部分相干光束照射的透镜轴棱锥获得均匀焦线

Lens-axicon illuminated by a partially coherent beam for generating uniform focal segments

从部分相干光的交叉谱密度函数传输公式出发,推导了高斯谢尔模型(GSM)光束被球差透镜衍射后轴上光强分布的解析公式,并进行了数值模拟和物理分析。结果表明,具有一定束腰宽度和空间相干度的GSM光束经过负球差透镜聚焦后,可以获得轴上光强的均匀分布。通过改变GSM光束的束腰宽度和空间相干度来实现轴上光强均匀分布的方法很简单,转换效率高。

Both backward-type and forward-type lens axicons illuminated by a Gaussian Schell- model （GSM） beam were studied. A numerical calculation was performed to investigate the axial intensity distribution of the focal segment. It is shown that when a backward-type lens axicon is illuminated with an appropriate beam radius and spatial coherence of the incident Gaussian Schell- model beam, one can achieve a focal sgment with uniform axial intensity. The rapid oscillation of the axial intensity can be reduced by the decreasing of spatial coherence. This method is very simple and efficient. A forward-type lens axicon illuminated by a Gaussian Schell- model beam is also investigated.