Lens Types

ILT Lenses - Individual Lens Technology

Bespoke lenses for distortion free vision

The parameters required to produce a distortion free lens have, in the past, been so numerous that it has been impossible for lens manufacturers to supply a lens with no distortion. With the advancements in computer technology in the past few years, it is now possible to create a tailor made lens, individually designed not only to your prescription, but also specially adjusted to take into consideration the position the spectacles sit on your face. By measuring the distance the lens sits from the eye, and the angle it sits at (measurements which in the past lens designers have taken a national average) we can supply a custom made spectacle lens with practically no distortion.

Prior to ILT technology, lens designers have traditionally relied on a set of parameters, determined by a national average, as a basis for lens design.


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How it works

Like a camera, the eye has a film, called the retina. Unlike the film in a camera, the retina is spherical, like the inside of a ball.

The eyes focusing system converges light on the retina and this creates a clear image.
When the eye requires a corrective spectacle lens, the spectacle lens also creates an arc of focus.

Ideally, the arc of focus created by the spectacle lens should correspond perfectly with the retina of the eye.

The position of the arc of focus is controlled by the lens deisgners. The distance the lens sits from the eye, and the angle, both vertically and horizontally, determine the position of the arc. As these distances and angles are unknown to the designers, an average figure is taken. However, should your spectacle lens sit differently to that of the average, this has an adverse effect on the arc of focus.

The effect this has on higher prescription, especially for varifocals can be considerable. The distortion created by a varifocal on lower prescriptions looks something like this.

With higher prescription however, simply by the lens not sitting infront of the eye as the manufacturers intended, the distortion can be as much as below.

This results in a very small field of view, not only in the reading area, but in the distance as well.

ILT lenses, designed around not only your prescription, but the position they are worn within the spectacle frame, eliminating these distortions giving far superior peripheral vision.

Single Vision
Thinner & Lighter