Abstract
High color rendering compact HID lamps are being used for indoor lighting.
This is because HID lamps have higher efficiency and longer life than those of incandescent and tungsten halogen lamps. Also HID lamps are more compact and have higher lumen output when compared to fluorescent lamps.
In the future lamp safety will be a important factor, particular being paid to the following areas--
* Shattering. *Ultra violet radiation. *High starting voltage.
It is also expected that higher color rendering is required especially in the red (R9).
The double ended metalhalide lamp is one type of those HID lamps, with acolor temperature of 3000K and 4300K. However the color rendering index (Ra) of both of these lamps was lower than 90.
Dy-T1-I type lamp has excellent color rendering with Ra 90 or more, but the color temperature is high at approximately 6000K.
We tried to lower the color temperature without reducing the Ra, which is particularly important for interior lighting, so it was considered that Ra of 90 or more and R9 of 50 or more was essential.
We developed the 150W Dy-Tl-I type compact metalhalide lamp which has the desirable color temperature around 4300K and excellent color rendering, Ra 90 and R9 of 84. New lamp also designed more safty, about shattering, UV radiation and high starting voltage.
