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The Presbylite II bifocal is the newest presbyopic design in North America. The lens is produced in Europe and is a very successful design there.
Figure 1 shows the unique design features of the Presbylite II. It most closely resembles a translating bifocal, but is really a hybrid design as the top 20% of the add segment is front aspheric for intermediate vision. The triangle shaped segment can accommodate 30 degrees of nasal rotation without visual distortion.
Figure 1 Figure 2A Figure 2B
  
What patients have commented on is the comfort of the lens and the high add power achieved with the Presbylite II.
The base curve is spherical and fit in an alignment manner. There is no corneal molding in this type of fitting as seen in many aspheric designs. Base toric design is also available.
The practitioner should choose the add power needed in spectacles for the Presbylite II. The design will deliver a true high add of up to +3.50. The fitter does not have to order a higher than needed add power because aspherics do not deliver the whole high add power.
The lens must center to perform optimally. The original version tended to ride to high on many patients. The Presbylite II design has engineered improper positioning out. See Figure 2A and 2B for the difference between Presbylite I and II.
Fitting has been made easy through custom software available at no charge. Just fill the Ks, refraction and ad power and the software computes the fit. The warranty pricing insures a successful fit.
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