Sorry but still not correct - an ir led has a nominal forward voltage drop of something around 1.2v-1.5v at 20ma, assuming 1.2v I can run that from 20v if I want (18.8v over the resistor making it 940R), 5v (3.8 v over the resistor making it 190R) or 3.3v (2.1v over the resistor making it 105R). Supply voltage has nothing to do with led voltage drop - all it changes is power dissipated by the series resistor (P=IV)
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@birty oops that was the wrong LED, very sorry for the confusion,
I was looking at UV Leds for some reason 
Yes, you were correctā¦ it is 1.5v forward for the IR ledā¦
something like this oneā¦
Was thinking more in the lines of this type of leds: https://no.rs-online.com/mobile/p/products/1880387/
Maximum Supply Voltage 3.2V
The specs are all in the data sheet - look for the forward voltage and pick the current you want to drive it with then work out the resistance needed. Those types of led require high current, heat sinks and usually constant current supplies to drive them though. Check to make sure you arenāt taking more power from the gpio pins than is available
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which is about 500mA max from the GPIO 5v and 3.3v pins eachā¦
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Hi! How do you get rid of the IR cut stuff? You mean phisically? Because there is a way in the docw to test the IR cut but it is not permanent.
Do you know how to activate/disable the IR filter using commands?