著者

Kuniaki Nagayama

出版者

THE PHYSICAL SOCIETY OF JAPAN

雑誌

Journal of the Physical Society of Japan (ISSN:00319015)

巻号頁・発行日

vol.73, no.10, pp.2725-2731, 2004-10-15 (Released:2007-07-25)

参考文献数

31

被引用文献数

5

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Conventional phase retrieval in transmission microscopy is applicable only to weak objects that perturb the incidence with a phase that is π⁄2 or smaller. We propose a novel phase retrieval technique applicable to strong objects. The innovation core is the scanning of a knife-edge, which is conventionally fixed to recover phase information. The synchronous operation between the scanning of the knife-edge and the image accumulation enables a novel spatial filter, which draws phase retardations by objects in the form of their first derivative. Combining the left- and right-scanning of the knife-edge can completely expel image components that are non-linear to the wavefront functions. Theoretical formulation of knife-edge scanning filters and corresponding numerical simulations specific to an electron microscope are proposed.