投影机镜头的MTF实时检测系统

目前还没有标准的方法来检测投影机镜头的MTF,为此我们提出了一种基于图像分析的投影机镜头MTF实时测试系统.本系统使用CCD作为成像接收器,采用基于图像分析的方法,通过分析单个像素成像同时获得投影镜头子午和弧矢两个方向上的调制传递函数(MTF).阐述了整个测试系统的构造及理论框架,着重分析了系统参数标定的重要性以及如何正确地进行系统参数标定;全面分析了影响测试结果的因素以及如何正确快速地修正噪声的影响.检测了质量合格与质量不合格的投影机镜头,并将结果同设计值的进行比较,实验结果表明了本系统及其处理方法的有效性.

Real-time MTF Measurement System for Projection Lens

There is no standard method for the Modulation Transfer Function (MTF) measurement of projection lens,so we analyze a real-time MTF measurement system based on image analysis for projection lens in this paper.Using CCD as an image receiver and based on image analysis,a method of MTF measurement is discussed.According to analyzing a single pixel image,the method can acquire tangential and sagittal MTF data at one measurement.The structure and theoretical model of the test system are expounded.The importance of system parameter calibration and how to calibrate correctly are emphatically analyzed.The factors that influence the results and how to correct the noise effect are also analyzed.Compared measurement results of a qualified projection lens and an unqualified projection lens with the designed datum,the comparison experiment show the validity of the system and the method.