As far as what I have read, I believe that One-Eye depicts the Dajjal and the people who follows him (or Dajjalian System). Dajjal and his followers can only see with one eye i-e physical eye and would only believe on those things which they will be able to see with their naked eyes.
On the other hand, a true Momin sees with two eyes, one is physical eye and the other is spritual eye. Quran also states that Allah has filled our heart with "NUR" and because of that light we are able to see at things spritually and that is also how we see Allah.
On the day of Judgment we will be walked thru a bridge that will lead to Heaven and under that bridge, there will be hell fire. The place will be so dark that if we bring our hands in front of us, we wont be able to see them. So, only people that were able to see with their spritual eye will be able to pass the bridge, and people who could only see with their naked physical eye will fall into the hell fire.
And Allah knows the best.