JPH06307983A - Evaluation method for optical waveguide module - Google Patents

Abstract

PURPOSE:To evaluate various characteristics of an optical waveguide module accurately by coupling the optical waveguide module with a plurality of measuring instrumeruts using couplers. CONSTITUTION:Connector terminal 2 of an optical waveguide module 1 is connected with one end 5 of a coupler 4 and branch optical fibers 6a-6d are connected, on the branch side of the coupler 4, with measuring instruments 7-10. A personal computor 13 is connected with the measuring instruments 7-10 and a device board 12 through a GP-IB 15. An output from the optical waveguide module 1 is branched by the coupler 4 and fed to the measuring instruments 7-10 and automatic measurement is carried out under control of the personal computor 13. Reflection on the coupler 4 is negligible and various characteristics of the optical waveguide module 1 can be measured automatically and accurately.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for evaluating an optical waveguide module.

[0002]

2. Description of the Related Art As a conventional evaluation method for an optical waveguide module, a manual measurement method as shown in FIG. 3 is known. This is because each evaluation item, such as optical fiber output, light receiving sensitivity, wavelength characteristics, etc., is measured by a person using a measuring instrument (optical spectrum analyzer 7, laser light source 8, IL curve tracer 9, reflectometer 10, etc.). The output of the optical waveguide module 1, which is a physical product, is input and measured for each evaluation item.

However, in this manual measurement, a person measures the output end of the optical waveguide type module 1 with the measuring instruments 7 to 7 for each measurement.
It takes time to connect and switch to 10. Further, since the measurement is also read and recorded by a person, there is a problem that it takes time and at the same time, one or two dedicated measurement personnel are required.

Therefore, an evaluation method based on automatic measurement of the optical waveguide type module shown in FIG. 4 is used. In this evaluation method, the output of the optical waveguide module 1 is switched to each of the measuring devices 7 to 10 by using the optical path switching device 14 to measure each evaluation item. The measuring devices 7 to 10 and the device board 1 are measured.
2. GP-IB (General Purpose In
An automatic measurement is possible by connecting the personal computer 13 via the terface bus 15). On the PC 13,
Each measurement data is collected while controlling the timing of measurement by the optical path switching time of the optical path switch 14 (several tens of msec).

[0005]

However, in the conventional automatic measuring method shown in FIG. 4, a part of the output of the optical waveguide type module 1 is reflected by the internal reflection of the optical path switching device 14, and the optical waveguide type module 1 is thus reflected. Then, part of the reflected light returns to the semiconductor laser mounted in the optical waveguide module 1. At this time, the oscillation of the semiconductor laser becomes unstable, the wavelength fluctuates, and a kink occurs, which makes it impossible to perform accurate evaluation.

Further, in measuring the return loss of the optical waveguide module 1 (the amount of transmitted light reflected and returning), if there is an optical path switching device 14, the reflection of the optical path switching device 14 causes a dynamic range of 30 dB or more. There was a problem that it became impossible to measure the return loss of.

Further, there is a problem that the optical path switching time by the optical path switch 14 is several tens of msec, and the measurement timing of the control system must be controlled, and the measurement software becomes complicated.

An object of the present invention is to solve the above-mentioned drawbacks of the prior art, to enable accurate measurement of IL characteristics (kink measurement, slope efficiency measurement) and wavelength characteristics, and to provide a return loss with a wide dynamic range. It is to provide a novel optical waveguide module evaluation method that enables measurement. Another object of the present invention is to provide an optical waveguide module evaluation method capable of high-speed automatic measurement and significantly reducing the evaluation man-hours.

[0009]

A method of evaluating an optical waveguide module according to the present invention is a semiconductor laser for transmitting information signal light, and the information signal light transmitted from this semiconductor laser is guided and combined. An optical waveguide for wave propagation, an optical fiber coupled to the optical waveguide for transmitting and receiving signal light to and from a counterpart module, and a transmission signal light from the counterpart module from the optical fiber via the optical waveguide. In an optical waveguide type module having a light receiving element for receiving, one end of a coupler is connected to an optical fiber, and a plurality of branch ends of the coupler are connected to various measuring instruments, respectively. The output information signal light is branched by the coupler, and various characteristics of the optical waveguide type module are measured by a measuring instrument.

Further, in the optical waveguide type module evaluation method of the present invention, a control device such as a personal computer is connected to the measuring instrument, and various characteristics of the optical waveguide type module are automatically measured using the control device. It was done.

[0011]

The output light of the optical waveguide module is branched by the coupler, and the branched light is input to a measuring instrument such as an optical spectrum analyzer to measure various characteristics of the optical waveguide module. In measuring the light receiving sensitivity of the optical waveguide module, light is input from the measuring instrument to the optical waveguide module through the coupler.

When performing automatic measurement, the control device controls the operation of the measuring device.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of an optical waveguide module evaluation method of the present invention will be described below with reference to the drawings.

First, an example of the optical waveguide type module which is the object to be measured will be described with reference to FIG.

Semiconductor laser 21 of optical waveguide type module
The laser light emitted from is coupled to the core portion 23 of the optical waveguide 20 by the coupling lens 22, propagates through the core portion 23, and is transmitted from the optical fiber 3 to the counterpart module via the optical fiber coupling portion 24. Has become.

On the other hand, the signal light from the other module is
The light enters from the optical fiber 3, propagates through the core section 26 of the receiving system by the optical multiplexer / demultiplexer 25, is reflected by the mirror 27, changes the optical path, and is received by the photodiode 28.

Next, a method of measuring various characteristics of the above optical waveguide type module will be described with reference to FIG. As shown in the figure, the optical waveguide module 1 is attached to a device board 12 for driving it. Further, the connector terminal 2 of the transmitting / receiving optical fiber 3 of the optical waveguide module 1 is connected to one end 5 of the coupler 4. The coupler 4 in the illustrated example is (1
X4) It is a coupler, and the terminals of the branched optical fibers 6a to 6d on the branch side of the coupler 4 are respectively connected to the optical spectrum analyzer 7, laser light source 8, IL curve tracer 9 and reflectometer 10 which are measuring instruments. . Furthermore,
Connect each measuring instrument 7-10 and device board 12 to GP-IB1.
Connect to PC 13 via 5. Since a measuring instrument for outputting measurement data to the outside usually has a GP-IB terminal, a personal computer having an interface for GP-IB is used for automatic measurement.

The output signal of the optical waveguide module 1 is input from the connector terminal 2 to the coupler 4, and each branched optical fiber 6
It is branched into a to 6d and input to each measuring device 7 to 10. The optical spectrum analyzer 7 measures the wavelength (spectrum) characteristic of the light input from the branch optical fiber 6a. Similarly, the IL curve tracer 9 measures the optical output, kink, slope efficiency, etc. of the optical waveguide module 1 from the input signal from the branch optical fiber 6c.

The reflectometer 10 is a device for measuring the return loss of the optical waveguide module 1, and when the reflectometer 10 is operated, the operation of the semiconductor laser 21 mounted on the optical waveguide module 1 is stopped. Need to

The laser light source 8 measures the light receiving sensitivity of the optical waveguide module 1. Here, when the oscillation wavelength (for example, 1.3 μm) of the semiconductor laser 21 mounted on the optical waveguide type module 1 and the reception wavelength of the light receiving element (photodiode) 28 mounted on the optical waveguide type module 1 are equal, The wavelength of the laser light source 8 becomes equal to the wavelength of the semiconductor laser 21 of the optical waveguide module 1. At this time, the laser light of the optical waveguide module 1 enters the laser light source 8 and the laser light source 8 becomes unstable. Therefore, the operation of the semiconductor laser 21 mounted on the optical waveguide module 1 is stopped and the light receiving sensitivity is measured.

On the other hand, the oscillation wavelength (for example, 1.3 μm) of the semiconductor laser 21 mounted on the optical waveguide module 1,
When the reception wavelength (for example, 1.5 μm) of the light receiving element 28 mounted on the optical waveguide module 1 is different, the wavelength of the laser light source 8 is naturally the same as the reception wavelength of the light receiving element 28 mounted on the optical waveguide module 1. Since they are the same, the semiconductor laser 21 mounted on the optical waveguide module 1 may be in an operating (transmitting) state. However, in this case, it is better to provide the input portion of the laser light source 8 with the filter 11 that cuts the wavelength of the semiconductor laser 21 mounted on the optical waveguide module 1.

The personal computer 13 controls the operation of the semiconductor laser 21 of the optical waveguide type module 1 through the device board 12 and controls the operation of each of the measuring instruments 7 to 10, so that the optical waveguide type module 1 is controlled. The automatic measurement of the characteristics of is performed. Further, since the coupler 4 is used instead of the optical path switcher used in the conventional automatic measurement, the problem of reflection due to the optical path switcher can be almost ignored, and the IL characteristics, wavelength characteristics, return loss, etc. Can be evaluated accurately. Also, the dynamic range in the return loss measurement of the optical waveguide module is 40 dB.
The above is possible.

The decrease in the amount of light due to the branching of the coupler 4 can be measured first and then corrected by software on the personal computer 13 for accurate light output measurement and return loss measurement.

In the above embodiment, the (1 × 4) coupler 4 is used, but if there are not many evaluation items for the optical waveguide module, the number of coupler branches may be increased for measurement. Further, not only the optical waveguide type module but also the passive module (waveguide, optical multiplexer / demultiplexer) can be similarly evaluated.

[0025]

According to the present invention, the following effects are exhibited.

(1) Since the output light of the optical waveguide module is branched by the coupler and input to each measuring device, reflection inside the coupler can be ignored, and therefore, in the return loss measurement of the optical waveguide module. The dynamic range can be increased.

Further, since the reflected light returning to the semiconductor laser mounted on the optical waveguide type module can be made negligibly small by using the coupler, the semiconductor laser mounted on the optical waveguide type module becomes stable and I- L characteristics (kink, slobe efficiency, etc.) can be measured accurately. Further, the oscillation wavelength of the semiconductor laser becomes stable, and the characteristics of the optical waveguide module can be evaluated accurately.

(2) Further, since automatic measurement can be easily performed by a control device such as a personal computer, the number of evaluation steps can be greatly reduced. Furthermore, the complicated control in the conventional automatic measurement such as the optical path switching timing is not required, and the automatic measurement can be performed with simple control software.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing an embodiment of an optical waveguide module evaluation method according to the present invention.

FIG. 2 is a configuration diagram showing an example of the optical waveguide module in FIG.

FIG. 3 is a configuration diagram showing a conventional optical waveguide type module evaluation method by manual measurement.

FIG. 4 is a configuration diagram showing a conventional optical waveguide type module evaluation method by automatic measurement.

[Explanation of symbols]

 1 Optical Waveguide Module 2 Connector Terminal 3 Optical Fiber 4 Coupler 5 Connector (One End of Coupler) 6a to 6d Branch Optical Fiber 7 Optical Spectrum Analyzer 8 Laser Light Source 9 IL Curve Tracer 10 Reflectometer 11 Filter 12 Device Board 13 Personal Computer 15 GP-IB 20 Optical waveguide 21 Semiconductor laser 22 Lens 23 Core part 24 Optical fiber coupling part 25 Optical multiplexing / demultiplexing part 26 Core part 27 Mirror 28 Photodiode

[Procedure amendment]

[Submission date] October 19, 1993

[Procedure Amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0028

[Correction method] Change

[Correction content]

(2) Further, since automatic measurement can be easily performed by a control device such as a personal computer, the number of evaluation steps can be greatly reduced. Furthermore, the complicated control in the conventional automatic measurement such as the optical path switching timing is not required, and the automatic measurement can be performed with simple control software.

[Procedure Amendment 2]

[Document name to be amended] Statement

[Name of item to be corrected] Brief description of the drawing

[Correction method] Change

[Correction content]

[Brief description of drawings]

FIG. 1 is a configuration diagram showing an embodiment of an optical waveguide module evaluation method according to the present invention.

FIG. 2 is a configuration diagram showing an example of the optical waveguide module of FIG.

FIG. 3 is a configuration diagram showing a conventional optical waveguide type module evaluation method by manual measurement.

FIG. 4 is a configuration diagram showing a conventional optical waveguide type module evaluation method by automatic measurement.

[Explanation of Codes] 1 Optical Waveguide Module 2 Connector Terminal 3 Optical Fiber 4 Coupler 5 Connector (One End of Coupler) 6a to 6d Branch Optical Fiber 7 Optical Spectrum Analyzer 8 Laser Light Source 9 IL Curve Tracer 10 Reflectometer 11 Filter 12 Device board 13 Personal computer 15 GP-IB 20 Optical waveguide 21 Semiconductor laser 22 Lens 23 Core part 24 Optical fiber coupling part 25 Optical multiplexing / demultiplexing part 26 Core part 27 Mirror 28 Photodiode

[Procedure 3]

[Document name to be corrected] Drawing

[Name of item to be corrected] Figure 2

[Correction method] Change

[Correction content]

[Fig. 2]

Claims (2)

[Claims] 1. A semiconductor laser for transmitting information signal light, an optical waveguide for guiding and multiplexing / demultiplexing the information signal light transmitted from this semiconductor laser, and a partner side coupled with this optical waveguide. In an optical waveguide type module having an optical fiber for transmitting and receiving a signal light to and from a module, and a light receiving element for receiving a transmission signal light from the counterpart module from the optical fiber through the optical waveguide, While connecting one end of the coupler to the optical fiber,
A plurality of branch ends of the coupler are respectively connected to various measuring instruments, the information signal light outputted from the optical fiber of the optical waveguide type module is branched by the coupler, and the measuring instruments are used for various optical waveguide type modules. A method for evaluating an optical waveguide module, characterized in that the characteristics are measured. 2. The optical device according to claim 1, wherein a control device such as a personal computer is connected to the measuring device, and various characteristics of the optical waveguide type module are automatically measured by using the control device. Waveguide module evaluation method.