A Shack–Hartmann sensor nonintrusive measurement for the temperature profile in a heat-capacity neodymium-doped glass rod is proposed. This technique is possible because the optical path length of the rod changes with temperature linearly over a wide range. The temperature change of the solid-state laser rod is often recorded by using a thermocouple, thermal camera, or phase-shifting interferometer. Based on an analysis of temperature-induced changes in length and index of refraction, we can get the temperature profiles from the wavefront reconstructions in real time. The results suggest the Shack–Hartmann sensors could replace microbolometer-based thermal cameras and phase-shifting interferometers for dynamic temperature profiles in heat-capacity laser rods with particular advantages. A strange temperature chaos of the Nd:glass rod just after the pump cycle is discovered.
© 2007 Optical Society of America
Instrumentation, Measurement, and Metrology
Original Manuscript: October 10, 2006
Revised Manuscript: December 7, 2006
Manuscript Accepted: January 9, 2007
Published: May 1, 2007
Xiaobo Wang, Xiaojun Xu, Qisheng Lu, and Fengjie Xi, "Shack-Hartmann wavefront sensor measurement for dynamic temperature profiles in heat-capacity laser rods," Appl. Opt. 46, 2963-2968 (2007)