Image display tube having a channel plate electron multiplier

摘要

The image contrast in an image display tube having a channel plate electron multiplier (2) is improved by preventing secondary electrons emitted from the face of an input dynode (26) from straying to channels located at a relatively large distance from their origin. This is done by disposing a grid (24) at a short distance from the input dynode (26). If the grid (24) is held at a positive voltage relative to the input dynode (26), stray secondary electrons will be attracted toward the grid (24). Alternatively, if the grid (24) is held at a negative voltage relative to that of the input dynode (26), the secondary electrons will be induced to enter channels close to their origin.