【作者】 王杰；

【导师】 徐海松； 余飞鸿；

【作者基本信息】 浙江大学 ， 工程硕士（专业学位）， 2020， 硕士

【摘要】 机器视觉系统由硬件部分和软件部分构成,硬件主要包括工业相机、光源、光学镜头和图像采集系统。其中光学镜头的成像质量影响着最终获取图像的清晰度和分辨率。本文通过学习文献资料,阐述了机器视觉在国内外的发展现状以及机器视觉镜头的研究现状,在此基础上结合图像传感技术的发展现状,设计了几款机器视觉镜头及其光学系统:论文设计完成一款大视场连续变倍物方远心镜头,放大倍率范围0.5x-1.0x,最大可匹配4/3英寸图像传感器。创新性的提出了利用光学设计软件中的虚拟透镜构建变焦距系统初始结构的方法。利用光学设计软件中的虚拟透镜模拟变倍系统的变倍过程,可初步确定变倍系统中各组份的焦距以及各组分之间在不同放大倍率情况下的间隔,再用实际镜片代替虚拟透镜,即可得到光学系统的初始结构。在构建的初始结构的基础上进行了优化设计,并在完成光学系统的公差分析及凸轮曲线设计后进行了生产与加工。搭配自主研发的工业相机及配套软件系统进行尺寸测量实验,证明了所设计的连续变倍物方远心光学系统测量数据具有可信度和可重复性。论文设计完成一款高变倍比超短尺寸连续变倍数码显微镜,放大倍率范围0.7x-5.6x,工作距离为100mm,但光学系统总长仅130mm。与传统光学显微镜相比,数码显微镜将观察对象直接成像于图像传感器表面,而无需考虑目视光学系统的设计,简化了显微镜光学系统结构,降低了显微镜光学系统加工的难度和生产成本;同时数码显微镜光学系统结合了光学镜头与图像传感技术的优势,具有连续可调的放大倍率与良好的成像质量。在完成高变倍比超短尺寸连续变倍数码显微镜的光学设计后,对整个系统进行了公差分析,并对不同情况下系统的凸轮曲线进行分析,为日后的生产和加工提供了理论设计基础。论文设计完成基于光学镜头移动的多共轭距倍率连续可调便携式数码显微镜光学系统。从变倍系统最原始的光学变倍设计原理出发,从理论上分析了光学系统实现连续变倍的条件以及能够实现的最高放大倍率。基于光学镜头移动的多共轭距倍率连续可调便携式数码显微镜光学系统主要由光学镜头、硬件电路和机械结构组成。所设计的光学镜头焦距15mm,工作距离覆盖25mm-97mm,能够实现0.2x-2.2x连续变倍;电路部分由主控电路板和照明电路板组成;机械部分包括光学镜头机械结构设计和整个系统机械结构设计。利用移动光学镜头的方法实现变倍,在保证光学系统成像质量的同时,最大程度地简化了光学系统的结构。论文还设计完成基于图像传感器移动的多共轭距倍率连续可调便携式数码显微镜光学系统。当光学系统的工作距离变化时,通过调整图像传感器的位置实现清晰成像。基于图像传感器移动的多共轭距倍率连续可调数码显微镜光学系统主要由光学镜头、硬件电路和机械结构组成。设计完成四款焦距为3mm、6mm、15mm和23mm的光学镜头。其中焦距15mm的光学镜头完成生产加工,其工作距离覆盖20mm-200mm,可实现0.1x-3.3x连续变倍;电路部分由供电电路板、主控电路板、传感器电路板和照明电路板组成;机械部分包括光学镜头机械结构设计和整个系统机械结构设计。基于图像传感器移动实现变倍的方法,具有可实现放大倍率连续变化,放大倍率线性调节,大变倍比的优点,是目前主流市场的产品所没有的。借助这种思路,本研究有望应用于机器视觉领域需要放大倍率连续快速变化的场合。更多还原

【Abstract】 The machine vision system consists of hardware and software.The hardware mainly includes industrial cameras,light sources,optical lenses and image acquisition systems.The imaging quality of the optical lens affects the resolution of the final acquired image.By studying the literature,this paper expounds the development status of machine vision at home and abroad and the research status of machine vision lenses.Based on this,combined with the development status of image sensing technology,several machine vision lenses and optical systems are designed:The thesis designed a large field-of-view continuous-magnification object-side telecentric lens with a magnification range of 0.5x-1.0x and matched to a maximum of 4/3-inch image sensor.A method for constructing the initial structure of the zoom system using a virtual lens in the optical design software is proposed innovatively.The virtual lens in the optical design software is used to simulate the variable magnification process of the variable magnification system.The focal length of each component in the variable magnification system and the interval between the components under different magnifications can be initially determined.The actual structure of the optical system can be obtained by replacing the virtual lens with an actual lens.Based on the initial structure,the design was optimized.After completing the tolerance analysis and cam curve design of the optical system,the product was produced and processed.The lens is combined with an independently developed industrial camera and supporting software system for size measurement experiments.It is proved that the measured data of the designed telecentric optical system with continuous zoom is reliable and repeatable.The thesis designed a continuous zoom digital microscope with high zoom ratio and ultra-short size.Its magnification range is 0.7x-5.6x,the working distance is 100mm,but the total length of the optical system is only 130mm.Compared with traditional optical microscopes,digital microscopes directly image on the surface of the image sensor without having to consider the design of the visual optical system,which simplifies the structure of the optical system and reduces the processing difficulty and production cost of the microscope optical system.At the same time,the digital microscope optical system combines the advantages of optical lenses and image sensing technology.It has continuously adjustable magnification and good imaging quality.After completing the optical design of the high zoom ratio ultra-short size continuous zoom digital microscope,tolerance analysis of the entire system and analysis of the cam curve of the system in different situations are performed to provid a theoretical design basis for future production and processing.The thesis designed a multi-conjugate distance magnification continuously adjustable portable digital microscope optical system based on optical lens movement.Based on the original optical zoom design principle of the zoom system the conditions for the continuous zoom of the optical system and the highest magnification that can be achieved are analyzed.The multi-conjugate distance magnification continuously adjustable portable digital microscope optical system based on optical lens movement is mainly composed of an optical lens,a hardware circuit and a mechanical structure.The designed optical lens has a focal length of 15mm and a working distance covering 25mm-97mm.which can achieve a continuous zoom of 0.2x-2.2x;the circuit part is composed of the main control circuit board and the lighting circuit board;the mechanical part includes the mechanical structure design of the optical lens and the entire system mechanical design.The method of using a moving optical lens to achieve zooming,while ensuring the imaging quality of the optical system.greatly simplifies the structure of the optical system.The thesis also designed a multi-conjugate distance magnification continuously adjustable portable digital microscope optical system based on image semsor movement.When the working distance of the optical system changes.clear imaging can be achieved by adjusting the position of the image sensor.Designed four optical lenses with focal lengths of 3mm.6mm.15mm and 23mm.Among them,the optical lens with a focal length of 1 5mm completes production and processing.and its working distance covers 20mm-200mm,which can achieve continuous zooming of 0.1x-3.3x.The circuit part is composed of a power circuit board,a main control circuit board,a sensor circuit board and a lighting circuit board.The mechanical part includes the mechanical structure design of the optical lens and the mechanical structure design of the entire system.The method of achieving zooming based on the movement of an image sensor has the advantages of enabling continuous changes in magnification,linear adjustment of magnification,and large zoom ratios,which are not available in current mainstream market products.With this thinking,this research is expected to be applied to the occasions where the magnification needs to be continuously and rapidly changed in the field of machine vision.更多还原