[nine_k]

This is fun! But I see it showing me a close-up view (smaller FOV) if I move my head back, and a wider view (larger FOV) if I bring my head closer. This is the opposite to what I'd expect: if I bring my head nearer to the screen, I should see a more detail, closer (narrower FOV).

[Wowfunhappy]

Your expectation doesn't match real life! Try it with a window. If you bring your head closer to the window, your FOV increases, ie you can see more of the scene outside the window.

[nine_k]

But there is no window. There is a box with a dragon in it. When I bring my eyes closer to the box, I expect to see more of the box, and more of the dragon. You can try it with any real box; substitute any appropriate object for the dragon. Pick your favorite 3D environment that features walls and dragons; notice how both grow, covering more of your FOV. This is what I expect to see as I draw closer to the screen.

[jeffhuys]

The screen is the window.

[il_nets]

Exactly what Wowfunhappy and jeffhuys are saying!