Varilux Physio f-360° technical information | Lens Design

Technical Features

The proven designs of Varilux Physio and Varilux Physio 360º are known and trusted by eye-care professionals and wearers worldwide. Essilor’s exclusive W.A.V.E Technology™ - pioneered in optics with Varilux Physio – was a breakthrough in the control of higher order aberrations and provided the benefit of High Resolution Vision™.

Research reveals the reduction of higher order aberrations of the lens are extremely important for the eye. In clinical studies Varilux Physio is proven to increase contrast sensitivity*, visual acuity and visual fields. Varilux Physio f-360° builds on the original design by taking into account five key wearing parameters and in doing so continues the designs success.

* Study conducted by Manhattan Vision Associates, Institute for Vision Research, New York - 2007

Enhanced High Resolution Vision

Further research has identified the benefits associated with the customization of the lens, allowing for an even higher quality of vision.

Wavefront analysis shows the impact of wearing parameters (such as pantoscopic tilt, vertex distance, wrap angle, pupillary distance and fitting height) on the optical performance of the lens. When the combination of these five parameters moves away from the standard, drawbacks occur, particularly in the near vision zone.

Drawbacks of Fitting Conditions

Pantoscopic Tilt	Insufficient tilt creates a narrower near zone with less of the wearer's required add power and higher peripheral aberrations.
Wrap Angle	Too much wrap narrows the near zone and dramatically increases peripheral aberrations.
Back Vertex Distance	An incorrect back vertex distance increases unwanted astigmatism especially in the near vision zone.

key: 1) Higher Order Aberrations, 2) Astigmatism, 3) Power Error / Defocus

Lens Calculation

To minimise the increased aberrations and unwanted shift caused by specific wearing conditions, Varilux engineers have taken into account the individual parameters of each wearer to calculate a lens which delivers the optimal quality wavefront to the individual.

The measurements of the five key fitting conditions are systematically allocated to the appropriate category. These categories then form the basis of the calculation to define the optimal quality wavefront for each wearer.

Lens Calculations

The five key dimensions: Back Vertex Distance, Pantoscopic Tilt, Wrap Angle, Fitting Height (R/L), Pupillary Distance (R/L)

Two Sophisticated Surfaces

As with all Varilux 360° digitally surfaced lenses, Essilor uses two complex surfaces of the lens to enhance design performance. With Varilux Physio the optical output is measured by the resultant wavefront. Varilux Physio f-360° now adds customisation by incorporating the five key wearing parameters.

The flexibility of Essilor's Advanced Digital Surfacing™ on the back surface allows for the addition of these parameters to the calculations and processing.

Dual Positioning System™ (DPS)

Being able to utilise the interaction of the two surfaces allows for the wearer's near vision position to be customised both in the horizontal and vertical direction according to their wearing parameters. The length of the progression is defined in the same way.

A minimum fitting height of 16mm is provided by the customisation process and the continuously variable near point position is reflected in the markings on the finished lens.

Dual Positioning System

Global Positioning System Analogy

The DPS (Dual Positioning System™) works like a Global Positioning System. GPS helps determine the precise positioning of the car, while DPS ensures the perfect positioning of the near vision area individually for each wearer.