Helical antenna, method for manufacturing the helical antenna, and method for adjusting resonance frequency

摘要

A plurality of copper wires are disposed between coaxially arranged an inner cylindrical member and an outer cylindrical member, with one end of each copper wire being fixed at a predetermined position. The remaining portion of each copper wire is spirally bent so as to wind itself around the inner cylindrical member, with the center axes of both the inner cylindrical member and the outer cylindrical member serving as a winding center. Then, an amount of insulative resin is poured into an annular space formed between the inner cylindrical member and the outer cylindrical member. In this way, the spirally deformed copper wires are sealed within the wall portion of a hollow cylindrical insulative resin member.