【作者】 梁炎锋；

【导师】 左保军；

【作者基本信息】 哈尔滨工业大学 ， 光学工程， 2011， 硕士

【摘要】 无热化设计效果检测仪是检测红外光学系统的无热化设计效果是否符合要求的设备。本文进行无热化设计效果检测仪中自动调焦系统的研究,其自动调焦系统由红外成像探测器、位移控制组件、信号处理电路和计算机控制软件组成,控制软件由图像处理模块、运动控制模块、自动调焦模块和无热化检测模块组成。分别对空间域、信息域和频域中的自动聚焦算法进行了理论研究。针对于红外图像的特点,以检测仪在不同条件下采集的三组红外图像作为分析对象,对各种自动聚焦算法的性能进行了研究。基于差分绝对值之和(SMD)算子和拉普拉斯算子的自动聚焦算法由于实时性、稳定性和准确性较好,分别作为检测仪粗调焦和细调焦的自动聚焦算法。研究并解决了无热化设计效果检测仪系统自动调焦的实现中的一系列关键技术,包括聚焦位置的搜索算法、最佳调焦区域的划分、自动调焦策略和调焦曲线拟合等。提出了一种图像调焦区域划分的方法,该方法首先对调焦图像利用区域生长的方法进行目标识别,再将识别出来的目标区域作为调焦运算区域,提高了自动调焦的精度和速度。设计了无热化设计效果检测仪的系统控制软件。根据检测仪的硬件组成,分别实现了温度调节系统和位移控制组件的控制、红外成像探测器图像的采集和处理、自动调焦以及无热化设计效果检测等功能。在进行图像采集和预处理时,根据无热化测试效果检测仪采集的图像的特点,提出了一种基于自适应阈值的图像增强方法,该方法根据图像本身的亮度生成灰度转换函数,对不同响应度的图像均有良好的增强效果。系统软硬件安装完成后,针对无热化设计效果检测仪需要使用的短波、中波、长波红外成像探测器以及多种检测目标,进行了多次系统实验。实验表明,系统的各个模块运行正常,均能正确实现自动调焦以及设计要求的其他各项功能。最后进行了运动控制模块定位精度、自动调焦重复性误差和自动调焦精度测试,各项指标均符合设计要求。更多还原

【Abstract】 The Effect of Athermalization Tester was an equipment that used to measure whether the effect of IR optical system’s athermalization met the requirement. In this paper, auto-focusing system for the Effect of Athermalization Tester was researched, which was composed by the infrared image detection system, position controlling component, signal processing circuit and controlling software. The controlling software was make up by the image processing module, the motion control module, the auto-focus module and the athermalization testing module.The automatic focusing algorithms on spatial domain, information domain and frequency domain were researched. According to the features of the infrared image, performances of many auto-focusing algorithms were researched, using there groups of infrared images of the Effect of Athermalization Tester that were gathered from different conditions as researching candidates. Auto-focusing algorithms based on Sum Modulus Difference(SMD) operator and Laplacian operator were used as cursory focusing algorithm and accurate focusing algorithm, because of their well real-time performance, high stability and accuracy. Some key technologies and problem in system auto-focusing realization, such as system image preprocessing, focus strategy, focus point searching algorithm, the division of image focusing region, and the focus curve fitting, were researched and solved. An image focusing region divided algorithm was proposed to improve the focusing accuracy and speed, which identified the target of the focus image using region growing at first, then used the identified target region as operating focus region.The software of the Effect of Athermalization Tester was designed. According to the hardware of the tester, the thermo-regulating system and position controlling component controlling, infrared image acquisition and processing, auto-focusing, and effect of athermalization measuring were achieved. During image acquisition and preprocessing, an image enhanced method based on adaptive threshold was proposed according to different responsiveness of the system image, which generated gray scale transferring function based on the image brightness.When system hardware and software were installed completely, experiments of the Effect of Athermalization Tester were conducted with infrared detectors of short wave, medium wave and long wave, and a variety of targets, which the system was required to use. Experiments proved that every module of the tester run properly, and the system implemented auto-focusing and other required functions correctly. Finally the locating accuracy of the motion controlling module, the auto-focusing repeatability accuracy and the auto-focusing accuracy were measured. According to the testing result, all of the there performance parameters were meet to the design requirements.更多还原