A glass tube of aluminosilicate glass, with high dielectric constant K∼6.0 and low dielectric loss tan δ∼8.0×10−4, was investigated for the external electrode fluorescent lamps (EEFLs) of a dielectric barrier discharge. Compared with conventional EEFLs made out of borosilicate glass tubes with K∼(4.9−5.3) and tan δ∼(2.3−2.4)×10−3, the efficiency of the aluminosilicate EEFL increases by 15%−25% even at high luminance above 20 000 cd/m2 and the pinhole stability of the aluminosilicate EEFL also improves remarkably. In a soda-lime glass EEFL with a high dielectric loss tan δ∼7.0×10−3, the luminance and pinhole stability deteriorate even with a high dielectric constant K∼7.2 at room temperature, because the value of tan δ escalates as the temperature on the external electrode increases due to the dielectric heat dissipation.

A center balancing operation is proposed for a large area LCD backlight with the multi‐lamps driven by a single inverter. This new method minimizes the power leakage due to the parasitic capacitance of the backlight metal housing.

Application of power higher than the optimum operation value to an external electrode fluorescent lamp (EEFL) leads to the formation of pinholes, which subsequently leads to lamp failure. Small holes, called pinholes, are formed through the external electrode and the glass tube when a high voltage with a high power is applied. The phenomenon of pinhole formation has been investigated, including the conditions under which they occur and the characteristics such as size and location on the electrode. Pinhole formation has been analysed and shown to be the insulation layer breakdown of glass in the dielectric barrier discharge of capacitively coupled EEFLs.

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At the pressure range of 30~200 Torr in EEFLs, the lifetimes will be discussed to be about 60,000 hours in the long run operation of 11,000 hours. In the test of lamp failure, pinhole formation has been shown to be the insulation layer breakdown of glass in the dielectric barrier discharge of capacitive coupled EEFLs.