Patent ID: 8072155

Claim:
An electrodeless discharge lamp device having a bulb filled with discharge gas, said electrodeless discharge lamp device comprising: an induction coil being disposed adjacent to said bulb and being configured to generate a high-frequency electromagnetic field for exciting said discharge gas; a pair of approximately semi-cylindrical cores being arranged to give an overall circumference around which said induction coil is wound, said semi-cylindrical cores being spaced to form a space therebetween; and a thermal conductor being formed into an approximately cylindrical shape and inserted into said space so as to be thermally coupled with said cores for radiating heat generated at said cores, wherein said core having its inside face at least a center portion of which is spaced radially from said thermal conductor by a predetermined distance, wherein a spacer made of an elastic material and shaped into a thin plate is interposed between each of said cores and said thermal conductor to occupy said distance, wherein said spacer comprises a tape of a glass knitted fabric with an adhesive layer in at least one surface thereof.