| 摘要 |
PURPOSE:To produce excellent illumination presentation by multiple different light colors with few facilities by storing multiple high-pressure discharge lamp light emitting tubes having different light colors in one outer bulb, and selectively lighting the light emitting tubes as required. CONSTITUTION:A high-pressure mercury lamp light emitting tube 1 made of quartz glass and a high-pressure sodium lamp light emitting tube 4 made of translucent alumina ceramic are arranged in an outer bulb 7 made of hard glass, lead wires 8a, 9a of a main electrode 2b of the light emitting tube 1 and a main electrode 5a of the light emitting tube 4 are electrically connected, and they are connected to an AC power source 11 via the external ballast winding 10 of the outer bulb 7. The lead wire 8b of the other main electrode 2a of the light emitting tube 1 and the lead wire 9b of the other main electrode 5b of the light emitting tube 4 are connected to the AC power source 11 via the contacts A, A' and B, B' of a selector switch 12 directly (for 8b) and through an auxiliary winding 13 (for 9b) respectively. When the contacts of the selector switch 12 are connected to the A, A' side or the B, B' side, the white light by the high-pressure mercury lamp light emitting tube 1 or the orange light by the high-pressure sodium lamp light emitting tube 4 are selectively illuminated automatically. |
