由于在经过定位预处理之后的原始虹膜图像中，存在可能干扰定位的多种因素。为了准确、快速地进行虹膜定位，因而对这些因素进行了详细的分析之后，首先采用建立图像边界初始域的2维投影图的方法，将初始域中的各种分布特征和各维的投影特征联系起来；然后利用搜索和交叉方法来得到较好的虹膜边界的初始域，以最终计算出准确的虹膜边界。经过对样本库的比对实验和分析，结果表明，该方法定位的结果准确、快速、鲁棒性较好，而且对预处理过程中采用的不同类型的滤波器并不敏感。

This paper particularly analyzes some factors possibly disturbing iris localization in the iris image through the localizing pre processing. After establishing two dimensional projection of the edge rude field, the paper researches the relation between every dimension projecting characters and the tangled distributing traits in the edge rude field, and then acquires the possible good rude field of iris edge using the way of scout and crossing, finally calculates the exact iris boundary. After the comparing test and the analysis to the iris image database, the result shows that the robust algorithm can quickly and accurately complete iris localization and it is not sensitive to different filters worked on the pre processing of the localization.