General color rendering index as function of current change ratio in wall-stabilized arc of water-cooled vortex type with small caliber

Improvement of color rendering spectrum is required because the high-intensity discharge (HID) lamp is used as a large-scale illumination for emergency. The HID lamp is high lamp efficiency and the low color rendering spectrum because it uses the combination of line spectrum. The broad spectral distribution is needed for improvement of the color rendering spectrum. The energy balance to achieve both the color rendering spectrum and lamp efficiency is important. The energy balance is changed by controlling the temperature distribution. It is necessary to control the temperature distribution with controlling the current and radius. The wall-stabilized arc of water-cooled vortex type with small caliber was developed for improvement of the color rendering and lamp efficiency. In addition, the pulsed arc changes the temperature distribution because the pulsed current changes with time. The temperature distribution is changed by controlling the current change ratio. In this paper, the general color rendering index as function of the current change ratio in the wall-stabilized arc of water-cooled vortex type with small caliber was measured. As a result, the general color rendering index had the peak with increasing the current change ratio. Therefore, the temperature distribution plays important role for the color rendering spectrum.