There are a few factors that affect this. For simplicity’s sake, we will limit discussion to the horizontal direction (since the pixels are square anyway).
This is the simplest factor. The FOVE 0 screen has 2560x1440 pixels total, with each eye seeing half the screen, so there are 1280 horizontally per eye.
However, there are parts of the screen that cannot usually be seen because of the bounds of the lenses (typically about 10 percent on each side). So by dropping 20%, we get 1280 * 0.8 = 1024 pixels viewable under typical circumstances.
The FOV varies depending on the user’s facial structure and the mount position. However, if you take a typical FOV of 95 degrees, you get 95° / 1024pixels = ~0.093° degrees per pixel on average.
However, due to the nature of geometry, the pixels in the middle will have a larger angular span than the pixels in the periphery.
To make matters more complicated, the screen is viewed through a lens that causes pincushion distortion. You generally will not notice this because our compositor adds barrel distortion to the image displayed, which in turn compensates for the lens distortion. Nonetheless, a larger area of physical screen pixels is concentrated in the center, resulting in an angular size that is smaller in the center and larger towards the edges.
This can be complicated to calculate, but as an initial approximation, you can say this negates the geometric effect above. In this case, we land on 0.093 degrees per pixel.
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