| 摘要 |
According to the invention, a laser pulse train consisting of at least two laser pulses (1,2,3,4,5,6) is fed into a light path extending between a starting and an end point, and a resonator ring (37) is inserted into the light path at a first point (BS 1 ) differing from the end point, which ring closes into itself at said first point (BS 1 ). The length of the resonator ring (37) essentially equals to the product of the separation length between subsequent laser pulses and a rational number in the form of n/m (n and m are positive integers). After dividing the laser pulses that reached the first point (BS 1 ), a predefined fraction of said laser pulses is directed into the resonator ring (37) and is guided along it. The remaining fraction of the laser pulses divided at the first point (BS 1 ) is guided into a segment of the light path that falls beyond the first point and is led to the end point. A detector (35) is arranged at the end point and a physical quantity peculiar to the superposition of the electric fields of the laser pulses guided to the end point is determined by said detector. Finally, the pulse-to-pulse drift of carrier-envelope phase for subsequent laser pulses is determined from the variation of the physical quantity obtained in this manner. |
