JPH04256378A - Optical element module - Google Patents

Abstract

PURPOSE:To realize high precision and easy assemble due to automatic adjustment of Z-axis direction by providing a cap with a projecting part which projects by a specified dimension to an optical axis direction which connects centers of a micro lens and are optical element. CONSTITUTION:A receptacle 8a having an insertion port 9 for ferrule provided with optical fiber connected with a micro lens 5 is fixed to an optical element 6 which consists of a stem 3 whereon a light emitting (or photosensitive) element 1 is mounted and a cap 4a which is formed by attaching a micro lens 5 to a light output window (or light incidence window). In such an optical element module, the cap 4a is provided with a projecting part 11a which projects by a specified dimension in optical axis direction which connects centers of micro lens 5 and ant optical element 6. For example, a size of the projecting part 11a is decided by light emitting diameter of the micro lens 5 and the light emitting element pellet 1 and the kind of connected fiber. Thereby, it is possible to eliminate the necessity of optical axis adjustment in Z-axis direction, thereby requiring only two axes of X and Y.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical element module for optical communication, and more particularly to a receptacle type optical element module.

0002

2. Description of the Related Art Conventionally, this type of optical element module has had a structure as shown in FIG. These modules consist of an optical element 6 with a microlens and a receptacle 8 on which an optical element pellet is mounted.

[0003]Here, since the optical element is basically the same whether a light-emitting element or a light-receiving element is used, the case of a light-emitting element will be described below.

First, a light emitting element pellet 1 is mounted on a stem 3 through a heat sink 2 using a gold-tin alloy or the like. Furthermore, the cap 4 with the microlens 5 and the stem 3 are resistance welded to form a highly airtight package.

[0005] To attach the receptacle 8 to the optical element 6 with the microlens, the master FC connector 10 inserted into the ferrule insertion opening 9 of the receptacle 8 and the optical axis are adjusted across the three axes of XYZ. Then, resin is injected into the resin joint portion 7 and fixed at the position where the combined optical output with the master FC connector 10 is maximum.

[0006]

[Problems to be Solved by the Invention] In the conventional optical element module described above, the optical element 6 with a microlens,
In order to find the maximum coupling position with the master FC connector 10, it is necessary to adjust the optical axes of the three axes of XYZ. Further, adjustment must be made so that the optical axes of the optical element 6 with a microlens and the master FC connector 10 are not tilted.

[0007] Therefore, it takes a considerable amount of time to find the maximum coupling position with the master FC connector 10, increasing the assembly cost. In other words, there is a drawback that a highly accurate optical element module cannot be obtained.

[0008]

[Means for Solving the Problems] The present invention provides an optical element comprising a stem equipped with a light emitting (or light receiving) element and a cap having a microlens attached to the light output window (or light incidence window). In an optical element module in which a receptacle having an insertion port for a ferrule with an optical fiber to be coupled is fixed, the cap is provided with a convex part that protrudes by a predetermined dimension in an optical axis direction connecting the microlens and the center of the optical element. It is said that

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the present invention will be explained with reference to the drawings.

FIG. 1 is a longitudinal sectional view of one embodiment of the present invention.

The light emitting element pellet 1 is mounted on a stem 3 through a heat sink 2 using a gold-tin alloy or the like. Furthermore, the cap 4a having the microlens 5 and the stem 3 are resistance welded.

[0012] This cap 4a has a different structure from the conventional one,
There is a convex portion 11a on the outside of the microlens 5. The dimensions of this convex portion are determined by the emission diameters of the microlens 5 and the light emitting element pellet 1 and the type of fiber to be coupled. In this embodiment, master FC connector 1
0 is inserted into the receptacle 8a, the distance between the optical reference plane 13 and the tip of the microlens is 1.0±0
．． It is set to 05mm. This is an appropriate distance since the tolerance in the optical axis direction is ±0.1 mm.

[0013] Due to the above-mentioned convex portion 11a, there is no need to perform optical axis adjustment in the Z-axis direction, and only two axes, X and Y, are required.

Therefore, when adjusting the optical axis between the optical element 6 with the microlens and the master FC connector 10, first place the tip of the cap 4a on the adjustment surface 1 of the receptacle.
4, then adjust the two axes, X and Y, to find the position where the maximum coupling with the optical power is achieved.

Then, the resin 12 is used to fix the optical axis, and the optical axis adjustment operation is completed.

A second embodiment is shown in FIG. In the second embodiment, the cap 4b is made thick, and the connecting portion 15 with the receptacle is threaded. At the same time, screw threads are similarly attached to the inner wall of the receptacle 8b. This screw thread defines the distance between the optical element 6b and the fiber end face.

In this case, first, the optical element 6b is inserted into the receptacle 8b while rotating, and the optical element 6b is closed until the rotation stops. After that, fine adjustment is made within the clearance of the thread, and finally it is fixed with resin 12.

In this embodiment, the optical element 6b and the receptacle 8b are not fixed to the XYZ fine adjustment table.
Optical axis adjustment becomes possible easily.

[0019]

As explained above, in the present invention, a convex portion having a predetermined dimension is provided on the optical device package to determine the distance in the optical axis direction, which provides the optimum coupling position between the optical device and the optical fiber. As a result, adjustment in the Z-axis direction can be automatically performed, resulting in the effect that a highly accurate optical element module can be obtained. Also, assembly is easy, reducing the required man-hours by 30%.
It can be reduced to some extent.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing a first embodiment of the present invention.

FIG. 2 is a sectional view showing a second embodiment of the invention.

FIG. 3 is a sectional view showing a conventional example.

[Explanation of symbols]

1 Light emitting element pellet 2 Heat sink 3 Stem 4, 4a, 4b Cap 5 Microlens 6 Optical element 7, 7a, 7b Joint portion 8, 8a, 8b Receptacle 9 Insertion port 10 Master FC connector 11a, 11b Convex portion 12 Resin 13 Receptacle Optical reference plane 14
XY axis adjustment surface 15 of receptacle Connection part

Claims (1)

[Claims] 1. An optical element comprising a stem equipped with a light emitting (or light receiving) element and a cap having a microlens attached to the light output window (or light incidence window), and a ferrule comprising an optical fiber coupled to the microlens. In the optical element module fixed to a receptacle having an insertion opening for the optical element, the cap is provided with a convex part that protrudes by a predetermined dimension in the direction of the optical axis connecting the microlens and the center of the optical element. element module.