DISPLAY TUBE USING FILAMENT

摘要

PURPOSE: To avoid heating of the coil part in the display tube using the cathode filament comprising the straight line part and coil part. CONSTITUTION: A filament support 161 is fixed on the glass substrate 11 by electrically being insulated and the top end of the coil part 152 of the filament is welded to the support 161. The top end of the straight line part 151 of the filament is welded to the support (not shown). The coil part 152 gives a prescribed tension to the filament. A contact metal member 141 is fixed on the feeding wiring 131 formed on the substrate 11, and the straight line part 151 of the filament is contacted on the top end of the metal member 141. The contact metal member 141 and the straight line part 151 are electrically connected. The straight line part 151 is supplied with electric current, but the coil part 152 is not supplied with current and so is not heated.