摘要:
A simple and effective technique for reducing an external magnet flux emitted from a driven inductor (19) surrounded by an ionizable gaseous medium (15). This technique includes surrounding the inductor (19) with at least one shielding conductive loop (23), terminating the shielding loop in a capacitive termination (24) to resonate, and maintaining a resonant frequency of the capacitive termination (24) in series with an inductance of the shielding loop (23) below the predetermined driving frequency of the inductor (19).
摘要:
An electric lamp assembly includes an electrodeless lamp having an electrodeless lamp envelope enclosing a fill material for supporting a low pressure discharge, a driving inductor including a magnetic core disposed in proximity to the lamp envelope and an input winding disposed on the magnetic core, a compensation loop disposed in proximity to the lamp envelope, a radio frequency power source and a compensation loop network. The compensation loop network has an input coupled to the radio frequency power source and outputs coupled to the input winding and to the compensation loop. The radio frequency power source and the compensation loop network supply radio frequency energy to the electrodeless lamp to produce a discharge in the lamp envelope and supply radio frequency energy to the compensation loop to generate a magnetic field that substantially counteracts a magnetic field produced by the discharge. In one embodiment, the lamp envelope is a closed-loop, tubular lamp envelope, and the magnetic core is disposed around the lamp envelope. In another embodiment, the lamp envelope includes a reentrant cavity, and the magnetic core is disposed in the reentrant cavity.