Abstract

A new type of unstable resonator, suitable for a laser with a large medium cross section and a small or median output coupling, is presented. The resonator configuration, a modification of a negative-branch confocal unstable resonator, is numerically investigated. The basis of the theory is the Fresnel–Kirchhoff integral equation, and the calculations describe a passive resonator. With respect to output mirror tilting, the calculations confirm that the modified negative-branch confocal unstable resonator is less sensitive to mirror misalignments than the conventional negative-branch confocal unstable resonator. Furthermore, the modified resonator improves the beam quality in comparison with the conventional unstable resonator.

© 2006 Optical Society of America

COIL emission of a modified negative branch confocal unstable resonator

Carsten Pargmann, Thomas Hall, Frank Duschek, Karin Maria Grünewald, and Jürgen Handke
Appl. Opt. 46(31) 7751-7756 (2007)

Off-axis negative-branch unstable resonator in rectangular geometry

Carsten Pargmann, Thomas Hall, Frank Duschek, Karin Maria Grünewald, and Jürgen Handke
Appl. Opt. 50(1) 11-16 (2011)

Advantages of negative-branch compared with positive-branch one-dimensional unstable resonators

Koji Yasui and Yushi Takenaka
Appl. Opt. 40(21) 3547-3551 (2001)

Negative-branch unstable resonator Nd:YAG laser

T. F. Ewanizky and J. M. Craig
Appl. Opt. 15(6) 1465-1469 (1976)

Chemical oxygen-iodine laser power generation with an off-axis hybrid resonator

Jürgen Handke, Wolfgang O. Schall, Thomas Hall, Frank Duschek, and Karin M. Grünewald
Appl. Opt. 45(16) 3831-3838 (2006)