I opened an old point and shoot camera and removed the IR filter in the early 2000s but it seems to have caused autofocus problems. Purple images are unedited, converted to b&w with slight contrast adjustment.

It’s probably possible, but I suspect since the whole debacle of Sony selling camcorders with an IR night vision that also “let people see through clothes” when used during the day the manufacturers won’t make it easy to modify.

Why not just buy a sensor without the IR filter? They aren’t expensive. Or use an HD security camera that doesn’t have one? If you remove the filter from a phone’s camera, normal picture quality will suffer.

Many cameras have an infrared filter glass over the sensor that can be removed (may or may not be designed to be removed though), but that totally depends on the camera.

I just tested my phone camera with an infrared remote control aimed at the camera, apparently my phone camera wasn’t designed with that filter glass in the first place.

That’s just how easy it is to test, just point an IR remote at your camera and see if the camera can see it when you press a button on the remote.