Distance vision

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Your eye can focus on one distance at a time through accommodation. Standard full prescriptions have a minimum power of 0.25D, which would compensate for an edge of blur at 4 meters. 6 meters or 20 feet is considered as far as you possibly need to measure vision. Beyond that the number of the rods and cones in the back of your eye is a bigger limiting factor on vision than any tiny additional refraction bonus you could get.

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