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About Cree, Inc
Cree is a market-leading innovator of lighting- class LEDs, lighting products and
semiconductor products for power and radio frequency (RF) applications. Cree
believes in unlocking the power and potential of technology, enabling the world to
do more with less and transforming the way people experience light through highquality interior and exterior LED lighting solutions.
Cree's areas of business include LED lighting systems and bulbs, blue and green LED
chips, high-brightness LEDs, lighting-class power LEDs, and power-switching and
RF devices from Wolfspeed. Cree products are driving improvements in applications
such as indoor and outdoor general illumination, intelligent lighting, electronic signs,
video displays and signals, EV/HEVs, renewable energy, radar and
satellite communications.
Reflector used in led street light
Most LED street lights have a lens (lentille) on the LED panel, which is designed to
cast its light in a rectangular pattern, an advantage compared to traditional street
lights, which typically have a reflector on the back side of a high-pressure sodium
lamp. In this case, much of the luminance of the light is lost and produces light
pollution in the air and surrounding environment. Such street lights can also cause
glare for drivers and pedestrians.
Energy efficiency
The primary appeal of LED street lighting is energy efficiency compared to
conventional street lighting fixture technologies such as high pressure sodium (HPS)
and metal halide (MH). Research continues to improve the efficiency of newer
models of LED street lights.
An LED street light based on a 901-milliwatt output LED can normally produce the
same amount of (or higher) luminance as a traditional light, but requires only half of
the power consumption. LED lighting does not typically fail, but instead decreases in
output until it needs to be replaced. It is estimated that installation of energy
efficient street lighting in the 10 largest metropolitan areas in the U.S. could reduce
annual carbon dioxide emissions by 1.2 million metric tons, the equivalent of taking
212,000 vehicles off the road, and save at least $90 million annually in electricity
As LED lighting fixtures normally produce less illumination (eclairage), it is important
to use a well-distributed illumination pattern in order to produce the same
illumination as higher-lumen conventional fixtures. For example, different LEDs in
one fixture can target different points on the street.