中文摘要：

目前渐变折射率透镜的应用，通常都采用其主轴就是光线传播的光轴（横向应用）的形式，未见主轴垂直光轴应用的纵向应用分析说明。为此进行了相关光学追迹，证明直径中间45％以内光线球差很小。通过数据拟合发现光线在这种情况下满足抛物线函数，对今后DLS快轴准直等工作具有重要意义。

英文摘要：

The application of GRIN rod lens is usually used with its core as optical axis, this is transverse application, and any analyze for vertical application is not seen. After tracing, the aberration is small enough within the middle 45 percent of diameter, and the type of the path is parabola are found. This is important for fast-axis collimation of DLS.