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CATEGORIES:Stokes Society\, Pembroke College
SUMMARY:Lighting the Future: Next Generation LED Lighting 
 to save Energy and Improve our Health - Professor 
 Sir Colin Humphreys
DTSTART;TZID=Europe/London:20140219T210000
DTEND;TZID=Europe/London:20140219T220000
UID:TALK49953AThttp://talks.cam.ac.uk
URL:http://talks.cam.ac.uk/talk/index/49953
DESCRIPTION:Solid-state lighting using GaN-based LEDs could re
 duce the global amount of electricity used for lig
 hting by 50%. Lighting would then use 10% of all e
 lectricity instead of the current 20%. In the UK t
 his would save £2 billion per annum in electricity
  costs\, and save 10% of carbon emissions from our
  power stations. The main factor preventing the wi
 despread use of LED lighting in our homes and offi
 ces is cost. The reason why GaN LEDs are relativel
 y expensive (a 40 Watt equivalent replacement LED 
 bulb costs about £15) is that they are grown on lo
 w-diameter sapphire or SiC substrates. The Cambrid
 ge GaN group has pioneered the growth of GaN LEDs 
 on 6-inch Si substrates\, which will substantially
  reduce the cost. The growth is difficult because 
 of the large difference in thermal expansion coeff
 icients (54%) of GaN and Si\, and the large lattic
 e mismatch (17%). This talk will describe how thes
 e difficulties have been overcome. A patent has be
 en filed and two spin-off companies set up. Plesse
 y acquired these in 2012 and is now manufacturing 
 GaN LEDs on 6-inch Si at its factory in Plymouth\,
  Devon. These are the world’s first commercially a
 vailable LEDs on 6-inch Si (and the first LEDs to 
 be manufactured in the UK).\n\nThis talk will also
  describe how LEDs can be used to optimise cancer 
 therapy\, improve our health and productivity\, an
 d even to replace WiFi.
LOCATION:Nihon Room\, Pembroke College
CONTACT:Graham Edgecombe
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