PRACTICE / LEDs, photodiodes and solar cells

The dark current is not the light signal

A photodiode reads 0.40 μA in the dark and 7.60 μA when illuminated. Both readings use the same reverse-current-magnitude convention. At this wavelength its calibrated responsivity is 0.60 A/W.

What optical power is incident on the detector?

1. A$12.0\ \mathrm{\mu W}$
2. B$12.667\ldots\ \mathrm{\mu W}$
3. C$4.32\ \mathrm{\mu W}$
4. D$0.667\ldots\ \mathrm{\mu W}$

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