Free-form Lenses & Digital Centration Devices (DCD)

Freeform since over 20 years

It is a bit more than 20 years since free-form generated progressive lenses were introduced into the marketplace. In their infancy, these lenses were looked upon as complex and expensive products, which many in both the industry and profession said would never catch on.

Well, it is evident that this production process has been adopted by all of the major manufacturers and is definitely here to stay. Not only has the freeform process been utilized for progressive lenses, but there is increasing use of the technology on every other type of spectacle lens, including an example of free-form bifocals.

What does the free-form Lens Technology mean to your patients and your business?

Free-form is a manufacturing technology that has been developed since the late 1980s where special Computer Numeric Controlled (CNC) machines are used to produce high precision lenses. Traditional lenses are surfaced on just one side and the best vision is in the center of the lens, while free-form lenses are surfaced on both sides customizing the lens to the patient’s prescription in a very precise manner. In fact, free-form technology can surface lenses in power increments of 0.01 diopter (D), compared with 0.125 to 0.25 D increments of conventional eyeglass lens tooling.

We can say that this technology can be considered as a gift to those opticians specializing in designing their patient’s eyewear.

How does a Digital Centration Device like visuReal fit in here?

As we already explained, free-form technology allows us to design customized lenses for every patient. Naturally, we need to take different and more precise frame measurements to allow the software designer to place optimum optics in the right places.

Which measurements are important?

In addition to the basic frame measurements besides monocular PD’s and segment heights, the following measurements are a must to truly customize the eyeglasses:

  • Position of Wear (PoW)
  • Vertex Distance
  • Pantoscopic Tilt
  • Panoramic Angle

For more info regarding measurements provided by the visuReal® equipment, please visit our blog entry
Necessary measurements for dispensing and fitting new glasses

What are the benefits of Freeform lenses?

  • Wider field of vision due to back surface design.
  • Maximized visual acuity at all distances.
  • Wider intermediate and near zones.
  • Minimal visual “swim and sway.”
  • Low levels of unwanted astigmatism.
  • Aspheric/atoric designs make the lenses thinner and flatter.
  • Reduction of Higher Order Aberrations.

When we are talking about free-form lenses, we are mainly thinking about PALs. However, single vision free-form lenses really create the Wow-effect. They offer clear, natural, and distortion-free vision all the way to the periphery of the lens.
Wherever you are with free-form technology right now, embrace it. It is the way of the future.

For more information or to address specific inquiries regarding our visuReal digital centration systems, please feel free to contact us.


photo source: Knecht und Müller