| 摘要 |
PURPOSE:To restrain a cataphoretic phenomenon from occurring, by installing the coldest point spot in the vicinity of either of electrodes installed in both ends of a light emitting tube, while setting the electrode at the side proximate to the coldest point spot down to the anode, and lighting a lamp with a DC chopper circuit. CONSTITUTION:Either of fine tubes 13 and 14 installed in both ends of a light emitting tube 1', for example, the fine tube 13 is made longer than the tube 14, while the coldest point spot 15 is installed in the vicinity of an electrode 10. And, when this light emitting tube 1' is lighted with a DC current by a DC chopper circuit, a power transistor 19 is driven by a control circuit consisting of a multivibrator circuit or the like, repeating its chopping motion, whereby a continuous discharge state by a DC current is kep up at the light emitting tube 1' owing to operations of a choke coil 21, a condenser 22 and a diode 23. In this case, when the electrode 10 at the side proximate to the coldest point spot 15 is operated, a cataphoretic phenomenon is remarkably restrained, and in a normal temperature state, almost uniform light emission is securable over the whole region of the light emitting tube 1'. |
