Why isn't the light emitted by a high-pressure sodium lamp incandescent?
In other words, the low color temperature color index is not necessarily low; the color temperature high color index is not necessarily high!P.S. for personal opinion, if there is inappropriate, please exhibitions!
Incandescent lamp spectrum continuous, similar to the heat radiation of the sun, the color index is 100, but the color temperature is low, yellow.
This problem is good, in fact there are two concepts in lighting: color temperature and color rendering index; color temperature of high pressure sodium lamp is about 2000K, the spectral components are yellow, green and blue because of lack of spectrum, lead to the color index is only about 25.
