Abstract
High-frequency electric-field-coupled discharge lamps for LCD backlightings are expected to have high efficacy and long life. Since the lamps use external electrodes, the tube lengths can be extended arbitrary to cope with large LCD areas. In this paper the drive frequency was raised from 5 MHz of the previous report to 13.56 MHz, which resulted in reduced drive voltage, lower electrode temperature, and weaker Ne visible emission. These evidences show that efficacy was indeed improved. Average luminance of a 390 mm-long lamp with a diffuser plate was 2750 cd/m^2. Luminance uniformity of 74.8 % was attained by providing six sets of external electrodes.
