| 摘要 |
PROBLEM TO BE SOLVED: To provide a cold cathode-type electron gun with low aberration that has high brightness even in a large current.SOLUTION: A field emission-type electron gun of the present invention draws electron beams out of a cathode and converges the drawn electron beams, and includes a magnetic field lens so that the cathode is arranged in a lens magnetic field. An extraction electrode for drawing electrons out of the cathode is configured in a cylindrical shape having no diaphragm structure. According to the present invention, the electron gun having a function to converge electron beams by using a magnetic field, reducing an electrostatic lens action occurring in association with the convergence, and having less aberration and high brightness, can be provided. |
