拍照手机镜头MTF的测量方法

镜头调制传递函数(MTF)的测量有正投影和逆投影两种方法。拍照手机镜头由于体积小、后焦短、所配感光器的像素越来越高,正投影法测量用的CMOS/CCD受其保护玻璃厚度和自身像素的制约而有局限性;逆投影法颠倒镜头成像系统物和像的位置,克服了手机镜头后焦、像素等的限制。实验结果证明逆投影法能快速测量拍照手机镜头的MTF,方便评定镜头的品质,有较大的实用价值。

Measuring method of mobile phone lens MTF

There are obverse and adverse projection two methods for measure modulation transfer function(MTF) of lens.The volume of mobile phone lens is very small,the back focus length of lens is very short and resolution power of sensor is more and more high.The obverse projection method is limited because of protective glass and pixel of CMOS/CCD.The adverse projection measuring method reverse the position of object and image in the imaging system of lens,it overcome back focus length and resolution power limitation.The experimental result indicates that adverse projection measuring method can speedy measure MTF of mobile phone lens.It is convenience to evaluate the quality of mobile phone lens and has a good utility value.