High-Resolution Lenses and Higher-Order Aberrations

Do you have 20/20 vision while wearing glasses but still feel dissatisfied with your view? You may benefit from high-definition lenses.

Sometimes, higher-order aberrations can affect your vision, even if your eyeglasses fully correct your myopia, hyperopia, and/or astigmatism. These aberrations can be due to the optical characteristics of your eyes or may be caused by the optical limitations of conventional lenses.

But there’s good news! Recent advancements in lens manufacturing have produced new high-resolution lenses that can correct these aberrations, potentially providing you with sharper vision than you’ve ever had with previous eyewear. These lenses are designed to deliver sharper vision in all lighting conditions and reduce glare when driving at night and during other nighttime tasks.

Many high-definition eyewear brands are now available, including high-definition versions of high-index lenses, progressive lenses, and aspheric lenses.

Remember that to achieve the best vision and comfort, all high-definition lenses should have an anti-reflective (AR) coating to eliminate distracting reflections.

Freeform Lenses

The most popular type of high-resolution lens is called freeform lenses. The term "freeform" refers to the advanced manufacturing process that reduces higher-order aberrations such as spherical aberration that occur in eyeglass lenses produced using traditional lens manufacturing tools and processes.

High-definition lenses are designed to provide sharper vision in all conditions and reduce glare when driving at night.

With freeform lenses (also known as digital high-definition lenses), the lens fabrication from the wearer’s prescription is optimized with computer-controlled surfacing equipment, which is much more precise than conventional tools.

In fact, freeform technology can create lens surfaces with a power increment of 0.01 diopter (D), compared to the 0.125 to 0.25 D increments of conventional lens surfacing equipment.

The fabrication of some freeform, digital lenses also takes into account how the lenses are positioned in front of the wearer’s eyes when in frames, to provide the most accurate lens power and sharpest vision possible.

Other factors that may be considered in the lens customization process include the angle between the eye and the back surface of the lens at different viewing positions (e.g., when the wearer looks to the side instead of straight through the center of the lens), frame size, and the position of the wearer’s pupils within the frame outline.

With these factors and possibly other elements taken into account during the design and manufacturing process, high-definition eyeglass lenses offer an unprecedented level of customization and can reduce or eliminate certain higher-order aberrations.

The precisely crafted and personalized surfaces of high-definition lenses can help reduce aberrations that limit the field of view and cause starburst effects, halos, and comet-like distortions of lights at night.

As a result, high-definition lenses can provide sharper image quality, better peripheral vision, improved contrast sensitivity, and less glare at night.

Popular High-Resolution Single Vision Lenses Include:

• Essilor Prencia DS (Essilor of France)
• Hoya NuLux EP (Hoya Vision Care)
• Shamir Autograph II SV (Shamir Insight)
• Clarlet Personal (Carl Zeiss Vision)
• Kodak 1.6 Blue UV link

Popular High-Resolution Lenses for Hyperopia Correction Include:

• Hoyalux iD MyStyle (Hoya Vision Care)
• Seiko Supercede (Seiko Optical Products of America)
• Shamir Autograph II (Shamir Insight)
• Varilux Physio DRx (Essilor of America)
• Sola HDV (Carl Zeiss Vision)
• Zeiss Progressive Individual 2 (Carl Zeiss Vision)

Because creating high-definition lenses requires additional information beyond what is recorded on your eyeglass prescription, your optometrist will often take additional measurements when you select frames for yourself.

Sometimes, a proprietary measuring device is used to fit and fabricate a specific brand of high-resolution, freeform lenses.

One example is the Zeiss i.Terminal 2, an automated imaging system that measures several fitting parameters – including the distance between the wearer’s pupils (PD), fitting height, frame tilt (lens angle), and the distance between the back of the lens and the front of the eye (vertex distance) – to optimize the performance of Carl Zeiss Vision’s custom high-definition lens brand.

Another example is Essilor’s Visioffice 2 system. According to the company, this second-generation 3D patient measurement device provides eye care professionals with an accurate, consistent, and precise way to prescribe and fit high-resolution lenses personalized to each patient’s specific visual needs and frame choices. Visioffice 2 also features a frame selection module that allows patients to easily compare their appearance when wearing up to eight different frame styles.

Wavefront Lenses

Some lens manufacturers have introduced a further customized type of high-resolution lens called wavefront lenses.

Wavefront lenses are created with the help of the same sophisticated technology used to measure the optics of the eye before custom wavefront LASIK surgery: A computer-controlled device projects uniform light waves into the eye, reflecting off the retina and back to the "wavefront" of the light, which is analyzed to assess all optical defects – not just refractive errors but also higher-order aberrations.

In custom LASIK, these wavefront measurements are used to program the excimer laser to reshape the front surface of the eye. In wavefront eyeglass lenses, the measurements drive the computer-controlled manufacturing process to create high-resolution, customized lenses.

The first wavefront eyewear brand introduced in the U.S. was iZon High Resolution Lenses, manufactured by Ophthonix.

According to the company’s website, in simulated nighttime driving tests (55 mph in bright light conditions), subjects wearing iZon high-resolution lenses could detect, recognize, and react to pedestrians along the road an average of 20 feet earlier than drivers wearing conventional prescription lenses.

In addition to improving nighttime vision, iZon lenses also help correct vision problems that persist after LASIK and other refractive eye surgeries, the company states.

However, only a limited number of optometrists and ophthalmologists prescribe iZon wavefront lenses, and in October 2012, Ophthonix announced it was ceasing operations after 11 years in business.

In 2011, Carl Zeiss Vision introduced a wavefront high-resolution lens brand in the U.S. called i.Scription by Zeiss. Like iZon lenses, i.Scription by Zeiss lenses are designed to correct higher-order aberrations and provide sharper vision than conventional eyeglass lenses.

According to the company, i.Scription by Zeiss lenses also help wearers see better in low-light conditions and improve contrast as well as color vision.

To create i.Scription wavefront lenses by Zeiss, your eye measurements are taken by your eye care professional using the company’s proprietary i.Profiler Plus – a three-in-one automated device that measures refractive error, corneal topography, and higher-order aberrations. The wavefront data collected by the i.Profiler Plus is then sent to Zeiss’s optical laboratory to fabricate the custom high-resolution lenses.

Are You a Candidate for High-Resolution Lenses?

Virtually anyone who wears glasses for myopia is a good candidate for high-resolution eyewear, but those with higher prescriptions may notice greater benefits than those with only mild prescriptions.

Perhaps one of the best indicators that high-resolution lenses may be a good choice for you is if your optometrist or ophthalmologist tells you that you have healthy eyes and 20/20 vision, but you experience glare or your vision seems unclear.

If you are dissatisfied with the clarity of your vision while wearing your current glasses, ask your eye care professional if high-resolution lenses could provide sharper vision.

Cost of High-Resolution Lenses

Due to the complex technology used to design and manufacture freeform and wavefront lenses, as well as the additional time and equipment needed to fit them, you can expect to pay up to 25 to 30% more for high-resolution lenses compared to conventional lenses of the same material and style.

Although high-resolution lenses cost more than conventional eyeglass lenses, many who have tried them – especially those who have been disappointed by unclear vision while wearing previous glasses – find that freeform and wavefront lenses provide a significant improvement in clarity and comfort.

[For the latest news on high-resolution lenses and other types of eyewear lenses, check out What’s New in Eyewear Lenses.]