Humans’ eyes are set on the front of the face to allow binocular vision, where focus and fixation on an object by both eyes create a single visual image.
Problems with focus and fixation could result in blur, eyestrain or double vision.
To prevent binocular vision dysfunction the external eye muscles have to be in alignment, synchronised in gaze directions with healthy ocular pathways to the brain.
An optical prescription can often incorporate prism and corrective lenses properly centred can sometimes assist with the difficult problem of how to fix binocular double vision.
