This paper reviews the basics of electron holography as an introduction of the holography part of this special issue in Microscopy. We discuss the general principle of holography and interferometry regarding measurements and analyses of phase distributions, first using the optical holography. Next, we discuss physical phenomena peculiar to electron waves that cannot be realized by light waves and principles of electromagnetic field detection and observation methods. Furthermore, we discuss the interference optical systems of the electron waves and their features, and methods of reconstruction of the phase information from electron holograms, which are essential for realization of practical electron holography. We note that following this review application of electron holography will be discussed in detail in the papers of this special issue.

中文翻译：

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电子全息术中的干涉和干涉测量

本文回顾了电子全息的基础知识，以介绍本期《显微镜》专刊的全息部分。我们首先使用光学全息术讨论关于相位分布测量和分析的全息和干涉测量的一般原理。接下来，我们将讨论光波无法实现的电子波特有的物理现象以及电磁场检测和观察方法的原理。此外，我们还讨论了电子波的干涉光学系统及其特征，以及从电子全息图重建相位信息的方法，这对于实现实际电子全息术至关重要。我们注意到，在本次特刊的论文中，将详细讨论电子全息术的这篇综述应用。