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Near Vision lenses are designed for intermediate and near vision (not distance and near as with traditional multifocals). When a lens style is identified as a Near Vision style in Rx-Universe, that implies several things:
- Lens is dispensed with a “distance” power and an add power.
- The add power is converted to a degression based on rules specific to that lens style.
- The lens blank with the specified degression is selected.
- Power is measured at the NEAR reference point, not the distance.
- Prism, however, is measured at the PRP (in the distance or intermediate section of the lens).
- True curve of the near vision blanks is at the NEAR reference point (not distance as with a regular progressive).
- Wrap compensation CANNOT be done on a near-vision lens.
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