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Rescuing 5 sources and tagging 0 as dead.) #IABot (v2.0.9.5 |
→History: Highly doubtful that the phosphors just create red and green. Also, "light that appears white" is just white light. No need for weasel words. |
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The first low-powered LEDs were developed in the early 1960s, and only produced light in the low, red frequencies of the spectrum. In 1968, the first commercial LED lamps were introduced: [[Hewlett-Packard]]'s [[LED display]],<ref name="Andrews">{{cite book |last1=Andrews |first1=David L. |title=Photonics, Volume 3: Photonics Technology and Instrumentation |date=2015 |publisher=[[John Wiley & Sons]] |isbn=9781118225547 |page=2 |url=https://books.google.com/books?id=mkqVBgAAQBAJ&pg=PA2}}</ref> which was developed under Howard C. Borden and Gerald P. Pighini, and [[Monsanto Company]]'s LED indicator lamp.<ref name="Andrews"/> However, early LED lamps were inefficient and could only display deep red colors, making them unsuitable for general lighting and restricting their usage to numeric displays and indicator lights.<ref name="Andrews"/>
{{anchor|Invention of the blue LED}}The first high-brightness [[blue LED]] was demonstrated by [[Shuji Nakamura]] of [[Nichia|Nichia Corporation]] in 1994.<ref name="Nakamura">{{cite journal |title=Candela-Class High-Brightness InGaN/AlGaN Double-Heterostructure Blue-Light-Emitting-Diodes |author1=Nakamura, S. |author2=Mukai, T. |author3=Senoh, M. |journal= Applied Physics Letters|year=1994 |volume=64 |page=1687|bibcode= 1994ApPhL..64.1687N |doi= 10.1063/1.111832 |issue=13}}</ref> [[Isamu Akasaki]], [[Hiroshi Amano]] and Nakamura were later awarded the 2014 [[Nobel Prize in Physics]] for the invention of the blue LED.<ref>{{Cite web |title=The 2014 Nobel Prize in Physics - Press release |url=https://www.nobelprize.org/prizes/physics/2014/press-release/ |access-date=2025-04-11 |website=NobelPrize.org |language=en-US}}</ref> The existence of blue LEDs and high-efficiency LEDs led to the development of the first 'white LED', which employed a phosphor coating to partially convert the emitted blue light to
Philips Lighting ceased research on compact fluorescents in 2008 and began devoting the bulk of its research and development budget to solid-state lighting.<ref name=":0">{{Cite news |last=Taub |first=Eric A. |date=2008-07-28 |title=Fans of L.E.D.'s Say This Bulb's Time Has Come |url=https://www.nytimes.com/2008/07/28/technology/28led.html |access-date=2025-04-11 |work=The New York Times |language=en-US |issn=0362-4331}}</ref> On 24 September 2009, [[Philips]] Lighting North America became the first to submit lamps in the category to replace the standard 60 W A-19 "[[Edison screw]] fixture" light bulb,<ref name=":1">{{Cite news |last1=Taub |first1=Eric A. |last2=Vestel |first2=Leora Broydo |date=2009-09-25 |title=Build a Better Bulb for a $10 Million Prize |url=https://www.nytimes.com/2009/09/25/technology/25bulb.html |access-date=2025-04-11 |work=The New York Times |language=en-US |issn=0362-4331}}</ref> with a design based on their earlier "AmbientLED" consumer product. DOE awarded Philips the prize after 18 months of extensive testing. Many other similarly efficient products followed.<ref>{{Cite web |title=L Prize 60W Replacement Competition |url=https://www.energy.gov/eere/ssl/l-prize-60w-replacement-competition |access-date=2025-04-11 |website=Energy.gov |language=en}}</ref>
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