Application of vane-type resonator to microwave powered electrodeless HID lamp

Summary form only given. A vane-type resonator is generally known as an anode of a magnetron, which controls the oscillation frequency of the magnetron. The vane-type resonator, made of aluminum and so on, forms a structure in which vanes protrude toward the center of a cylinder. A microwave resonant electric field is generated inside of a space formed by the vane protuberant portions, where ther is an electrodeless high intensity discharge (HID) lamp. The inner diameter of the resonant space can be 10 mm and below at 2.45 GHz. Compared with the cavity resonator, the resonant electric field generated at the center of vane-type resonator can be concentrated in a very small space. Therefore, a much smaller plasma arc can be maintained by using the vane-type resonator. We used a 3D finite element method simulation for the design of a vane-type resonator with a parabolic reflector to obtain the desired resonant frequency. According to the results of the simulation, the size of a 4-vanes resonator with a parabolic reflector were decided, and the resonator made of aluminum and copper was prepared. An electrodeless lamp with InBr and Ar gas enclosed in a spherical quartz glass tube having an inner diameter of about 4 mm was also prepared, and was set at center portion of the resonator. The total luminous flux was about 2150 lm at a microwave input of 27 W. The CRI and Tc for this lamp were 93 and 10200 K, respectively.