METHOD FOR MEASURING DURATION OF FEMTOSECOND LASER PULSES Russian patent published in 2018 - IPC G01J11/00 

FIELD: optics.

SUBSTANCE: invention relates to nonlinear optics. Method for measuring duration of femtosecond laser pulses involves creating with the help of an interferometer of two copies of the investigated femtosecond laser pulse, which are directed to a nonlinear crystal that provides for the simultaneous generation of second-harmonic radiation from one of the pulses and the emission of the total frequency from both copies, and registration of intensity distribution that occurs when the second harmonic beam interferes with the pulse and the total frequency beam. Measure the ratio of the intensity of the total frequency and the second harmonic of two copies of the femtosecond laser pulse tested to the intensity of the total frequency and the second harmonic of two copies of 100 fs duration. By calibration linear dependence of this ratio, the duration of the investigated femtosecond laser pulses is found.

EFFECT: increase in accuracy of measuring the duration of femtosecond laser pulses in the range below 100 fs.

3 cl, 2 dwg