| 摘要 |
PURPOSE:To obtain an image tube, which has an electrode group, which is constituted so that the unnecessary part of an input picture is removed, by making the input-picture-side part of the electrode group, which forms an electron lens and to which a non-circular input picture is fed, unsymmetrical with respect to a point, and making the output-picture-side part of the electrode group symmetrical with respect to a point. CONSTITUTION:When the distribution of electric potentials corresponding to the section 31 of an image tube having a rectangular input surface is examined, equipotential lines including 0V, the electric potential of a cathode K, and 5V and spaced at 10V from after 10V are obtained. For instance, when a belt-like metallic film is baked on a ceramic surface and an electrode group with such equipotential lines as above is provided at the section 31, inside an electron lens which is sufficiently apart from the pitches of the equipotential lines, the electric-potential distribution becomes as if it is formed with an electrode group which is symmetrical with respect to a point. Thus an electrode group for an image tube which has a rectangular input surface is constituted. Such an image tube, when installed in a system, can widely increase the performance of the system. |
