Intematix, a provider of phosphors to the LED (light-emitting diode) lighting and display industries, has announced that it has received patents for new technology designed to boost the color rendering index (CRI (News - Alert)) of solid state lighting (SSL) products.
Bulbs and displays with a high CRI vividly reproduce natural, lifelike hues—however, to date, most incandescent and LED light bulbs have not achieved a CRI above 90. Now, Intematix claims to have demonstrated CRIs as high as 98.
Patent numbers 8,529,791 and 8,475,683 regarding green- and yellow-emitting, garnet-based phosphors were issued to Fremont, CA (News - Alert)-based Intematix on Sept. 10 and July 2 of this year, respectively, by the United States Patent and Trademark Office. The patents cover intellectual property that could be applied in both general lighting applications and in display backlighting.
Specifically the green aluminate (GAL) phosphors can be combined with red phosphors to produce lighting with a high CRI ranking. "By using our GAL phosphors, LED solutions may be designed for efficient performance at CRIs greater than 90," explained Yi-Qun Li, chief technology officer at Intematix.
Photo courtesy Intematix
High CRI is especially important in applications such as retail and hospitality and in some cases is mandated by market-incentive programs. Intematix's Li added, "This technology is instrumental to meeting new standards like California's Quality LED Lamp Specification."
That specification is a voluntary lighting quality standard for LED replacement lamps that requires them to meet certain performance criteria in order to qualify for incentive programs and rebates. These criteria include the color of a lamp’s light, its consistency over time, and its accuracy in rendering colors. The specification was developed in collaboration with the California Public Utilities Commission (CPUC). , Durham, NC-based Cree (News - Alert) Lighting recently introduced a 93-CRI retrofit lamp, specifically referencing the new California standard.
The company notes that GAL phosphors also provide up to 95 percent lumen maintenance at 200°C phosphor temperature, enabling LEDs of all types, including mid-power LEDs, to operate at higher output and efficacy. The products are also versatile design tools for LEDs used in displays like TVs and tablets.
According to a survey this past March by the lighting manufacturer Osram Sylvania, the penetration of incandescent light bulbs in American homes has dropped significantly in the past year. The survey found that 29 percent of U.S. households now are free of incandescent bulbs and have adopted LEDs.
Edited by Rory J. Thompson