Luis Moreira wrote:
> Hi All,
> I am doing this project where I need to transmit and receive IR on the
> 950nm band (other bands acceptable as long as I can get matching TX and
> RX).
> I will be transmitting a 250uS pulse every 250mS. 
> I don't want a module, I need a photodiode or a phototransistor with at
> least 30 degree tx rx angle.
> I got some already which at first seamed ok but the sensitivity angle is
> 15 degrees and do not have that much of a range. I need the same range
> as a TV remote control (across the room kind of thing).
> Do I need some kind of lens?
> Best regards
> 		Luis  
> 

Luis,
The IR receiver modules have great sensitivity because the IR 
transmitter uses a carrier - often around 38KHz.  The receiver uses AC 
coupled stages with *extremely high* gain along with a bandpass filter 
at the carrier frequency.

Trying to match that performance with your .1% duty cycle method will be 
challenging.  Good luck!

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