Abstract: A discharge lamp includes a body portion having inner and outer body walls and first and second ends. The inner body wall defines at least part of a cavity located between the first and second ends. First and second end parts have inner end-part and outer end-part walls and a hole extending between the inner end-part wall and the outer end-part wall. The first and second end parts are each located, at least in part, within the cavity and separate from each other so as to maintain a gas under pressure. First and second electrodes are included in the cavity. An antenna has first and second antenna ends and is formed on the outer body wall of the body portion and the outer end-part wall of at least one of the first and second end parts. The antenna is not directly connected to the first and second electrodes.

Abstract: A driver apparatus (100) for driving a gas discharge lamp (L) comprises a commutator circuit (5) having a bridge topology with four switches (T1-T4) controlled by a controller (6), with an inductor (L2) arranged in series with the lamp and a capacitor (C3) arranged in parallel with the lamp, the inductor (L2) and the capacitor (C3) having a parallel resonance frequency fR. In a steady-state mode, the controller drives the four switches (T1-T4) at a relatively low commutation frequency of the order of 100 Hz. For igniting the lamp when it is still hot, the controller drives the four switches (T1-T4) at a first ignition frequency fP1=fR/n1, n1 being an odd integer. For igniting the lamp when it is cold, the controller drives the four switches (T1-T4) at a second ignition frequency fP2=fR/n2, n2 being an odd integer larger than n1.

Abstract: A discharge lamp includes a body portion having inner and outer body walls and first and second ends. The inner body wall defines at least part of a cavity located between the first and second ends. First and second end parts have inner end-part and outer end-part walls and a hole extending between the inner end-part wall and the outer end-part wall. The first and second end parts are each located, at least in part, within the cavity and separate from each other so as to maintain a gas under pressure. First and second electrodes are included in the cavity. An antenna has first and second antenna ends and is formed on the outer body wall of the body portion and the outer end-part wall of at least one of the first and second end parts. The antenna is not directly connected to the first and second electrodes.

Abstract: A driver apparatus (100) for driving a gas discharge lamp (L) comprises a commutator circuit (5) having a bridge topology with four switches (T1-T4) controlled by a controller (6), with an inductor (L2) arranged in series with the lamp and a capacitor (C3) arranged in parallel with the lamp, the inductor (L2) and the capacitor (C3) having a parallel resonance frequency fR. In a steady-state mode, the controller drives the four switches (T1-T4) at a relatively low commutation frequency of the order of 100 Hz. For igniting the lamp when it is still hot, the controller drives the four switches (T1-T4) at a first ignition frequency fP1=fR/n1, n1 being an odd integer. For igniting the lamp when it is cold, the controller drives the four switches (T1-T4) at a second ignition frequency fP2=fR/n2, n2 being an odd integer larger than n1.