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The efficiency of an LED for generating light is directly proportional to the

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  1. applied voltage
  2. current injected
  3. temperature
  4. level of doping. 

Answer (Detailed Solution Below)

Option 2 : current injected
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  • The efficiency of LEDs will be determined by the radiate recombination rate
  • Temperature influence the output power of an LED through its effects on the internal quantum efficiency of the device. 
  • The internal quantum efficiency of LEDs decreasing exponentially with increasing temperature. 
  • The efficiency of LED is directly proportional to the current injected. 
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