The Path to  Personalization
Thanks to the precision offered by freeform technology, options for super-customized PALs are on the rise
By Karlen McLean, ABOC, NCLC

Freeform lenses have opened the optical marketplace's eyes to the fact that progressive lenses can be customized beyond traditional base curves, typical measurements, and standardized "postage stamp" production.

That being said, however, it is important to understand that not all freeform PALs utilize the technology in the same way. Some PAL designs do, indeed, create totally personalized lenses, while some companies say they are using the technology to produce an improved product.

Looking ahead, optical experts predict that freeform lenses will rule the future of lens technology for many reasons.

• Base curves are no longer selected from stock parameters, but are created for each lens.
• Success with first-time wearers and former non-adapts increases, since the lenses adapt to patient's habits, not the other way around.
• Expansion of the visual field for all distances reduces peripheral blur with less swim.
• They feature larger and wider near and intermediate zones.
• Aspheric and/or atoric curves fine-tune vision in all zones, plus flatten and slim lenses for improved cosmetics and comfort with less weight.
• Fitting heights in the mid-teens accommodate most of today's small fashion frames.
• Computer-driven production allows for the most precise lens possible (see sidebar p. 39).
• Many freeform PALs are based on long, intensely detailed market research and clinical studies, making it easier to substantiate one-of-a-kind design to patients.
• And, in the case of the more personalized product, individualized wearing habits, such as visual tasks and/or head and eye movement, are combined with the Rx to create each lens.

FREEFORM OPTIONS

While dispensing freeform PALs may require new training or brush-up in measurements and, in some cases, specialized measuring tools, the ultra-personalized lenses should satisfy even the most persnickety patient--especially previous PAL non-adapts.

Here, we spotlight freeform PAL designs and attributes that are currently available in today's U.S. marketplace.

Carl Zeiss, Gradal Individual and Gradal Short i. The Zeiss Gradal Individual and Gradal Short i progressive lens designs are created using freeform technology, offering, "clarity, superior adaptability, and optimized wide viewing areas with virtually no distortions," company sources note.

After calculation, the progressive surface and back surface are three-dimensionally freeform diamond cut to shape, polished, and AR-coated. ECPs specify Rx, PD, fitting height, corneal vertex distance, pantoscopic angle, near distance, and frame shape to totally customize the lens.

A Zeiss Gradal Individual Fitting Tool helps verify the back vertex distance as well as the pantoscopic angle. A "zero" mm inset for monocular patients and specification of individual near working distance can further customize the lenses.

Minimum fitting heights are Gradal Individual: 18 mm (for traditional frame sizes); and Gradal Short i: 15mm (for small frame sizes). The lenses are currently available in 1.60 material with Zeiss Carat coating.

Gradal Individual and Short i lenses are produced at Carl Zeiss Optical's headquarters in Chester, Va., and can be ordered from participating Zeiss Partner laboratories.

Call 800-338-2984 or visit www.zeiss.com/lenses.

Essilor, Varilux Ipseo. While traditional Varilux lenses are based on a wearer's universal behavior, Essilor's Varilux Ipseo technology is based on the wearer's natural, unique physiological criteria plus Rx parameters and incorporates Essilor's Vision Print System (VPS).

The company provides ECPs with a VPS diagnostic device to measure unique wearer characteristics, including eye/head movement ratio and a stability coefficient. Combined with the patient's Rx, these measurements create a progressive surface specifically suited to the individual wearer's needs, company representatives say.

Design specifications take into account patient categories of eye movers versus head movers, with modified corridor length to compensate for the prismatic effects of the distance Rx and add power.

Head movers tend to be affected by lens swim and require softer and slower variations of power in the periphery, while eye movers receive an astigmatism-free area up to 60 percent wider than the design's baseline.

Varilux Ipseo is currently being tested in the U.S. in select markets through a specialized group of Varilux labs in Thin & Lite 1.67 with Crizal Alizé. Minimum recommended fitting height is 18mm. Further fun customization includes the patient's initials engraved on the lens.

Call 800-377-4567 or visit www.essilorusa.com.

Softer Dual Add technology reduces unwanted astigmatism by dividing and offsetting the progressive optics and distributing unwanted astigmatism between the front and back surfaces of the lens. Lens performance is backed by extensive clinical and marketplace testing.

Definity lenses also feature a Fourth Zone for larger frames. The Fourth Zone is located beneath the near zone and reduces the near add power to provide clearer vision when looking downward. Recommended fitting height is 18mm, but to best utilize the Fourth Zone, stay closer to a fitting height of 22 mm.

The lenses are available with Gemcoat multicoating, a premium AR and scratch-resistant technology, and are currently offered in CR 39 plastic, polycarbonate, 1.50 Transitions Gray, and high-index 1.60.

Definity lenses are made using The Spectacle Lens Group's proprietary manufacturing process in Roanoke, Va., and can be ordered direct or through Eyefinity and VSP laboratories.

Call 800-843-2020 or visit www.definity.com.

* Rodenstock North America, Multigressiv 2. Multigressiv 2 is created by a complex, computer- driven mathematical formula, which determines the precise combination of curves to optimize each lens. The lenses feature a fully aspheric front surface with optimized atoric curves on the back surface, allowing a smooth transition from distant to near focal points, a wider reading area, and enhanced peripheral vision.

Recommended fitting height is 18mm. Multigressiv 2 is currently available in 1.50 plastic, ColorMatic Extra photochromic gray or brown in 1.52, and 1.60 high-index.

The lenses are manufactured at Rodenstock's facility in Regen, Germany, and are available with SR and AR. Part of the Rodenstock Spectacle program, they can be paired with Rodenstock Spectacle frames.

Call 888-407-3937 or visit www.rodenstockusa.com.

Seiko Optical Products, 1.67 Super Proceed Internal. Seiko's 1.67 Super Proceed Internal places the progressive power on the back of the lens via freeform technology. The front surface is spherical. The freeform surface is fused with a toric surface on the back of the lens into a single complex curve, and then the aspheric compensation for each eye's Rx is added.

This helps eliminate power errors and ensure an expanded field of view, visual stability, and reduction in skew distortion, swim, and sway, according to the company. They estimate that more than 10 million lens combinations are possible.

It is available in two minimum fitting heights: 18mm and 16mm. All lenses are provided with Seiko high-impact factory AR and are available through authorized Seiko distributors.

Call 800-235-5367 or visit www.seikoeyewear.com.

Shamir Insight, Autograph. Autograph utilizes Shamir's advanced Direct Lens Technology combined with Eye Point Technology, a software program that designs a lens using an exact simulation of a human eye.

The lenses provide individualized design for every angle, vision zone, and Rx, resulting in enhanced peripheral vision, binocular vision, and visual clarity, the company reports.

Autograph is aspheric in all vision zones, creating a lens that is as thin as possible. Utilizing Eye Point Technology ensures the softest design for every zone. The company recommends a minimum fitting height of 18mm.

Autograph is currently available in CR 39 plastic and 1.60 high-index.

Insight Autograph lenses can be ordered from authorized Shamir labs.

Call 888-707-7760 or visit www.shamirlens.com.

The lens offers a balance of central and peripheral vision based on a 10-year wearer trial and ongoing studies on understanding progressive lens wearer's visual task requirements.

Utilizing SOLA's Design by Prescription technology, which adjusts design by base curve and add power for consistent performance, SOLAOne features a larger and wider intermediate area and a large, high, and wide near zone for a variety of reading tasks. The recommended minimum fitting height is 18mm.

SOLAOne is offered in Finalite 1.6 high-index, polycarbonate, polycarbonate Transitions Gray, standard plastic, and standard plastic Transitions Gray and Transitions Brown. SOLAOne HD is available with Teflon EasyCare coating in 1.67 high-index and 1.67 Transitions Gray.

The lenses are available in SOLA's Teflon EasyCare lens coating in all materials, and can be ordered from authorized SOLA labs.

Call 800-358-8258 or visit www.sola.com.