But the material of emitting cathode is mostly present with big escaping power, low reliability, low uniformity and emission capability.

目前，场发射阴极材料多种多样，但都存在逸出功大，稳定性及均匀性不理想，发射性能低等方面的问题。

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The contacting area of the electron-emitting layer and the cathode electrode is limited to the periphery except a center part on the bottom face of the hole.

因此，由于电子发射层接收来自位于其侧 面的阴极电极的电子，所以电子主要从电子发射层表面的边缘部发射， 借此提高电子聚焦性能。

youdao

The contacting area of the electron-emitting layer and the cathode electrode is limited to the periphery except a center part on the bottom face of the hole.

因此，由于电子发射层接收来自位于其侧 面的阴极电极的电子，所以电子主要从电子发射层表面的边缘部发射， 借此提高电子聚焦性能。

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