THE FREQUENCY RESPONSE FUNCTION IN A COHERENT OPTICAL SYSTEM AND ITS FREQUENCY SELECTION CHARACTERISTICS IN TRANSMITTING OPTICAL INFORMATION
相干情形下的反应函数以及光学信息的选择传送

This paper gives an expression of the optical frequency response function suitable for both the incoherent and the coherent optical system. Its physical aspect reveals that the frequency response function plays the role of an information selector.The Becke phenomenon for detesting small refractive index difference between object and its surrounding medium by observing the apparent movement of the diffractional border line (Becke line) on defocusing the optical system has been explained.