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When a constant d.c. drive current is applied to device, the optical o/p power is 320 μm. Determine optical o/p power when device is modulated at frequency 30 MHz with minority carrier recombination lifetime of LED i.e. 5ns.

When a constant d.c. drive current is applied to device, the optical o/p power is 320 μm. Determine optical o/p power when device is modulated at frequency 30 MHz with minority carrier recombination lifetime of LED i.e. 5ns. Correct Answer 2.29*10-4

The output o/p at 30 MHz is Pc(30 MHz) = Pdc/(1+(wΓi)2)1/2 = 320*10-6/(1+(2π*30*10-6*5*10-9)2)1/2 = 2.29*10-4W.

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