| 摘要 |
<p>PURPOSE:To uniformly hold the position accuracy of a grid over the entire width of a head in the longitudinal direction, by holding a grid electrode by a rigid member. CONSTITUTION:A first grid 27 and second grid 28 are held by an insulating rigid member 29 of 10<6>OMEGA.cm or more. The grids 27, 28 are opened in a rectangular shape at the parts expect light emitting elements 15 and the sizes of the opening parts are set so as not only to make the first grid larger than the second grid but also to prevent the insulating rigid member from being exposed between the first and second grids when the grids are viewed from a cathode filament 16. The optimum thickness of the rigid member is 0.03-3.00 mm. Since grid electrodes can be held at positions uniform from a substrate over the whole of a head in the longitudinal direction, the brightness irregularity of the light emitting fluorescent body 15 is not generated.</p> |
