| 摘要 |
There is disclosed an electron microscope that achieves low-magnification imaging while the objective lens is kept at high excitation in the same way as during high-magnification imaging. An objective minilens located immediately behind the objective lens demagnifies a specimen image magnified by the objective lens. Consequently, a sharply focused electron beam enters the first intermediate lens. This greatly reduces the effects of off-axis aberrations in the intermediate lenses. The first, second, and third intermediate lenses create a crossover image and a microscope image in the entrance window plane and entrance image plane, respectively, of an energy filter. The energy filter focuses the microscope image and crossover image onto the exit image plane and exit window plane, respectively. The output image from the filter is projected onto the final image plane by first and second projector lenses.
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