How to boost up IR LED transmitter distance?

[sharkfire]

I used IR LED as a transmitter and a photo transistor for the receiver.

I want to know how can I boost up the IR LED so that the receiver can still receive IR pulses from the IR LED, if their distance is about a foot and a half.

Thanks..

 

[FvM]

Re: IR Transmitter

1. use pulsed current up to the capacity of the used LED
2. use optics
3. use multple LEDs

 

[davidgrm]

Re: IR Transmitter

Modulate the signal that you are sending. Put an IR filter in front of the receiver, this will prevent it becoming saturated with ambient light. You can get one from an old remote or try using a piece of red plastic in front of a piece of green plastic. Reduce the resistor on your LED to about 100 ohm (modulating signals prevents it from overheating) Using these techniques I have managed distance up to about 20 feet