Homebrew PCBs

In a message dated 8/30/2004 11:01:28 PM Pacific Standard Time,  
ben_englund@... writes:

I've  heard that green LEDs can act as photodetectors.  They are cheap 
if  you could get them to work.  Then just put a bunch in a circle a  
detectors and one on a disc on the shaft as an emitter.  Anybody have  
any luck using LEDs as detectors?

Ben  Englund


----------------------------------------
 
Yes,
 
I have used "plain jane" red leds as photodetectors. A voltages is produced  
across the leads in response to direct sunlight. It appears to be fairly  
sensitive.
 
A different voltage (lower) was read with the LED exposed to light, but in  
the shade opposed to direct sun light.
 
Ken


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