| 摘要 |
PROBLEM TO BE SOLVED: To provide a fluorescent discharge tube capable of retaining a non-defective level by improving dark starting characteristics, and of improving quality and yield. SOLUTION: This is provided with an ultraviolet ray transmitting glass tube in which a phosphor film is formed on the inner face, and in which a noble gas and mercury, or the noble gas are sealed inside, a pair of cup electrodes CE which are sealed and arranged opposite to both end parts of this glass tube, and a pair of lead wires for power feeding in which one end is connected to these cup electrodes CE and the other end is airtightly sealed and drawn outside the glass tube. By integrally forming a recess groove DEN which is recessed in the electrode axial direction along the electrode axial direction on the outer face of the pair of cup electrodes CE, an electric charge becomes easy to be collected at starting, and lighting delay is efficiently eliminated, since sputtering from the recessed groove DEN of the cup electrodes CE becomes easier to be film-formed as a sputtering thin film on the inner wall faces of the opposite glass tube in an aging process during the manufacturing process. COPYRIGHT: (C)2007,JPO&INPIT |
