摘要 |
An ion energy analyzer (100) having a micro-channel plate (104) where the geometric filtering characteristics of the micro-channel plate (104) are electrically controlled. The ion energy analyzer contains a metallic collector (116), a control grid (108) and a micro-channel plate (104), all formed into a cylindrical stack where the collector (116), control grid (108) and micro-channel plate (104) are separated by ceramic insulating washers. A control element is formed within each aperture (124) of the micro-channel plate (104) for controlling a critical angle of each aperture (124). A voltage is applied to the control element such that an electric field is generated within each micro-channel (124). By varying the magnitude of the electric field, the critical angle of the micro-channel plate (104) can be electrically controlled, and as such, certain ion trajectories can be selected for entry into the ion energy analyzer (100). <IMAGE> |