Light generation by an electrodeless fluorescent lamp

An electrodeless discharge lamp comprising:

• a sealed envelope;
• an ionizable medium within said envelope including at least one particular ionizable gas at a given pressure capable emitting radiant energy when subjected to a radio frequency field;
• and
• means including an induction coil wrapped around a nonmagnetic core positioned in close physical proximity to said medium in said envelope for coupling to said medium an electric field having a magnitude sufficient to initiate ionization of said medium and for simultaneously coupling to said medium in said envelope a radio frequency magnetic induction field for maintaining said ionization, the peak magnitude and frequency of said magnetic induction field being selected to optimize the efficiency of conversion of radio frequency energy coupled to said medium to emitted radiant energy.

A high frequency electrodeless fluorescent lamp comprising:

• a sealed envelope;
• a charge in said envelope comprising an inert starting gas and mercury vapor;
• a layer of fluorescent light emitting phosphor disposed on the inner surface of said envelope, said phosphor being capable of emitting white light within the visible spectrum upon absorption of ultraviolet radiation from said mercury vapor when ionized;
• an induction coil wrapped around a nonmagnetic core positioned so a substantial portion of its magnetic induction field passes through said charge in said envelope;
• means for generating electrical energy at a radio frequency above three megahertz;
• and
• means for coupling said electrical energy to said induction coil to produce thereacross an electric field that initiates ionization of said charge in said envelope to emit ultraviolet radiation and simultaneously produces a magnetic induction field for maintaining said ionization.

A high frequency electrodeless fluorescent lamp comprising:

• a sealed envelope;
• an ionizable medium within said envelope;
• an oscillator for generating high frequency electrical energy, said oscillator having a resonant circuit including a capacitor and an induction coil connected in series;
• and
• means for positioning said induction coil in close proximity to said medium in said envelope so a substantial portion of its magnetic induction field and electric field passes through said medium;
• the Q of said capacitor and induction coil being sufficiently large that the electric field across said induction coil initiates break down of said ionizable medium to form radiation emitting ionization and
• said magnetic induction field being sufficiently large to maintain the radiation emitting ionization of said medium.