Abstract
A new kind of phase change material (PCM) cooled mirror for use in the resonator of high power lasers is proposed. The PCM cooled mirror can minimize the thermal deformation on the reflecting surface effectively. A test setup was designed and the laser-induced thermal deformation of honeycombed PCM cooled mirror was measured at real time. Compared with a solid silicon mirror, it was only 0.45 m at the tenth second of laser irradiation after absorbing 140 W net heat. In addition, the influence of the method of support on the thermal deformation was studied by experiments and showed that a simple support is compatible with a PCM cooled mirror.