title: Contrast enhancement in the phase plate transmission electron microscopy using an objective lens with a long focal length.
abstract: A new optical condition using an objective lens (OL) of a long focal length (objective mini lens: OM) was tested to enhance image contrast in phase plate transmission electron microscopy (P-TEM). A phase plate was set on the selected area aperture plane where diffraction patterns were formed under the optical condition using the OM. A phase shift by the phase plate was added to the electron waves to visualize phase objects. The application of the OM to the P-TEM should provide higher phase contrast than that obtained by the OL for the phase objects. One of the reasons for the contrast enhancement is that high-angle scattering electron waves which would give the background intensity were not used for image formation due to the large spherical aberration. Another reason is that the cut-on frequency above which the phase shift was added by the phase plate could be smaller using the OL with a long focal length. Experimental results and model calculations showed the contrast enhancement of the biological specimens using the OM.
authors: Department of Applied Physics, Tokyo University of Agriculture and Technology, 2-24-16 Naka-cho, Koganei, Tokyo, Japan. hminoda@cc.tuat.ac.jp
authors: Hiroki
authors: H
authors: Minoda
authors: Tatsuhiro
authors: T
authors: Okabe
authors: Hirofumi
authors: H
authors: Iijima
mesh_terms: D000255:Adenosine Triphosphate / Q000494:pharmacology; D000818:Animals; D017979:Gold Colloid; D066298:In Vitro Techniques; D007909:Lenses; D046529:Microscopy, Electron, Transmission / Q000295:instrumentation*; D008858:Microscopy, Phase-Contrast / Q000295:instrumentation*; D008962:Models, Theoretical; D009218:Myosins / Q000187:drug effects / Q000648:ultrastructure; D055620:Optical Phenomena
chemical_list: D017979:Gold Colloid; D000255:Adenosine Triphosphate; D009218:Myosins