一种基于液体透镜的仿生视觉快速调焦方法

Quick focusing method in bionic vision based on the liquid lens

为了提高仿生视觉系统中调焦方法的实时性,在对基于液体透镜的仿生视觉系统调焦控制方式进行研究的基础上,提出一种改进的快速调焦方法,实现系统焦距快速调节的功能。首先将基于激光位移传感器的主动式调焦结果作为预正焦点的判断准则,然后利用基于Sobel算子的灰度梯度评价函数并结合改进的爬山搜索算法对焦距进行精细调整,最后搭建仿生视觉成像系统实验装置,验证本文方法的准确性及实时性。结果表明,利用提出的快速调焦方法,在调焦过程中对同一场景不同模糊程度24帧图像的处理时间可以达到257 ms,相比于传统的自动调焦方法在速度上有很大提升。

In order to improve real-time focusing in the bionic vision system,an improved fast focusing method based on liquid zoom lens is proposed,which achieves fast adjustment of focal length.Firstly,the active focusing result based on laser displacement sensor is taken as pre-focal judgment criterion.Then the focal length of the system is finely adjusted through the gray gradient evaluation function based on Sobel operator and the improved climbing search algorithm.An experimental device of the bionic vision imaging system was built,and the accuracy and real-time of this focusing control method were verified.Results show that the processing time of this method for 24 images with dif-ferent fuzzy scales under the same scene consumes only 257 ms in the process of focus adjustment,and this method has greatly improved the focusing speed compared with the traditional automatic focusing method.