Probably look for display artifacts (pixel borders)?
But a fixture that takes a good enough screen + enough distance to make the photographed pixels imperceptible is likely just a medium hurdle for a motivated person.
You probably can't fully avoid it but adding more sensors (depth) will make such a fixture quite a bit more expensive.
This is a known problem in this space called 're-broadcasting' do a Google patent search on Serelay and you'll see several solutions (including spoofing of other sensor metadata)
How do you stop someone from taking a picture of an AI picture? It will still come from the sensor.