嵌入式视频显微镜自动调焦控制系统设计  

Design of auto focusing control system of embedded video microscope

作　　者：许功元 胡斌梁[1,2] 康辉民 刘艳余[1,2] 

机构地区：[1]湖南科技大学机电工程学院,湖南湘潭411201 [2]湖南科技大学机械设备健康维护湖南省重点实验室,湖南湘潭411201

出　　处：《传感器与微系统》2017年第12期71-74,77,共5页Transducer and Microsystem Technologies

基　　金：国家自然科学基金资助项目(61272196);湖南省教育厅重点项目(15A063);湖南省自然科学基金资助项目(2017JJ2090);湖南省研究生科研创新资助项目(CX2016B550)

摘　　要：针对视频显微镜手动调焦效率低、精度差、难以得到最佳显微图像的现状,设计了一种基于嵌入式开发和Matlab数字图像处理的自动调焦控制系统。通过在显微镜调焦、变倍手轮和光照调节处添加精密传动机构,并由单片机电路控制部分实现计数脉冲的获取和电机的控制;所获序列显微图像经电荷耦合器件(CCD)镜头传至PC系统,并由Matlab图像处理软件对其进行清晰度判定,结合设计的'取均值'约束二次调焦的变步长自动搜索算法,以寻找最清晰显微图像,从而完成自动调焦。实验表明:系统可完全取代传统手动调焦操作,且精度更高,在细分驱动条件下,调焦和变倍过程的最小精度可达到1μm。Aiming at the situation of low efficiency and poor precision of manual focusing of video microscope,difficult to get the best microscopic image,an automatic focusing control system based on embedded development and Matlab digital image processing is designed. Through adding precise transmission mechanism to the microscope focus hand wheel and zoom hand wheel and light adjustment,the single-chip circuit control part realizes the counting pulse acquisition and the motor control. Acquired sequence of microscopic images are transmitted to PC through charge coupled device（ CCD） camera,and the Matlab image processing software determine its clarity.Combined with the designed ＇take the mean＇ to adjust the secondary focus of the variable step size automatic search algorithm to find the most clearest microscopic images,thus complete the auto focusing process. The experiment shows that the system can completely replace the traditional manual focusing operation with higher precision. In the subdivision drive conditions,the process of focusing and zooming can reach 1μm of the minimum precision.

关 键 词：视频显微镜 传动机构 单片机 图像处理 自动调焦 

分 类 号：TH742[机械工程—光学工程] TP271[机械工程—仪器科学与技术]