Intematix awarded silicate phosphor patent

March 17, 2008
A new patent covers a range of yellow-green silicate phosphors with emission in the 500-575 nm range.
Intematix Corp. a supplier of patent-backed phosphor products for solid-state lighting applications, has added US patent number 7,311,858 entitled "Silicate-based yellow-green phosphors" to its growing intellectual property portfolio.

Yellow-green phosphors are typically combined with a blue LED emitter to produce energy efficient solid-state white lighting in a growing variety of applications.

“This silicate-based approach to phosphor development provides a fundamental material advancement which has allowed Intematix’ phosphor products to leapfrog past conventional YAG solutions in white light efficiency,” said Intematix co-founder and Display & Lighting Business Unit General Manger, Yi-Qun Li, co-inventor of the patented phosphor.

Combining a blue LED with yellow phosphor is the most cost-effective method of producing white light from a single LED package. The phosphor formulations covered by Intematix ’858 patent can be tuned by varying a combination of divalent metals and halogen dopants. This can maximize the output for specific emitters and packaging materials.

The result is a series of yellow-green phosphors that cover an emission spectrum from 500nm to 575nm. The patent also covers yellow-green phosphors that can be used - in combination with specific orange or red phosphors - to achieve high color rendering and high NTSC values.

In all cases, says Intematix, the phosphor compositions boast increased stability and efficiency at the higher temperatures experienced with more powerful LEDs.

Li added, “As LED-based technologies move from specialty applications to wider adoption in general purpose lighting the pace of innovation will continue to increase. The availability of patent-backed phosphors to the marketplace, without the pre-condition of a technology license or the requirement to purchase a specific manufacturer’s LED chip, will be an important part of this market’s success.”