Distance vision

Revision as of 08:59, 1 June 2020 by Divenal (talk | contribs) (reworded the first paragraph. I was a bit confused about what it was trying to say. I hope I haven't lost some detail that I hadn't picked up on.)
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Distance vision is, for practical purposes, anything over 6 meters or 20 feet. Because the difference in lens power from 6m to infinity is less than 0.2D, the limiting factor is less about ability to focus than simply the resolution of the retina (the number of the rods and cones in the back of your eye).

As far as the ciliary muscle is concerned, your edge of blur is distance vision, no matter what the absolute distance, but you will have convergence at a near vision angle when looking at edge of blur through differentials. This is a possible mechanism of action for improvement, when the visual cortex notices the discrepancy between focus and convergence.

In the EndMyopia system, we use normalized glasses for outdoor work, for reading street signs, for looking out windows, and other distance vision tasks.

See Also

20-20-20 Rule