| 摘要 |
<P>PROBLEM TO BE SOLVED: To solve the problem that the light quantity of a laser beam emitted from a laser beam source is fluctuated by a temperature change even when control is performed so as to fix laser monitor output since the sensitivity to a temperature of a photodetector for front monitoring changes. <P>SOLUTION: A reference laser power value corresponding to the light quantity of the laser beam generated from the laser beam source 20 at the time of setting it at a reference temperature and driving it by reference laser control output is measured by a power meter 31, and the laser beam source 20 is temperature-adjusted within the temperature range of operation guarantee. When the laser beam source 20 reaches the reference laser power value at each of a plurality of optional temperatures, light receiving output from the photodetector 22 for monitoring which generates the laser monitor output to be fed back to an APC circuit 23 is detected, and a laser monitor output value corresponding to the detected light receiving output is stored as table data for each set temperature. At the time of transmission, setting signals are set in the APC circuit 23 on the basis of the table data. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
