| 摘要 |
PURPOSE:To make oscillation wavelengths constant by a method wherein the increase of temperature of a laser element is blocked by thermally couple a Peltier element with the laser element. CONSTITUTION:The peltier element 12 thermally coupled with the semiconductor laser element 1 and a control circuit 13 which controls the drive current for the Peltier element 12 are added. When the temperature of the laser element 1 increases, the impressed current to the laser element 1 increases. Since this current is given to the control circuit 13 via a resistor R1, the current flowing into the Peltier element 12 increases, and thereby the cooling effect for the laser element 1 is enhanced. Thus, even when the laser element 1 is increasd in temperature, the cooling effect by the Peltier element 12 is enhanced, and accordingly the temperature increase of the laser element 1 is blocked. Therefore, oscillation wavelengths can be made constant. |
