@misc{oai:ir.soken.ac.jp:00001118,
 author = {Danev, Radostin Stoyanov and ダネブ, ラドスティン ストヤノフ and Danev, Radostin Stoyanov},
 month = {2016-02-17, 2016-02-17},
 note = {The possibility of implementing a Zernike phase plate in a transmission electron microscope is investigated both theoretically and experimentally. The phase-retarding plate in the form of thin film with a hole in the center is positioned in the back-focal plane of the objective lens. The experiments showed that the phase plate functions as predicted, producing a cosine-type phase contrast transfer function. Images of negatively stained horse spleen ferritin were highly improved in the contrast and the image-modulation, compared to those acquired without the phase plate. Electrostatic charging and related difficulties were encountered during the phase plate experiments.<br />The radial distribution of the beam-induced charge in thin films was investigated using the contrast transfer properties of the transmission electron microscope. The phase shift due to charging was measured as the phase difference between the contrast transfer functions of two photos taken with and without film at the back focal plane. Solving the inverse Laplace problem with this input data recovers the charge density of the measured film. The surface charge density reaches quasi-equilibrium state after the first 30 min of the electron beam pre-irradiation. An explanation of the qualitative behavior of the charge density, based on the contamination diffusion theory, is proposed.<br />The first experimental realization of the complex reconstruction scheme is presented. Two images taken with and without Zernike phase plate are used for the extraction of both the phase and the amplitude of the object wave. New “off- plane” application scheme for the phase plate was developed, to overcome various practical problems. Aberration-corrected phase images of negatively stained horse spleen ferritin and tobacco mosaic virus samples are free from image distortion and show extraordinary high contrast compared to that obtained with conventional TEM., 総研大甲第562号},
 title = {Application of Zernike Phase Plate to Transmission Electron Microscopy},
 year = {}
}