Application presumably outdoors? 

Then I have to disappoint you: for one thing there is
no affordable filter that lets only infrared light through, but blocks visible light well enough.

Only filters are not enough. Therefore, other 
methods must be used to eliminate extraneous light:

- optical shielding, optical lenses
- modulation of the light source and then either narrowband evaluation in the receiver
  (this is how IR remote controls work) or even correlation with the source (optical measuring technique)

For this reason I use the circuit board with infrared proximity sensor and LED modulation of 38kHz.