Ceramics in Optics
Over the last number of years, yttria-alumina garnet (YAG:Ce) has been used as the most efficient yellow phosphor for the white LEDs because of its high luminescence efficiency and good color rendering index. However, the content of red color in YAG:Ce phosphor is insufficient to produce desirable color balance for a warm-white color. So far, two methods have been used to produce warm white lights. One is to combine an UV chip with red, green and blue phosphors and another one is to compensate the red deficiency of YAG:Ce-based LED with a separate red light.
Functional Materials Manufacturing Inc. has developed a novel composition and structure YAG:Ce phosphor capable of emitting increased level of red color. This summary describes the properties of a new generation of YAG:Ce phosphor which can be fabricated in a powder form and in a solid state forms. The advantages of this new phosphor are as follows:
The material can be produced in powder in various forms:
-Thin and thick films
Alumina (Al2O3)-Based Red Phosphor
FMM has developed process for the fabrication of high intensity alumina-based phosphor with deep red color emission suiabl for use as a single source of red color.