Patent ID: 8328800

Claim:
An electrosurgical device for directing energy to a target volume of tissue, comprising: a coaxial feedline having an inner conductor, an outer conductor coaxially disposed around the inner conductor, and a dielectric material disposed therebetween; an elongated electrically-conductive member longitudinally disposed at a distal end of the inner conductor; a balun including: a dielectric layer coaxially disposed around a distal portion of the outer conductor of the feedline; and an electrically-conductive layer coaxially disposed around a proximal portion of the dielectric layer, wherein the dielectric layer extends distally beyond a distal end of the electrically-conductive layer; an electrically-conductive cylinder coaxially disposed around a distal portion of the balun; and a dielectric structure disposed substantially adjacent to a distal end of the electrically-conductive cylinder, wherein the dielectric structure longitudinally extends from the distal end of the electrically-conductive cylinder to a distal end of the electrically-conductive member.