HiI have recently done the esterman test at Specsavers. I was expecting it to be similar to the standard visual field test but with both eyes open.
However I was surprised to learn that the red light you focus on does not remain fixed in the centre but instead moves to the corners of the screen every minute or so. You are then given a couple of seconds to find it before the white lights start appearing again. What is the purpose of this?
Thanks.