| 摘要 |
In order to increase the depth of field of an optical system, there is provision to add a phase object, interposed between an object (O) to be imaged and an image plane (8) of the optical system. The phase object is interposed although a chromatic aberration of the system is not yet corrected. After interposition, the measured optical signal is corrected complementarily so as to eliminate the chromatic aberrations therefrom. It is shown that if a parameter of the expansion of the expression, a function of pupil dependency, that the difference in path length of the optical system possesses a significant value of higher order than that of the defocus, then an increase in the depth of field is obtained.
|
