对系统的关键性部件如照明系统、光栅、物镜和电子目镜的选用以及它们对系统性能的影响进行了分析。

The particular functions and the impact to the systemic performance of the critical elements such as lighting system, grating, field lens and electronic ocular are analyzed.

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用假设弱透镜焦距表达式是一个幂级数中的第一项的方法，可以导出相当准确且便于实用的电磁电子透镜物镜焦距公式。

By assuming the weak lens focal length expression to be the first term in a power series a simple and accurate formula can be derived for the objective focal length of a magnetic electron lens.

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为了在有限口径下获得更大的观察范围，医用电子内窥镜广泛采用广角物镜，图象存在较为严重的畸变。

Due to the restriction of the coelom of human organs, wide angle lenses are widely used in the medical electronic endoscope whose images are distorted badly.

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