Patent ID: 6608444
Filing Date: 2003-08-19
Classification: H01J

Abstract:
A mercury-free high-intensity discharge lamp operating apparatus comprising:a horizontally operated high-intensity discharge lamp including an arc tube in which a luminous material is enclosed and a pair of electrodes are arranged in the arc tube; a ballast including an alternating current generation means for supplying alternating current to the pair of electrodes; and a magnetic field application means for applying in substantially vertical direction a magnetic field having a component that is substantially perpendicular to a straight line connecting heads of the pair of electrodes; wherein mercury is not included as the luminous material in the arc tube; and satisfying the relationship 0BW/f)âˆ’P0d<100 wherein B(mT) is the magnetic field applied to a center between the heads of the pair of electrodes, d(mm) is a distance between the heads of the pair of electrodes, P0(MPa) is a pressure inside the arc tube during steady-state operation, W(W) is a power consumed during steady-state operation and f(Hz) is a steady-state frequency during steady-state operation.