Rod-imaging unstable resonators with super-Gaussian mirrors

The new rod-imaging unstable resonator configuration that we have recently introduced is theoretically analysed and experimentally characterized. A variable reflectivity mirror of super-Gaussian profile has been used as output coupler. Using a pulsed Nd:YAG laser head, which with a traditional stable resonator generates beams of 260 W, an average output power larger than 150 W with a beam divergence of only a few times the diffraction limit has been obtained. It is shown how an intracavity spatial filter can further reduce the beam divergence.

[1]  V. Magni,et al.  Multielement stable resonators containing a variable lens , 1987 .

[2]  V. Magni.  Resonators for solid-state lasers with large-volume fundamental mode and high alignment stability. , 1986, Applied optics.

[3]  Nathalie McCarthy,et al.  Effects of hard apertures on mode properties of resonators with gaussian reflectivity mirrors , 1987 .

[4]  Horst Weber,et al.  Improved resonator design for rod lasers and slab lasers , 1990, Other Conferences.

[5]  Orazio Svelto,et al.  Solid-state laser unstable resonators with tapered reflectivity mirrors: the super-Gaussian approach , 1988 .

[6]  Orazio Svelto,et al.  Lasers with super-Gaussian mirrors , 1990 .

[7]  Orazio Svelto,et al.  Rod-imaging supergaussian unstable resonator for high power solid-state lasers , 1992 .

[8]  Horst Weber,et al.  The near-concentric unstable resonator (NCUR) - an improved resonator design for high power solid state lasers , 1993 .

[9]  Y. Anan'ev,et al.  Influence of the edge effects on the properties of unstable resonators , 1971 .

[10]  P. Laporta,et al.  Unstable laser resonators with super-Gaussian mirrors. , 1988, Optics letters.

[11]  Nathalie McCarthy,et al.  Single transverse mode oscillation from an unstable resonator Nd:YAG laser using a variable reflectivity mirror , 1988 .

[12]  Gianluca Valentini,et al.  Recent developments in laser resonator design , 1991 .

[13]  M. Tanaka,et al.  Negative-branch unstable resonator with a phase unifying output coupler for high power Nd:YAG lasers. , 1990, Applied optics.

[14]  A Piegari,et al.  Optical coatings with variable reflectance for laser mirrors. , 1989, Applied optics.