JPH056162B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to optical connectors, and more particularly to optical connectors for precisely aligning optical fibers with the ends of other optical fibers or with sources of light radiation, such as lasers.

As used herein, the word "light" includes light invisible to the human eye, such as infrared and ultraviolet rays.

The present invention is particularly suited to aligning single mode optical fibers with solid state lasers because this type of alignment must be accurate to within 1 or 2 microns to avoid significant loss of light. It is. Direct alignment methods are difficult because the fibers must be fixed within these tolerances when aligned, for example by soldering or bonding with a suitable adhesive. Such fixing methods are usually ineffective because there is slight movement between the fiber and the laser as the solder or adhesive hardens.

The invention is also suitable for combining two single mode optical fibers due to the high degree of eccentricity of the fibers. Precision ferrule and V
Conventional mechanical alignment techniques, such as grooves, are usually only suitable for highly concentric fibers, and alignment of single mode fibers, such as by making them concentric by centerless grinding, is cumbersome and expensive.
Conventional techniques also do not provide good results, especially for connectors assembled in certain areas where attributes are useful.

It is an object of the present invention to provide an optical connector that overcomes or significantly reduces this problem.

In accordance with the present invention, an optical connector for precisely aligning an optical fiber and a light radiation source is provided that supports a distal end of the optical fiber and the light radiation source in spaced relation and generally aligned. at least two light deflection members arranged between the optical fiber and the light radiation source, at least one of the light deflection members being arranged so that the image of the light radiation source is It is rotatable approximately on the axis of the optical fiber end for movement to a position for focusing the optical fiber end.

Preferably there are two light deflection members, both of which are preferably substantially rotatable on the axis of the end of the optical fiber.

Each light deflection member has an axis disposed substantially on the axis of the optical fiber terminal and is rotatable about the axis, and at least one end face of the member is configured such that the on-axis rotation of the member Preferably, the deflection member is formed at an acute angle to the axis of said member so as to produce a movement of the image of said member. Preferably, two such cylindrical transparent members are provided substantially aligned in spaced relationship.

Adjacent ends of the two members preferably have surfaces formed at acute angles to the axis of their respective members.

The light source comprises an opto-electronic device such as a laser.

The light deflection member may be permanently fixed in place after the image of the light radiation source has been focused onto the end of the optical fiber, or alternatively may be temporarily fixed for future alignment operations.

Embodiments of the invention will be described by way of example only with reference to the drawings.

FIG. 1 shows the principle used to align an optical fiber 10 with a fixed injection laser diode 12. FIG. The axis of the fiber is generally aligned with the laser and two prisms 14 and 16 are inserted between the fiber and the laser. Prism end 1
8 and 20 are arranged at an angle, and fiber 10, prisms 14, 16 and laser 1
It can be seen that the relative movement between 2 focuses the laser image onto the end of fiber 10. Different angles of the prism ends 18 and 20 also change the position of the image.

The alignment method can be described as an "optical lever". That is, movement of one component of the optical system causes a very small movement of the light source image. Therefore, if the prism is fixed by soldering or gluing, a small amount of movement by the prism as the solder or adhesive hardens will effectively result in only a negligible amount of movement of the image. .

In FIG. 2, prisms 22, 24 are cylindrical with adjacent ends formed at acute angles to a plane perpendicular to their respective axes. The optical alignment of the image of the laser 12 on the end of the optical fiber 10 is 2
easily obtained by rotating one or both of the two prisms. The overall optical alignment is achieved by placing prisms 22, 24 in a V-groove 26 with optical axes reasonably aligned with the axes of fiber 10 and laser 12.
is conveniently maintained coaxially by placing the Mutual axial rotation of both prisms produces a circular image of the laser about the optical axis, and rotation of only one prism produces movement of the image through an arc toward or away from the optical axis. As a result, two prisms 2
The rotational movement of 2 and 24 makes it possible to image the laser on the end of the fiber even if these components are significantly off-axis.

The simplicity and coaxial nature of the array can be used in complex planar optical systems such as those required in wavelength-splitting composite subsystems.

The prism is usually a glass rod or a green (graded index of refraction) or self-focusing lens.

The prism can, for example, be permanently fixed after being imaged in a tightly sealed container, and alternatively a suitable device can be provided to temporarily fix the prism, but future realignment is possible outside the container. It is.

This method is suitable for precision alignment of various optical systems such as optical desks and fiber optic connectors (by passing light along one of two nearly aligned fibers) and integrated optical interconnects. It is.

FIG. 3 shows two similar housings 28 and 3.
0, the ends of the housing are used to receive the terminal ends of optical fibers 32 and 34. The housings are connected together in abutting relationship by a collar 36.

Each housing has a self-focusing lens 40,4
2 and two cylindrical wedges 44, 46, 48 and 50. The desired light beam is fiber 3
2 and by passing light along an axially adjusting self-focusing lens. wedge 4
Rotation of one or both of 4, 46 moves the direction of the beam until it is focused at the required location. Both housings can be focused independently, with the beam emerging from the housing centrally before the housings are tightened together, or the beam can be focused from the housing by rotating the wedge until the brightest light is obtained from the other fiber. can be adjusted after both are tightened. The self-focusing lens and wedge are thus accessible from the outside of the housing by appropriate grooves 52 and 54 formed in housings 28 and 30, respectively. The self-focusing lens and wedge can be fixed in place after focusing by thermosetting resin or left in place for future adjustment.

As used herein, the term "light deflecting member" refers to any transparent member designed to produce an output beam that has an angular displacement from an input beam, such as a regular prism, a diffraction grating, a diffusing lens or a weakly decentered lens. Also includes.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram showing an optical connector for aligning an optical fiber and a light source of the present invention, FIG. 2 is a perspective view showing an embodiment of the present invention, and FIG. 3 is a diagram showing an optical connector for aligning two optical fibers of the present invention. FIG. 3 is a cross-sectional view of an optical connector for coupling. 10, 32, 34: Optical fiber, 12: Laser diode, 14, 16, 22, 24: Prism, 40, 42: Self-focus lens, 4
4, 46, 48, 50: Cylindrical wedge.

Claims (1)

Claims: 1. An optical connector for accurately aligning an optical fiber and a light radiation source, wherein the end of the optical fiber and the light radiation source are spaced apart and substantially aligned. a support device for supporting and at least two light deflection members arranged between the optical fiber and the light radiation source, at least one of the light deflection members being arranged such that the image of the light radiation source is An optical connector characterized in that it is rotatable approximately on the axis of the optical fiber end so as to be able to move to a position where the optical fiber end can be brought into focus. 2. The optical connector according to claim 1, characterized in that it has two optical deflection members. 3. The optical connector according to claim 2, wherein both of the two optical deflection members are substantially rotatable on the axis of the end of the optical fiber. 4. In the optical connector according to any one of claims 1 to 3, each optical deflection member has an axis disposed substantially on the axis of the end of the optical fiber, and An optical connector characterized by having a cylindrical transparent member that is rotatable. 5. The optical connector of claim 4, wherein at least one end surface of each cylindrical transparent member is at an acute angle to the axis of the member such that rotation of the member on its axis causes movement of the image of the light source. An optical connector characterized in that it is formed in. 6. An optical connector according to claim 4 or claim 5, characterized in that the two cylindrical transparent members are provided in substantially aligned spaced relationship. 7. The optical connector according to claim 6, wherein adjacent ends of the two cylindrical transparent members have surfaces formed at an acute angle with respect to the axis of each member.