Highly repetitive laser system having a compact design
The invention relates to a highly repetitive laser system operating according to the reproducible amplifier principle. Said system comprises at least one amplified laser medium, a laser resonator provided with at least one resonator mirror and at least one modulator and a pump source, in particular, a laser diode source, which is used to pump the laser medium. The highly repetitive laser system is compact by virtue of the fact that a pulse extensor, having a highly dispersive effect as a result of the structure or material thereof, is integrated into the laser resonator.
1. Laser system according to the principle of the regenerative amplifier, comprising:
an amplifying laser medium,
a laser resonator having at least one resonator mirror and at least one modulator, and
a pump source for pumping the laser medium,
wherein the laser resonator is designed to operate with a repetition rate of greater than 50 kHz and has a pulse stretcher, inside a cavity of the resonator, as a specially designed component, the pulse stretcher having at least one of a structure- or material-related dispersive effect, the pulse stretcher having a minimum 3 rd order dispersion with a maximum 2 nd order dispersion.
2. Laser system according to claim 1 , wherein the pulse stretcher has a block of highly dispersive material.
3. Laser system according to claim 2 , wherein multiple reflections takes place within the block by reflections at interfaces.
4. Laser system according to claim 1 , wherein the pulse stretcher has a Gires-Tournois interferometer or a dispersive layer structure.
5. Laser system according to claim 4 , wherein the pulse stretcher has at least two reflecting surfaces, the surfaces being arranged in such a way that the surfaces are oriented
relative to one another and
at an opening angle
and the laser beam is reflected at least twice at at least one of the surfaces.
6. Laser system according to claim 1 , wherein the laser medium has an inversion life time greater than 1 ms.
7. Laser system according to claim 1 , wherein a femtosecond oscillator for inputting seed pulses, the femtosecond oscillator being formed and arranged in such a way that the seed pulses are femtosecond pulses or picosecond pulses on input into the laser resonator.
8. Laser system according to claim 1 , wherein an electro-optical switching element as modulator.
9. Laser system according to claim 1 , wherein a pulse compressor is outside the laser resonator.
10. Laser system according to claim 9 , wherein the pulse compressor has a dispersive grating having less than 1700 lines/mm.
11. Laser system according to claim 1 , wherein the pump source is a laser diode.
12. Laser system according to claim 2 , wherein the highly dispersive material is at least one of a SF57 glass, SF10 glass or BK7 glass.
13. Laser system according to claim 5 , wherein the opening angle is adjustable.
14. Laser system according to claim 6 , wherein the laser medium is a Yb:glass or a Yb:crystal.
15. Laser system according to claim 9 , wherein the pulse compressor has a dispersive grating having less than 1200 lines/mm.
16. Laser system according to claim 4 , wherein the dispersive layer structure is used as a folding mirror.
17. Laser system according to claim 9 , wherein a relationship of the pulse compressor outside the laser resonator is according to a Treacy design.