Inspection method for semiconductor laser device and inspection device for semiconductor laser device

An inspection device for semiconductor laser device configured to inspect a semiconductor laser device integrated with a semiconductor laser, an electroabsorption modulator configured to receive as an input a laser light output from the semiconductor laser, and a photodetector fixed in a single position to detect a laser light intensity of part of the laser light of the semiconductor laser output from the electroabsorption modulator, the inspection device comprising:

• a semiconductor laser power source configured to supply an injection current to the semiconductor laser;
• an electroabsorption modulator power supply configured to supply a reverse bias voltage to the electroabsorption modulator;
• a photodetector power supply configured to supply a reverse bias voltage to the photodetector, and
• an inspection controller configured to acquire a transverse-mode light output characteristic that is a relationship between the injection current to the semiconductor laser and a photocurrent output from the photodetector and to acquire a total light output characteristic that is a relationship between the injection current to the semiconductor laser and a photocurrent output from the electroabsorption modulator while applying the reverse bias voltage to the electroabsorption modulator, and to compare the total light output characteristic with the transverse-mode light output characteristic, thereby to determine whether or not the semiconductor laser device under inspection is abnormal in a transverse mode.

An inspection method for semiconductor laser device adapted to inspect a semiconductor laser device integrated with a semiconductor laser and an electroabsorption modulator configured to receive as an input a laser light output from the semiconductor laser, the inspection method comprising:

• a step of acquiring a transverse-mode light output characteristic that is a relationship between an injection current to the semiconductor laser and a photocurrent output from a photodetector fixed in a single position to detect a laser light intensity of a part of the laser light of the semiconductor laser output from the electroabsorption modulator;
• a step of applying a reverse bias voltage to the electroabsorption modulator and acquiring a total light output characteristic that is a relationship between the injection current to the semiconductor laser and a photocurrent output from the electroabsorption modulator while applying the reverse bias voltage to the electroabsorption modulator;
• a step of comparing the total light output characteristic with the transverse-mode light output characteristic;
• and
• a step of determining whether or not the semiconductor laser device under inspection is abnormal in a transverse mode based on a result of comparing the total light output characteristic with the transverse-mode light output characteristic.