Radioactive starting aids for electrodeless light sources

An electromagnetic discharge apparatus comprising:

• electrodeless lamp means having a lamp envelope made of a light transmitting substance, said envelope having an inner surface and enclosing a fill material which emits light during electromagnetic discharge;
• means coupled to said electrodeless lamp means for excitation of said fill material and adapted for delivering high frequency power to said lamp means for sustaining said electromagnetic discharge;
• and
• a radioactive material associated with said discharge apparatus and selected from the group consisting of iodine 129, nickel 63, cesium 137, antimony 125, holmium 166, thulium 171, thallium 204, thorium 228, cadmium 113, and americium 241, said radioactive material having a half-life sufficient to produce radioactive emissions during the useful life of said discharge apparatus and producing radioactive emissions with sufficient energy to reach the inner surface of said lamp envelope, said radioactive emissions being operative to predispose on the inner surface of said lamp envelope loosely bound charges which thereafter assist in initiating discharge.

An electromagnetic discharge apparatus comprising:

• electrodeless lamp means having a lamp envelope made of a light transmitting substance, said envelope having an inner surface and enclosing a fill material which emits light during electromagnetic discharge;
• means coupled to said electrodeless lamp means for excitation of said fill material and adapted for delivering high frequency power to said lamp means for sustaining said electromagnetic discharge;
• and
• a radioactive material outside said envelope and associated with said excitation means, said radioactive material having a half-life sufficient to produce radioactive emissions during the useful life of said discharge apparatus and producing radioactive emissions with sufficient energy to reach the inner surface of said lamp envelope, said radioactive emissions including gamma rays and being operative to predispose on the inner surface of said lamp envelope loosely bound charges which thereafter assist in initiating discharge.