部分的コヒーレント照明下におけるDefocus光学系の結像特性

抄録

Image focussing characteristics of the defocused optical system under different illumination modes are investigated by means of the transmission cross coefficients T(f, 0), T(f, -f) and the optical transfer function under linear approximation in a partially coherent optical system. Images of Siemens star for corresponding optical condition are simulated and assessed from the viewpoint of the system performance.
It is shown that special features of imaging characteristics of the defocused optical system are encountered in coherent, near-coherent and annular illumination modes. The corresponding images for a largely defocused optical system differ remarkably from the original object. It is also clarified that contrast reversal in the image occurs more easily under the illumination closer to a coherent rather than incoherent one. Furthermore, other informations on image ap pearance in partially coherent, defocused optical system are presented.
Finally, theoretical considerations which have been verified experimentally.