中文摘要：

基于基尔霍夫衍射积分理论,分别推导涡旋光斜入射轴棱锥与凸透镜后的衍射光场表达式.提出一种利用轴棱锥检测光束拓扑电荷数信息的简单可行方案,并将此方案与凸透镜聚焦斜入射涡旋光方案进行对比.研究结果表明：应用轴棱锥聚焦斜入射涡旋光检测拓扑电荷数信息的方式无需对检测点进行严格定标,实际检测工作中该方案更具备灵活性,适用性也更为广泛.通过对设计实验进行验证,实验与理论基本吻合.

英文摘要：

Based on Kirchhoff diffraction integral theory,the expressions of diffraction field after the axicon and convex lens that illuminated by an oblique vortex beam are derived.A simple and feasible method for detecting topological charge number by using an axicon is proposed.We compare this method with that of using convex lens,results show that there is no need to fix detection point strictly by using an axicon.In practice,this method shows more flexibility and applicability.Experiments are designed to verify the researches.Experimental results are in good agreement with theoretical predictions and numerical simulation.