If you look at the info graphics at KS page about brain warp you notice that it means rendering frames for left and right eye in “leapfrogging” fashion. The frame rates visible by each eye remain the same, the time point however are shifted for T/2 (where T is 1/F, F is refresh rate).
To give an example:
t=0, left eye is rendered
t=T/2, right eye is rendered
t=T, left eye is rendered
t=T+T/2, right eye is rendered
etc.
Refresh rate observed by left eye is 1/(T-0) = 1/T = F
Refresh rate observed by right eye is 1/(T+T/2-T/2) = 1/T = F
Which means F per eye.
Now from the global system perspective, the displayed information changes, twice as fast, because the left and right eyes are interleaved. So we can say the overall system refresh rate is 1/(T/2) = 2F.
If you assign F=75 Hz per eye, you get overall refresh rate 275=150 Hz, for F=90 Hz, you get overall refresh rate 180 Hz.
So far it is just playing with numbers, to explain “per eye” and “with brainwarp”. It does not explain whether brain warp is actually good for anything or not (I have my doubts). On the other hand, what Pimax wrote in the line you quoted and what they showed in the info graphics is technically coherent and correct. You do not need to make it more complex and convoluted by trying to relate it to Pimax 4K headset tech, which is clearly quite different.
I made a mistake. If you use low persistence backlight you don’t need async 90 as on Pimax 4K. And 8K don’t use shutters, shutters are needed when you don’t have real CLPL. My bad on that.
Now here is the thing, since you can feed actually 60Hz input sync on one eye, you just turn off backlight after half of simulated refresh interval(11ms/90Hz per eye simulated), so display 60Hz for 1/180 5.5ms, and while you do that, display in that same interval 60Hz input on other eye, you will fool the brain that it is seeing 90Hz. Because it gets actually data from game world(render in engine) with delay of 11ms, just not from same eye perspective. You will have 11ms delay per eye, instead of 16.6ms delay between both eyes. I will write detailed with time diagram when I get time. But I am 99% sure it can be used to fool the brain that 60FPS is 90FPS, at least in theory.
They say that each eye renders half of a frame, but not of the same frame.
Nor do they seem to use shutters; they use low persistence displays. The shutters would obscure the displays and these are as bright as some OLEDs.
I think you take it for granted that the same frame is always drawn for both eyes and that there are shutters, it seems to me that Pimax does not do any of those things.
Sometimes these sort of maneuvers (withholding key aspects) is sort of a speculation agitator. It keeps the buzz, hype and outlandish to rational theories going until they come out and say “hey your mostly wrong, we did it!”.
Ok, you win, you know more about subject than me. You have knowledge about how Brainwarp works with 8K, something that only exists as idea ATM. I have wrong assumption about that idea, when idea becomes reality, come again and read my diagram. If wrong, input is 90FPS, on output 180Hz I will admit I was wrong. 90FPS as what is render by GPU in game engine, not 90FPS that is made with ASW/ATW/reprojection etc.
