柱透镜被广泛运用于准直半导体激光光束,而普通圆柱透镜准直能力并不高,为了克服这一不足,提出一种新的柱透镜结构：双半圆柱透镜(DHCL);基于光线传输理论导出该结构柱透镜准直激光光束的基本公式并给出数值模拟的结果。理论分析和数值模拟均表明：在用于准直半导体激光器输出光束方面,双半圆柱透镜突破了普通圆柱透镜在最佳准直时对透镜材料折射率的限制,提高了结构设计和材料选择的灵活性;特别是在高折射率条件下,双半圆柱透镜对光束的准直能力远远超过了普通圆柱透镜。理论上可以将半导体激光光束快轴方向发散角压缩到0.1 mrad的量级。

Cylindrical lenses have been widely used for collimating laser diode beam, but the collimating performance is usually not high. A new collimating element-double half-cylindrical lens (DHCL) was proposed. The theoretical expressions of the collimated beam of a DHCL are derived by transmission theory, and the numerical results are also given. Both theoretical and numerical results indicate that a DHCL can be made from the high refractive index material but a normal cylindrical lens cannot, and the collimating performance of a DHCL is much better than that of a normal cylindrical lens. The divergence angle of the collimated beam could be as small as 0.1 mrad.