Phosphor and Color
How Have Colors of CFLs Changed Through the Years?
Fluorescent lights have changed in many ways over the years. When it comes to color, Ed Hammer explains that there are two aspects to consider:
1. Color CRI (Color Rendition Index)
2. Efficiency
Color is based on CRI or the Color Rendition Index. An incandescent lamp has a CRI of 100. Essentially this means that it reflects every color equally, hence you see white because no colors are absorbed.
In order to create a more efficient and better maintaining bulb the Triphosphor system was introduced. It uses a refractory (aluminum) oxide host, which generates more efficient phosphor with better maintenance (compared to the traditional halo phosphate). The Triphosphor system uses 3 rare Earth phosphors. These have a more stable host structure but also are more costly, which is why they were not initially used. This system helps the bulbs to receive better lumens per watt and better maintenance over the life of the bulb.
