| 摘要 |
PURPOSE:To realize a semiconductor-laser wavelength stabilizer having a highly stable oscillation frequency even for a mount by providing a predetermined modulation means, an absorption cell, a photodetector, a lock-in amplifier and a control means. CONSTITUTION:Output beams from a semiconductor laser LD1 are separated in two directions by a beam splitter BS1, and beams having frequency upsilon+fD are projected to an absorption cell CL1 as primary diffracted beams at the time of ON of a SW1. Incident beams are all projected to the absorption cell CL1 at frequency upsilon0 as O-order diffracted beams at the time of OFF of the switch SW1. When beams modulated by an acoustooptic modulator UM1 are projected to the absorption cell CL1, the amount of transmitted beams is modulated and a signal appears in an output. When the signal is converted into an electric signal by a photodetector PD1 and rectified synchronously at frequency fm in a lock-in amplifier LA1, a primary differential waveform is acquired. When the currents of the semiconductor laser LD1 are controlled by a PID controller CT2 and an output from the lock-in amplifier LA1 is locked (controlled) at the center of said primary differential waveform, output beams form the semiconductor laser have stable frequency of upsilons-fD/2. |
