| 摘要 |
PURPOSE:To eliminate variations of the beam permeability in the alignment direction of the scanning beam and to reduce the mesh beat by forming aperture sections of a mesh electrode into hexagons with opposing sides in the scanning beam direction. CONSTITUTION:Mesh electrodes arranged in parallel face to face at a distance of several mm. on an electron beam scanning screen which is a photoelectric conversion screen of a camera tube are formed with a metal thin film net 1 and mesh aperture sections 2, which are formed into hexagons with opposing sides in the scanning direction R3. Accordingly, the width of the intersection 1a of the metal thin net 1 innthe scanning direction R3 becomes wide, and a triangle 1b is formed at one diagonal section of the aperture section 2, therefore proper selection of the width a so as to lower the beam permeability can be reduce the spatial variations of the passing electron beam quantity, thus reducing the mesh beat remarkably. |
