multiuse polepiece

The "multiuse polepiece" allows the specimen holder to be tilted to more than ±35°. This polepiece makes it possible to attain a Cs of 1.0 mm, a Cc of 1.4 mm and a spatial resolution for TEM image of 0.23 nm at an accelerating voltage of 200 kV. For analytical case, the objective aperture is inserted below the lower pole of the polepiece to avoid unnecessary X-rays from the aperture. This aperture setting causes a problem that the diffraction pattern is not formed on the aperture plane, which leads to a difficulty in acquiring the dark field image from one diffraction spot and the bright field image without the influence of surrounding diffraction spots. It is noted that there is option to insert a special aperture at the polepiece gap to obtain correct bright- and dark-field images.

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