Graphics Horse
Member
I think I've got it mixed up with lenticular -- a parallax barrier is just very precisely placed black stripes. But I'm still reasonably sure that it doesn't switch anything. What would it switch? The stripes don't need to move around at all. You could gain perceived backlight intensity in pure 2D mode if you could make them go away entirely, but another LCD layer seems like complete overkill just for that.
It improves picture quality when it's turned off, otherwise the screen brightness would wobble up and down as you move your head slightly. It only has a single on/off state, it's not actively doing anything when it's on apart from being there. It's not complicated like dot matrix layer either, just long black lines, probably all controlled as a single cell/element.