Why is IR for Easy Screen Turn On still on when screen is on?

[Bag of Leaves]

So, last night I happened to turn my phone towards my bedroom TV nine or ten feet away and noticed that the IR beam from Easy Screen Turn On (where you wave your hand over the phone to see the Lock Screen) was interacting with the IR repeater that I have on my wall-mounted TV due to the cable box and DVD player being in the closet. (The IR repeater has a blue LED that blinks whenever it receives an IR signal.) I didn't realize that the phone's IR beam would reach that far, but also my screen was turned on at the time, so was surprised that the IR beam was still on. I turned the Easy Screen Turn On feature off and the phone no longer sent out an IR signal (as seen by the light on my IR repeater), but it started sending a signal again as soon as I turned the feature back on, even though the screen was on.

Shouldn't the IR beam turn off when the screen is on, seeing as there's no point to it being on when the screen is on?