| 摘要 |
<p>The light which is emitted from the output screen of an image intensifier and passed through a subsequent output objective, is converted into an electrical signal by means of a photomultiplier tube or an image pick-up tube. The noise or modulation content of the electrical signal are measured. An optimum adjustment of the focussing position of the output objective and the magnitude of the focussing voltage applied to the imge intensifier, cause the noise or modulation content to attain an extreme value, e.g. a maximum. The focussing voltage and the focussing position of the output objective are iteratively adjusted.</p> |
