JPH06347672A - Laser module - Google Patents

Abstract

PURPOSE:To easily provide large output of an optical fiber of a laser module without lowering the reliability in an element. CONSTITUTION:A semiconductor laser formed on the same semiconductor substrate in an array shape is optically coupled with an optical fiber array 2 arranged at the same pitch, and further, the output of the optical fiber 2 is coupled to one piece of optical fiber 4 using an optical coupler 3. Further, an IC 8 simultaneously driving plural pieces of semiconductor lasers is loaded in the same case 6, and this module is formed so that propagation delay amounts among respective ports become equal. Thus, since the positioning of an optical axis is facilitated, and further, driving current per one piece of semiconductor laser is reduced, the life of the element is prolonged. Further, an input electric waveform becomes equal to an output waveform. Thus, the large output of the optical fiber is provided easily and without lowering the reliability of the element.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laser module for increasing the output of an optical fiber in optical fiber communication.

[0002]

2. Description of the Related Art If the output of an optical transmitter is increased, the applicable range of optical communication can be expanded by increasing the transmission distance and eliminating the need for a highly sensitive receiver. Conventionally, in order to obtain a large output using a semiconductor laser, a method of increasing the driving current of the semiconductor laser or connecting the optical fibers of a plurality of laser modules with an optical coupler has been known. For example, there is a collection of lecture papers of the 3rd Joint Conference of the Institute of Electrical and Information Engineers in 1990 (3rd volume), "Higher performance of semiconductor laser".

[0003]

In the above-mentioned prior art, since there is a limit even if the driving current of the semiconductor laser is increased,
The desired high output may not be obtained, or the life of the semiconductor laser may be shortened by increasing the drive current. Also, even if the optical fibers of multiple laser modules are connected to the optical coupler, it takes time and effort to align the optical axes between the ports,
Since the amount of propagation delay between the ports was different, it was necessary to adjust the fiber length and the phase of the input signal.

An object of the present invention is to solve the above problems and to provide a laser module which can easily obtain a large output of an optical fiber without deteriorating the reliability of the device.

[0005]

In order to achieve the above object, the laser module according to the present invention employs the following means.

(1) Semiconductor lasers formed in an array on the same semiconductor substrate and an optical fiber array arranged at the same pitch are optically coupled, and the output of the optical fiber array is made into one by using an optical coupler. To the optical fiber of.

(2) The ICs for driving a plurality of semiconductor lasers at the same time are mounted in the same case, and the propagation delay amounts between the ports are made equal.

[0008]

According to the above construction, the optical coupling between the semiconductor lasers formed in an array on the same semiconductor substrate and the optical fiber array arranged at the same pitch can be achieved only by aligning both ends. Moreover, the drive current per semiconductor laser can be reduced. Further, by making it so that the propagation delay amount between the ports becomes equal, the phase shift of the pulse between channels does not occur, the input electric waveform and the output waveform become equal, and a large output can be obtained.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of the present invention will be described below with reference to FIG. First, the submount 7 having the 8-channel semiconductor laser array 1 mounted thereon and the IC 8 for driving the semiconductor laser array are fixed by soldering on the upper surface of the mount 9 and connected by wire bonding. Next, the optical fiber array 2 in which the optical fibers are arrayed into 8 channels is embedded in the V-groove guide 5 having the same array pitch as the semiconductor laser array 1, and the optical axis is adjusted with the semiconductor laser array 1. Go and fix to case 6. Further, the 8-channel optical fiber array 2 and one optical fiber 4 protruding outside the case 6 via the V-groove guide 5 are connected to the optical coupler 3. The optical fiber and the optical coupler 3 are connected by fusion.

In this embodiment, a semiconductor laser is used as a light emitting element, but a light emitting diode may be used.

[0011]

According to the present invention, optical coupling between an array of semiconductor lasers and an optical fiber array formed on the same semiconductor substrate is performed by aligning both ends of the arrayed semiconductor laser and the optical fiber array. The remaining channels (in the case of N channels, N-2 channels)
The position adjustment can be performed at once, which is easily possible. Further, each of the arrayed semiconductor lasers can be driven with a small current, and the device life can be extended. Moreover, by adjusting so that a certain output can be obtained, some semiconductor lasers can be made to illuminate, and even if one element does not illuminate, it can be supplemented by the remaining elements, and the life of the module is further increased. It is also possible to extend. Furthermore, since the propagation delay amount between the ports is made to be equal, the input electric waveform and the output waveform are made equal, and high-speed communication can be supported. From the above, a large output of the optical fiber can be easily obtained without deteriorating the element reliability.

[Brief description of drawings]

FIG. 1 is a plan view of an embodiment of a laser module according to the present invention.

[Explanation of Codes] 1 ... Semiconductor laser array, 2 ... Optical fiber array, 3 ...
Optical coupler, 4 ... Optical fiber, 5 ... V groove guide, 6 ... Case, 7 ... Submount, 8 ... IC, 9 ... Mount, 10
… Lead terminals.

Claims (3)

[Claims] 1. A plurality of semiconductor lasers formed in an array on the same semiconductor substrate, and a plurality of optical fibers having the same array pitch as the semiconductor lasers formed in an array on the same semiconductor substrate. In the laser module for optically coupling, the output of the optical fiber array arranged in the plurality is coupled to one optical fiber. 2. The laser module according to claim 1, further comprising an optical coupler for coupling the outputs of the optical fiber array arranged in a plurality into one optical fiber. 3. I for simultaneously driving a plurality of semiconductor lasers
2. The laser module according to claim 1, wherein C is mounted in the same case, and the propagation delay amount between the ports is made equal to each other.