利用激光散斑测量CCD的调制传递函数(MTF)

本文分析了抽样成像系统的OTF,并讨论了与透镜OTF的非相干耦合问题,同时提出了一种新的测量CCD的MTF的方法。这种方法利用激光产生的散斑,在CCD的接收面上产生一个已知能谱分布的入射光强函数,对CCD信号进行A/D变换,作快速傅里叶变换(FFT),即可得到输出谱,从而求得MTF。该方法可直接对器件进行测试,不需要精密的准直设备和高质量的成像透镜,也不必对CCD的输出加放大电路,简便易行,能够满足对CCD性能进行快速检测的要求。本文测定了东芝TCD102C-1型CCD的MTF曲线。

Using Laser Speckle to Measure Modulation Transfer Function (MTF) of CCD

This paper analyses the concept of OTF in sampled imaging system, discusses the problem incoherently coupled with OTF of lens and describes a new method for measuring MTF of CCD. The main idea of this method is to use laser speckle to produce an input light intensity distribution whose power spectrum has been known in receiving plane of CCD, conduct A/D conversion to the output signal of CCD and then do FFT. to obstain output spectrum. This method can directly test devices without optical or mechanical components of high quality, precision alignment and CCD output amplifier. It is very easy, but useful in the automatic fast test of CCD performance. The MTF of Toshiba TCD102C-1 model CCD has been measured.