The next generation of LED lights will focus on beauty not energy savings.
The energy savings that once helped popularize LED lighting are now taken for granted, forcing manufacturers to find other selling points.
For the next generation of such lights, companies are starting to compete with offerings that show off the natural colors of objects and make them look more beautiful.
Citizen Electronics, part of the Citizen Watch group, has developed a blue light-emitting diode that illuminates objects more vividly. Fellow Japanese company Kyocera has debuted a residential-use violet LED that better approximates sunlight.
Citizen plans to begin mass production next spring of a blue-LED package that emits light with twice the chroma of its conventional products.
Chroma is the factor in light that makes objects appear more vividly beautiful, so the company sees this LED finding applications in spot lighting in such settings as museums and stores.
Lights based on blue LEDs are made by combining the blue-LED chip with phosphors in a package. The blue light passes through the phosphors to create the full spectrum of visible colors, or white light.
Increasing the chroma of the blue-LED package usually comes at the expense of energy-saving performance, since the efficiency of light emission declines. Citizen boosted chroma without sacrificing energy efficiency by carefully adjusting the types and blends of inorganic materials used for the phosphors and slightly altering the color of the light to raise the chroma of the red and green components.
Kyocera seeks to capitalize on violet LEDs. Working with furniture maker Arflex Japan, it has developed home lighting based on violet-LED packages that emit light closer to that from the sun. The first products came out in September.
The violet-LED chip is combined with red, green, and blue phosphors in the package to yield a full spectrum of wavelengths.
Kyocera already markets violet-LED packages used in museums and such industrial settings as production facilities where cars are painted. Now, the general public also gets a taste of how violet LEDs can mimic sunlight.
The violet-LED packages are still mass-produced in relatively small quantities, so prices are high. The residential fixtures released in September start at 280,000 yen ($2,720).
Soraa of the U.S. is also working on violet LEDs.
The company’s founders include Shuji Nakamura, the Nobel Prize-winning inventor of the blue LED. It is involved in everything from the production of chips to packages to finished LED lamps. Soraa has already sold its offerings to hotels, stores, museums and hospitals in Japan.
To help popularize violet LEDs, the company is working to cut costs. A California factory that makes the LED chips on 2-inch wafers will soon be joined by a plant in New York state handling 4-inch wafers. The larger wafers yield more LED chips, which will allow Soraa to lower unit costs.