A battery-powered mobile scanning electron microscope which can be used even in outdoors has been developed for the purpose of showing the mystery of nature and wonder of technology to pupils/students of elementary schools, junior and senior high schools, and so on. We call this compact and easy-operation microscope the MUST-SEM (mobile-use see-through scanning electron microscope). In order to observe non-conductive samples, we employed the ionic liquid coating method. Sample preparation using this method can be carried out easily and rapidly. Observation results of microfossils of Jurassic radiolarian, intertwined genomic DNA fibers extracted from plants, and etc. are reported.

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As the initial step to realize a reliable measurement of the secondary electron yield of insulating materials using charge amplification method proposed by K. Goto, a pair of the charge amplifiers to measure a small amount of the electron charge of less than ∼1 pC have been developed. These amplifiers showed linear input⁄output characteristics within the range of the input charge of ∼0.1 to ∼6 pC. The secondary electron yield δ(Ep) of soot was measured by employing these charge amplifiers, and compared with that measured by the conventional current-mode method. The result showed that the charge amplification method enables the secondary electron yield to be measured using the primary electron charge of only ∼1 pC.

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When total reflection occurs for fast positrons at crystal surfaces, the positron beam penetrates less than 0.1nm into the crystal. Therefore, using total reflection positron diffraction we can measure surface structures and properties of the topmost crystal surfaces without bulk effects. Using this method, surface structures, adsorbed structures and surface vibration amplitudes are found for crystal surfaces. The fundamental properties of fast positron beams are described in this lecture.

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