Thermal lensing compensation objective for high power lasers

Athermalization of focusing objectives is a common technique for optimizing imaging systems in infrared where thermal effects are a major concern. The athermalization is generally done within the spectrum of interest and not generally applied to a single wavelength. By applying athermalization techniques to a laser system, a significant reduction in thermal lensing of the laser system can be realized. We describe a passive method minimizing thermal lensing of high power lasers.