted at the bent portion and does not propagate through the optical fiber. Light having an incident angle larger than the critical angle is reflected at the bent portion and propagates in the optical fiber.

According to the second aspect, when the fiber bending member is mounted on one side wall of the housing body, the fiber pressing portion passes through the insertion hole and hits the optical fiber. Since the fiber pressing portion pushes the optical fiber into the fiber extrusion hole of the housing body, a bent portion is formed in the optical fiber.

[0012]

Embodiments of the present invention will be described below with reference to the drawings. 1 to 5 show an embodiment of an optical connector according to the present invention. In FIG. 1, the optical connector 1 bends an optical fiber 2 inserted in a housing body 10 by a bending means.

The bending means is, as shown in FIGS. 1 and 2,
It has an insertion hole 11 formed in the housing main body 10, a fiber push-out hole 12 provided to face the insertion hole 11, and a pressing rib 31 fitted to the insertion hole 11 (corresponding to the fiber pressing portion) ( (Corresponding to the fiber bending member). The optical fiber 2 has a core 2a at the center, a clad 2b is provided around the outer peripheral surface of the core 2a, and the clad 2b is covered with a jacket 2c.

The housing body 10 forms a fiber housing chamber 13 into which the optical fiber 2 is inserted.
A core housing chamber 14 for inserting the core 2a and the clad 2b of the optical fiber 2 on the rear wall 10b, and a pair of locking projections 15, 15 on both side walls 10c.
A fiber extrusion hole 12 is formed in the lower wall 10d, and the lower wall 10d
Arm 16 having a lock projection 16a on the rear end side
Is coupled. Lower wall 1 of both side walls 10c, 10c
On the 0d side, a protruding wall 17 is provided.

The insertion hole 11 is formed in a direction perpendicular to the insertion direction (P direction) of the optical fiber 2. And
The fiber extrusion hole 12 is located below the insertion hole 11. The fiber push-out hole 12 is formed so that the optical fiber 2 can be slightly bent downward from within a fiber housing chamber 13 having substantially the same size as the outer shape of the optical fiber 2.

The cover 30 is formed to have an inverted U-shaped cross section.
A pair of engaging holes 32, 3 are formed in opposite side walls 30a, 30a.
2, and a pressing rib 31 is protruded from the inner surface of the upper wall 30b. The pressing rib 31 is located in a direction orthogonal to the P direction,
And protrudes downward. The width and thickness of the pressing rib 31 are set to desired sizes.

The projecting length of the pressing rib 31 is set so as to penetrate the upper wall 10a of the housing body 10 and hit the optical fiber 2. Adjusting the mounting state (for example, loose mounting or complete mounting) of the cover 30 mounted on the upper wall 10a of the housing body 10, or pressing the pressing rib 3
By changing the length of the protrusion 1, the degree of bending of the bending portion 3 formed on the optical fiber 2 can be adjusted. The internal shape of the insertion hole 11 is substantially the same as the cross section of the pressing rib 31.

Next, the case where the optical fiber 2 is bent by the pressing rib 31 will be described. As shown in FIG.
The jacket 2c is peeled from one end of the cladding 2b to expose the cladding 2b. One end face of the optical fiber 2 is
One end of the optical fiber 2 is inserted from the opening of the fiber accommodation chamber 13 until the core 2a and the clad 2b are inserted into the core accommodation chamber 14 until the optical fiber 2 comes into contact with the inner part of the optical fiber.

After the insertion, the engaging hole 32 of the cover 30 is engaged with the locking projection 15 of the housing main body 10 (see FIG. 1), so that the cover 30 is connected to the upper wall of the housing main body 10 as shown in FIG. Attach to 10a surface. When the cover 30 is mounted on the surface of the upper wall 10a, the pressing rib 31 of the cover 30
Is inserted into the insertion hole 11 and the pressing rib 31 is
Hit. As the pressing rib 31 enters, the optical fiber 2 gradually moves downward and is pushed out from the fiber pushing hole 12. By pushing it completely,
A bent portion 3 is formed in the optical fiber 2.

As described above, a part of the optical fiber 2 is bent by abutting the pressing rib 31 against the optical fiber 2 inserted into the fiber accommodating chamber 13. This is for adjusting the intensity of the light 5 emitted from the end face 2d to the light receiving element 4. By the adjustment, as shown in FIG. 5, the light 5 'emitted from the end face 2d of the optical fiber 2 to the light receiving element 4 becomes only the light 5a and 5b having an incident angle larger than the critical angle θc. The intensity of light 5 ′ emitted from each end face 2 d of the optical fiber 2 can be made substantially constant. In addition, 5
c indicates light having an incident angle smaller than the critical angle θc, and indicates that the light is refracted without being reflected at the boundary surface 6.

Thus, the light receiving elements 4 having a constant sensitivity can be commonly used. Therefore, the laying cost of the optical fiber 2 can be reduced as compared with the related art. Then, the degree of freedom in designing the optical fiber laying path is increased, and the design efficiency is improved.

[0022]

As described above, according to the first and second aspects, when the fiber bending member is mounted on the housing main body, the fiber pressing portion inserted into the insertion hole pushes the optical fiber into the fiber extrusion hole. , A bent portion is formed in the optical fiber. Since light incident on the bent portion has various types of incident angles, light having an incident angle smaller than the critical angle is refracted without being reflected at the bent portion, and light having an incident angle larger than the critical angle is reflected at the bent portion. The light can be totally reflected and propagated in the optical fiber without being refracted.

Thus, for example, even if the optical fibers are laid on the same path but bent at different angles, the intensity of light incident on the light receiving element from the end face of the optical fiber is adjusted to be substantially constant. be able to. That is, variation in light intensity can be reduced. Therefore, since it is not necessary to replace the light receiving element in accordance with the light intensity, the cost required for laying the optical fiber is reduced as compared with the related art.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view showing an embodiment of an optical connector according to the present invention.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is an exploded view showing a state where an optical fiber is inserted into a housing body.

FIG. 4 is a cross-sectional view showing a state in which an optical fiber is bent with a housing body cover attached.

FIG. 5 is a diagram illustrating a state of light incident on a bent portion of the optical fiber.

FIG. 6 is a diagram illustrating a state in which light is incident on a boundary surface of an optical fiber.

FIG. 7 is an exploded perspective view showing a conventional optical connector.

FIG. 8 is a diagram showing a bent state of the laid optical fiber.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Optical connector 2 Optical fiber 3 Bending part 10 Housing main body 11 Insertion hole 12 Fiber extrusion hole 30 Fiber bending member 31 Fiber pressing part

Claims (2)

[Claims] 1. An optical connector comprising an optical fiber inserted into a fiber accommodating chamber of a housing main body, wherein the optical fiber in the housing main body has a bent portion formed by bending means, and is incident on the bent portion. An optical connector characterized by adjusting an incident angle of light to be emitted. 2. The optical fiber according to claim 2, wherein the bending means is provided on one side wall of the housing main body, a fiber push-out hole provided on the other side wall for pushing out the optical fiber, and a fiber pressing portion fitted into the insertion hole. 2. The optical connector according to claim 1, further comprising: a fiber bending member having: a fiber bending member attached to one side wall of the housing main body, so that the fiber pressing portion abuts on the optical fiber.