为了实现热容激光器远场可聚焦性的实时控制,采用角锥棱镜阵列作为准相位共轭反射镜对光束波前进行被动式实时补偿。详细研究了阵列角锥棱镜谐振腔的光学特性,通过优化谐振腔的构型,进行腔内滤波,抑制角锥之间的共轭模式,获得了在保持90％输出能力条件下的单模输出,中心主斑能量集中度提高了约4.5倍,远场可聚焦性与传统的平-凹腔比提高约10倍。结果表明,角锥棱镜阵列谐振腔具有热不灵敏的特性,可显著提高热容激光器的远场聚焦能力。

The output beam profile from a heat capacity laser is instantaneously changing because of the temperature continually rising during laser shots.In order to improve the focusing capability of heat capacity laser and realize real time controlling of the far field spot,a cube corner array(CCA) is used as a quasi-phase conjugate mirror to realize a passive and real time compensation of the wave front error.The compensation capability of a thermal insensitive cavity with a cube corner array was studied in detail.The structure of the cube corner array resonator was optimized by using an intra-cavity filter to reject the conjugation mode between different cube corners.The energy concentration of the single mode with an intra-cavity filter was improved to 90%,approximately 4.5 times of the multi-modes without the intra-cavity filter.The focusing ability of such a CCA resonator was improved about 10 times of a traditional planner-concave resonator.The simulation and experiment results show that the cube corner array cavity is thermal insensitive,which can increase the focusing ability of a heat capacity laser.