After making lenses the same way for about a century by using simple spherical and toric (cylinder) surface geometry to correct complex aberrations, eyecare professionals (ECPs) can now fit their patients with more precise prescriptions using free-form technology. While progressive addition lenses (PALs) have been made with free-form technology for some time now, lens manufacturers are just beginning to introduce single vision lenses.
|With the Nulux ep Bi-Aspheric Single Vision Lens, each prescription is custom-surfaced using HOYA Free-Form Design Technology to be perfectly matched to each individual prescription.
Think of free-form single vision lenses as a full lens version of the upper portion of a free-form PAL. In other words, manufacturers have essentially taken the optical designs from the distance zone of a PAL and expanded it to fill the entire lens surface. This creates a lens that provides single vision wearers the same benefits presbyopes have been enjoying while expanding the market for free-form lenses to a huge demographic.
While some may argue that it’s overkill to correct single vision to 0.01D, others, such as Greg Ruden, President of Expert Optics, would say, “If we can provide the best vision possible, why not offer that to patients and let them decide, especially when you consider that the additional cost of free-form single vision lenses is only about a dollar more per month.” It’s up to ECPs to make patients aware and let them decide if they want the more precise vision they can achieve using free-form technology.
“People have no problem spending four grand on a high-definition TV,” said Patrick Muglia, Product Manager of Kaenon Polarized, which offers a lens blank in its proprietary SR-91® material, for use with both single vision or progressive lenses. “The customer has already been educated by a barrage
of high-definition TV marketing about the fact that better vision exists. Now the ECP just needs to connect the dots with the customer that free-form offers the same visual improvement to patients.”
After establishing a presence in the progressive market with free-form technology, many lens manufacturers have now introduced single vision lenses made to the same precision. Available free-form single lenses include the ZEISS Individual™ SV and the ZEISS 3DSV from Carl Zeiss Vision, Inc.; the Super MV 1.67 from Seiko Optical Products of America, Inc.; iZon® ML and SL High Resolution Single Vision Lenses from Ophthonix, Inc.; Augen HD Single Vision Lenses from Augen Optics; the Optixx upgrade® from ProFit Optix; and the Nulux ep from HOYA VISION CARE, North America.
Zeiss offers two lenses because “Many ECPs have asked us to provide more customized options,” said Fred Howard, Carl Zeiss Vision’s President—Americas-Pacific. “Our 100% customized portfolio allows them to offer every patient an upgrade from their current eyewear.” The ZEISS Individual SV is precisely personalized for Rx and position of wear, while the ZEISS 3DSV is customized for the patient’s Rx.
The Seiko Super MV 1.67’s combination of a patented low base curve and free-form aspheric back-surface design virtually eliminates power error, distortion, and marginal astigmatism, according to the company. “The front surface includes Seiko’s exclusive 10mm spherical fitting button, and the free-form back surface provides precise aspheric/atoric compensation calculated for the patient’s individual Rx,” said Mike Rybacki, Seiko’s Senior VP of Sales & Marketing. “Unlike traditional aspheric lenses, which compensate for the primary aberrations in the spherical power, Super MV lenses correct these aberrations throughout the entire cylindrical axis, virtually enabling the edged lens to have ‘optical center vision’ everywhere. The result is exceptional clarity of vision throughout the lens, even with high power and cylinder.”
Ophthonix’s iZon ML and SL are wavefront-guided and based on second and sixth order aberrations of the eye, including spherical aberrations, coma, and trefoil. These aberrations, referred to as the optical fingerprint or iPrint™, are objectively measured by the Z-View® Aberrometer, which contains a proprietary algorithm that analyzes and manipulates these measurements to determine the best sphero-cylindrical prescription that is surfaced onto the back surface of the lens using free-form processing. The iZon lenses have been clinically demonstrated at the University of Illinois at Chicago to significantly improve a patient’s contrast, glare, and low luminance acuity. Additionally, the iZon ML Lens was clinically tested by the U.S. Navy at San Diego with an FDA-validated night driving simulator and determined to improve reaction time by 20 ft. when driving at night, with glare, at 55 mph.
The Optixx upgrade lens from ProFit Optix “is based on a three-dimensional xyz system,” according to the company. “The backside of the lens is divided in more than 100,000 pixels, which are calculated individually. This, combined with Optixx’s unique optical optimization technology which calculates the lens according to the patient’s chosen frame shape, results in a distortion-free lens customized for each individual patient.”
Last summer, Essilor of America, Inc. introduced Essilor 360°™ lenses—its first single vision lenses made with W.A.V.E. Technology™: Wavefront Advanced Vision Enhancement. Ac-cording to the company, “W.A.V.E. Technology detects and removes lens aberrations, resulting in sharper visual performance in Essilor 360° lenses. The lenses also offer full backside optimization with the Point-by-Point Prescription Mapping™ lenses and create a unique aspheric backside surface optimized for each prescription. Essilor 360° lenses provide a wider field of vision, sharper vision across the entire lens, increased contrast sensitivity, superior clarity in low light conditions and the ability to see more vivid colors and details, for every wearer, but especially for patients who have a high prescription (above +/-3.00D sphere and/or -1.00D cylinder).”
Shamir Insight, Inc. offers a free-form blank that can be used for both single vision or progressive lenses—The Freeform Blank™, a Shamir Freeform® Certified Single Vision Blank. According to Matt Lytle, Shamir’s VP of Marketing, “Our Prescriptor® software (which is used to grind Shamir Freeform designs) utilizes the front true curve of the single vision lens upon which to base its grinding calculations. If the lens is not manufactured to the same specifications as what Prescriptor needs, it will result in a finished lens that may cause issues for the patient. Therefore, it is best to use the Shamir Freeform Blank on all Shamir Freeform jobs to produce superior optics.”
With PALs having already established a free-form foothold, it’s time for single vision to follow in their footsteps.
John Sailer is Senior Editor of Vision Care Product News.
WHERE TO FIND IT
866-284-3611 • augenoptics.com
Carl Zeiss Vision, Inc.
800-358-8258 • zeiss.com/lenses
Essilor of America, Inc.
800-542-5668 • essilorusa.com
HOYA VISION CARE, North America
877-528-1939 • hoyavision.com
866-KAENON-1 • kaenon.com
877-FOR-IZON • izonlens.com
866-996-7849 • profitoptix.com
Seiko Optical Products of America, Inc.
800-235-5367 • seikoeyewear.com
Shamir Insight, Inc.
877-514-8330 • shamirlens.com