Patent ID: 6124679
Filing Date: 2000-09-26
Classification: H01J

Abstract:
A lamp comprising:a light bulb having an envelope for containing a substance which when excited causes the light bulb to emit light, the envelope having a cavity defined by an inward extension of the envelope, the envelope having a protuberance located at least partially within the cavity; andan induction coil for producing a variable electric field to excite the substance inside the light bulb, wherein the induction coil is located in the cavity and at least a portion of the induction coil surrounds the protuberance,wherein the light bulb has a first portion and a second portion, wherein any cross section, perpendicular to the protuberance, of the first portion has a larger area than any cross section, perpendicular to the protuberance, of the second portion, andwherein substantially all of the induction coil is adjacent to the first portion but not the second portion.