High power femtosecond laser with adjustable repeat frequency in accordance with scanning speed

摘要

A scanning method with a laser system, the method including the steps of: generating femtosecond seed pulses (211) by means of an oscillator (100, 100 '); extend a duration of the seed pulses by means of an extender (200, 200 '); amplifying extended seed pulses (212) by an amplifier (300, 300 ') in laser pulses (213) with a regenerative amplifier (300) comprising extreme mirrors (321, 322, 323, 324); compensating a group delay dispersion of the laser pulses in the range of 5,000-20,000 fs2 with a dispersion compensator between said amplifier end mirrors; emit the amplified laser pulses (213) from the amplifier by means of an electro-optical modulator (330); compressing the extended laser pulses amplified in laser pulses of femtoseconds (214) with a compressor; concentrate the laser pulses at a focal point in a target area with a scanning laser delivery system; scan the focal point with a scanning speed in the target area with the scanning laser delivery system; change the scanning speed using a processor of the scanning laser delivery system; and adjust the repeat frequency according to the scan speed modified with a repeat frequency controller; wherein the laser system is configured to emit a laser beam with a repetition frequency in a range of 10 kHz to 20 MHz, and to emit the laser beam with an output power greater than 0.1 W.