Absorption of laser beam power in optical elements induces thermal gradients that may cause unwanted phase aberrations. In precision measurement applications, such as laser interferometric gravitational-wave detection, corrective measures that require mechanical contact with or attachments to the optics are precluded by noise considerations. We describe a radiative thermal corrector that can counteract thermal lensing and (or) thermoelastic deformation induced by coating and substrate absorption of collimated Gaussian beams. This radiative system can correct anticipated distortions to a high accuracy, at the cost of an increase in the average temperature of the optic. A quantitative analysis and parameter optimization is supported by results from a simplified proof-of-principle experiment, demonstrating the method's feasibility for our intended application.
© 2004 Optical Society of America
(010.1080) Atmospheric and oceanic optics : Active or adaptive optics
(140.3300) Lasers and laser optics : Laser beam shaping
(140.6810) Lasers and laser optics : Thermal effects
(190.4870) Nonlinear optics : Photothermal effects
Ryan Lawrence, David Ottaway, Michael Zucker, and Peter Fritschel, "Active correction of thermal lensing through external radiative thermal actuation," Opt. Lett. 29, 2635-2637 (2004)