Method for producing an electrostatic lens

摘要

An electrostatic lens produces a smooth potential distribution along the center axis and is reduced in lens size and in total shape. A metal layer 13 is deposited at a certain position on an inner surface of insulating cylinder 11, and a high-resistance layer 12 is deposited on a portion except for the metal layer 13 on the inner surface of cylinder 11. A negative potential is applied from an external power source 19 to the metal layer 13, and the high-resistance layer 12 is earthed.