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All things pertaining to wireless and RF links
By rupamc6
#195124
Hello everyone, I wish to transfer power at a distance of 10-15 feet using Infrared diode/LED. I need 3-4V at receiver side. I have used normal IR diode of AC remote control, modulated by 38 to 100 kHz as a transmitter and photo-diode as a receiver. I have already tried to transfer the power, but unable to do the same. Please suggest me about the required components and circuit for transferring the above mentioned power.
Can any one help me?
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By DanV
#195127
10 - 15 feet is a HUGE distance for this attempt.
Light intensity decreases inversely proportional to the square of the distance.
Increasing your distance by 2 times decreases the light intensity by 4 times.
Your chances of doing this are extremely slim.
Maybe a very large array of IR leds and a solar panel could provide something on the receiving end.
By rupamc6
#195134
DanV wrote:10 - 15 feet is a HUGE distance for this attempt.
Light intensity decreases inversely proportional to the square of the distance.
Increasing your distance by 2 times decreases the light intensity by 4 times.
Your chances of doing this are extremely slim.
Maybe a very large array of IR leds and a solar panel could provide something on the receiving end.
I have supplied power to IR LED from function generator.
Then what will be the input current to get the result. And how?
By n1ist
#195136
Once again, what exactly are you trying to do? You haven't mentioned how much power you are looking to transfer. Also, why are you modulating the light source? That just turns it off for part of the time, reducing available light.

Are you actually trying to transfer power, or are you making a beam-break or burglar alarm detector? If the latter, you can do it but will need optics and good alignment. For the former, you are probably looking at large optics, high powered lasers, or 1000W incandescent bulbs..

/mike
By neverdie
#195559
Maybe try solar panels? Perhaps IR will excite them as much as visible light. Worth a try. You could use a columinator on your IR beam to help mitigate the square of the distance issue. Or preferably use an IR laser. As long as price and efficiency don't matter much, I'd say it's do-able.