ir LEDS

[colubridae]

Hello everyone.
I’m new to arduino and electronics. I’m building a model railway (DCC) and am about to start on signalling. I’ve purchased a Mega arduino and intend to control light signals with trains interrupting beams from IR LEDS to IR photodiodes. Can anyone recommend a matched pair of LED/Photodiode?
The searching i’ve done online shows no combo with exact wavelength match. Is it necessary to have an exact peak wavelength match between LED/Photodiode?
Please.

(UK based.)

[Paul_B]

colubridae:
The searching i’ve done online shows no combo with exact wavelength match. Is it necessary to have an exact peak wavelength match between LED/Photodiode?

Absolutely not. Either IR or not. The only difference about an IR diode is that it has a filter to (more-or-less) reject visible light. So that is a very broad filter.

[colubridae]

Thanks Tesla.