Electron emission element.

摘要

An electron emission element comprises a P-type semiconductor substrate (1) and electrodes (2, 3) formed on both ends of the semiconductor substrate. A voltage is applied between said electrodes. The P-type semiconductor substrate is irradiated with light to emit the electrons, generated in the P-type semiconductor substrate by photoexcitation, from an electron emitting face (4) at an end of the P-type semiconductor substrate.