Retina Focus Principles

Competency
Backed by a decade of experience in optimizing progressive lenses prescription, based on individual positions of wear, Rodenstock presents a new set of mean fitting data for standard wearing positions. These new standards are collectively named Retina Focus Principles.

Position of Wear simply means that the prescription is optimized to standard or default data that is similar to the following values:
PD   = 63-65 mm
PT    = 8^o
FFA = 5^o
CVD = 13.5 mm

Hence, it means that when the above stated fitting criteria is met, lenses that are conceptualized in this manner will provide, better vision than any classic PAL design.

EyeLT

Whilst others remain around the freeform technology bottleneck, Rodenstock lances forward to futher develop additional PAL Optimization. And in 2011, introduced new research findings, that was never before thought possible, EyeLT:

1.  Eye LT 1 - Iso-Cyl neutralization
Whatever the PAL design, iso-cylinders existence are inevitable to create progression contours. This very same point is illustrate by diagrams on the left.

Rodenstock's R&D explored this issue and develop ways to neutralize these multiple values by changing to suitable axes and powers. By these neutralization, the effects of aberrations are greatly reduce.

2. Eye LT 2 - Listing Law

Recognizing what Listing's Law has indicated in that, when the eyes converges below the eye level to see near objects, both the eyes will rotate inwards, some changes to the actual Rx will be required to provide optimum near vision, especially to astigmats.  

3. Eye LT 3 - DN Eye

Development is in progress to combine the effects of wavefront values and abberometry for the perfect Progressive Add Lens design.

Soft & Hard PALs

Most PALs in the market are designed based on the distribution of distortion fields caused whilst creating the power progression.These diagrams will help illustrate the designs from some better known PAL providers.

And due to Position of Wear concepts and other optimizations, Rodenstock PAL mappings are as follows:

   

       

It is clearly realized that visual fields are not compromised, whilst lowering the progression contours to offer reduced peripheral distortions.