I mean no disrespect, I make all these points strongly and firmly for the arguments sake, but clearly something doesn’t make sense to you about the fact the middle point of a line on a 45 degree angle is shorter than the middle point of a line on a 180 degree angle.
So why don’t we have a greater on screen IPD reading to account for real IPD measurements? We have a lesser one. It doesn’t add up by logic any other way besides the lenses are 10mm bigger than the software measurement given on screen.
I’ve studied all the wide-fov headsets extensively as well, each of them use different optics and screen tech so there is no point comparing them.