Short pulse laser device
A short pulse laser arrangement with, preferably, passive mode-locking, comprising a resonator containing a laser crystal and several mirrors, one of which forms a pump beam coupling-in mirror and one of which forms a laser beam out-coupling mirror, and a multiple reflexion telescope enlarging the resonator length, the resonator in operation having a positive averaged dispersion over a wavelength range concerned; the adjustment of the positive averaged dispersion of the resonator is effected by means of the mirrors of the resonator, at least a few of which are designed as dispersive mirrors.
1. A short-pulse laser arrangement comprising:
a resonator comprising resonator components including a laser crystal, a plurality of mirrors including a pump beam coupling-in mirror, a laser beam out-coupling mirror and a multiple reflection telescope for enlarging an effective length of the resonator, a first set of the resonator components having a positive group delay dispersion;
said plurality of mirrors including dispersive mirrors with a negative group delay dispersion for compensating in part the positive group delay dispersion of the first set of the resonator components;
said resonator in operation having a positive net averaged group delay dispersion over an operating wavelength range and the net averaged group delay dispersion is constant over the operating wavelength range, the resonator in operation generating laser pulses having an energy higher than 200 nJ,
wherein the positive net averaged group delay dispersion of the resonator is in a range between 0 and 100 fs 2 .
2. The short-pulse laser arrangement of claim 1 , wherein the positive net averaged group delay dispersion is in a range between 0 fs 2 and 50 fs 2 .
3. The short-pulse laser arrangement of any one of claims 1 or 2 , wherein the multiple reflection telescope comprises at least one of the dispersive mirrors with the negative dispersion.
4. The short-pulse laser arrangement of claim 3 , wherein all the mirrors of the resonator are the dispersive mirrors with the negative dispersion.
5. The short-pulse laser arrangement of any one of claims 1 or 2 , the resonator comprising a pair of glass wedges with positive dispersion configured to provide a supplementary dispersion fine adjustment.
6. The short-pulse laser arrangement of any one of claims 1 or 2 , wherein the laser arrangement is configured to provide passive mode-locking.
7. The short-pulse laser arrangement of claim 6 , wherein a Kerr-lens mode-locking principle is used for the passive mode-locking.
8. The short-pulse laser arrangement of claim 6 , comprising a saturable absorber positioned and configured to perform the passive mode-locking.
9. The short-pulse laser arrangement of claim 1 , wherein an entirety of the negative dispersion of the resonator is determined only by the dispersive minors with the negative dispersion.
10. The short-pulse laser arrangement of claim 1 , wherein the positive net averaged group delay dispersion is between 0 and 50 fs 2 and is provided over a bandwidth of at least 280 nm.
11. The short-pulse laser arrangement of claim 10 , wherein the positive net averaged group delay dispersion is provided over a bandwidth in a range of 680 nm to 960 nm.