Danev R, Nagayama K
National Institute for Physiological Sciences, Okazaki National Research Institutes, Japan.
Ultramicroscopy. 2001 Sep;88(4):243-52. doi: 10.1016/s0304-3991(01)00088-2.
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 show 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. Charging and related difficulties were encountered during the phase plate experiments. In order to make the technique user-friendly a number of improvements have to be made, and are discussed in terms of the current level of technology and instrumentation.
本文从理论和实验两方面研究了在透射电子显微镜中实现泽尼克相位板的可能性。中心带孔的薄膜形式的相位延迟板位于物镜的后焦平面。实验表明，相位板的功能符合预期，产生了余弦型相位对比度传递函数。与未使用相位板获取的图像相比，负染色马脾铁蛋白的图像在对比度和图像调制方面有了显著改善。在相位板实验过程中遇到了充电及相关问题。为了使该技术便于用户使用，必须进行一些改进，并根据当前的技术和仪器水平进行了讨论。
