Lets assume a HD reception of 1920 x 1080, and a TV that can display this.

Is this resolution per inch?

If yes, this means a 1" screen would have a TOTAL resolution of 1920x1080.
Then a 2" screen would hat a TOTAL resolution of 3840 x 2160.
Then a 70" screen would have a TOTAL resolution of 134400 x 75600.
(lets assume screens are square!)

My question is, what size does the film maker film the movie in?
If it's made in 35" then on a 70" tv the scaler would have to double the resolution?

I guess what I am trying to get at is perfect hd is 1920 x 1080 but at what size?

IS this making sense??