| 摘要 |
<p>PROBLEM TO BE SOLVED: To easily correct an optical output change, which is incidental to deterioration in the lapse of time, from the exiting end of electrical current supply to a semiconductor laser by correcting the current supply so that the optical output is corrected through a command from a command preparing device for output correction. SOLUTION: A current supply to semiconductor laser 1 is set by a constant current setting unit 10. The supply current to the laser 1 is outputted, in accordance with the set value, by a constant-current regulated power circuit 4. With an optical output measuring unit 6, the output is measured of the optical fiber 2 connected to the laser 1. With this measurement data stored by a storing means 70a, 70b, 70c, the correction coefficient of the optical output is calculated from the measurement by a calculating means 70e. Then, the supply current to the laser 1 is corrected, by a controller 70 on the command from a command preparing device 9 for output correction, so that the optical output has the corrected value. The calculating means of the controller determines the threshold current Ith of the semiconductor laser from the data of a data holding means by using formula I (wherein, P is optical output; and IL, IM are each preset supply current).</p> |
