Straight Talk About Digital Lenses

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Shamir Creation and Freeform Optics are trademarks of Shamir Insight, Inc. For more information ... sors—Shamir Insight, Seiko Optical. Products, Essilor ... totally dependent parts: A progressive lens design; a .... their own in-house manufacturing loca- tions with ..... are instruments designed to measure panto- scopic tilt on ...
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Straight Talk About Digital Lenses Bringing you a greater understanding of the optical industry’s most talked about new technology.

Includes a free-form lens availability chart Brought to you by these industry innovators:

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Shamir Creation™. Flat And Exact.

Shamir Creation was developed with patented Freeform Optics™ to provide resolution up to six times more accurate than standard cast PALs. Shamir Creation features an extended base curve selection (up to 20 percent more than a leading competitor) providing flatter, cosmetically superior lenses (up to 40 percent flatter).

Simulation of 40% flatter lens.

This extensive base curve selection not only produces flatter lenses, but also results in an optimally divided prescription range that guarantees the best optical performance for each prescription.

Simulated Lower pixel resolution

Simulated Higher pixel resolution

Comparatively, one can make an analogy of Freeform Optics to the quality of a digital camera. The higher the pixel count, the higher the degree of resolution it facilitates and the more precise the level of visual fine-tuning it permits.

Shamir Creation is available in a wide range of materials from your Shamir Recreating Perfect Vision® partnering lab. For more information please contact your Shamir Account Executive at 877-514-8330 or your ReCreating Perfect Vision Partner Lab. Shamir Creation and Freeform Optics are trademarks of Shamir Insight, Inc.

CRE-ADS-0606

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Why Discuss Digital Lenses?

D

igital lens processing, also referred to as direct-to-surface processing and, most prevalently, freeform, has been the talk of the optical industry since it first emerged in the U.S. market just a few short years ago.

D

Jim Grootegoed

Ed De Gennaro

It has resulted in numerous lens advancements, and stands to be one of the most dynamic technological innovations in the manufacture of eyewear. For the first time, the wearer can actually receive a corrective lens designed expressly to accommodate his or her prescription, without the compromises previously necessitated by a conventional lens inventory built around an acceptable, though limited, number of base curves. Most of the major lens manufacturers have at least one product on the market that employs direct-to-surface processing, and many more such products are certain to follow. In fact, it is anticipated that direct-tosurface lenses will garner at least an 8% market share by the end of this decade. However, the rapid introduction of these products, many with differing technical and marketing claims, has created confusion among independent ECPs, labs, and optical retailers.

We hope to clear up some of that confusion with this editorial presentation and leave you with a clearer idea of the features and benefits of this exciting, new technology. In these pages, we describe the free-form process and how it works, explain how lens designers have addressed this new system of manufacture, and what it will mean for both lens casters and labs as the technology proliferates. We also discuss the significance of free-form to the practitioner and the patient, how this may change the dispensing process, and how to adjust the culture of your practice or retail environment to address it. This project would not have been possible without the support of its sponsors—Shamir Insight, Seiko Optical Products, Essilor and Carl Zeiss Vision—industry innovators all. We hope you find “Straight Talk about Digital Lenses” to be useful and illuminating. Thanks for reading… —Jim Grootegoed, Ed De Gennaro Project Editors

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I. Technology and Design

F

reeform®. Digitally Computed PAL. Individual PAL. Direct to surface technology. Digital Surfacing™. Directto-surface PAL. Vision First Design™. High Definition (HD) Technology. Personalized Progressive Lenses. These are but a few terms all being used to describe the same, new category of digital lenses generically called free-form.

F

Just what are “free-form” lenses? Confused? Well, you should be. The evolution of the “Individually Measured, Computed and Manufactured Progressive Addition Lens Using Computer Programs To Run Three-Axis Generators and Polishers to Provide the Wearer With an Optimized Lens Correction For A Visual Defect” is new and evolving. The acronym, “IMCMPALUCPTRTAGPPW WOLCFAVD” to describe the process might be a tad long and possibly difficult to remember, let alone explain to a patient. Therefore, the lens designers are coining—and trademarking or registering—terms and phrases like those above to describe and differentiate the freeform process.

be used to overcome optical aberrations and mechanical limitations of traditional surfacing. 2. “Framitized.” The PAL designs are modified to specific fitting, frame or adjustment characteristics. 3. “Personalized.” The PAL designs are created specifically to the prescription and individual viewing habits of the user. Each free-form design will include item one, above, and may, or may not, include item two and/or three. Without going into painful detail, any ophthalmic lens with refractive power placed in front of the eye will cause aberrations away from the optical center of the lens. Optical researchers have identified six aberrations (Spherical Aberration, Coma, Oblique Astigmatism, Chromatic Aberration, Curvature of Field, and Distortion), three of which they consider capable of modification to improve visual optics. Progressive addition lenses compound the problem inasmuch as they use asym-

metric curves to correct for distance, intermediate and near vision creating physical distortions on the lens surface.

History The design and manufacture of prescription ophthalmic lenses has really been one of compromise between good optics, cosmetic considerations, machinery limitations and inventory concerns. When a base curve is chosen for a particular power in order to minimize aberrations, the resulting lens is referred to as a “corrected curve” lens. The first attempt to design a lens to minimize peripheral aberrations was the Punktal series of single vision lenses from Carl Zeiss Optical, released in 1911, which changed the front base curve for every change in power. Because hundreds of base curves were necessary (not a practical option for a lab), American Optical followed in 1921 with their Tillyer “corrected curve” series of lenses that were flatter than “best form” designs for cos-

Seiko’s Internal Progessives But, in reality, what is “IMCMPALUCPTRTAGPPWWOLCFAVD” (free-form)? Basically, it consists of three separate but totally dependent parts: A progressive lens design; a software program; and very specific processing equipment.

Seiko is the patent holder of the world’s first internal progressive. Seiko’s internal progressives 3-dimensionally fuse a patient’s entire Rx (sphere, cylinder, axis, prism, and add power) onto the back surface of the lens. This process results in billions of customized, optically precise

Design Free-form lens design may be categorized into three basic types: 1. “Optimized.” Free-form design can PAGE 4

prescriptions and significantly expanded PAL visual zones (distance, intermediate and near).

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metic reasons and standardized on six base curves for inventory concerns. Bausch & Lomb followed shortly with their Orthogon lenses. Further, when surfacing compound lenses using hard fixed power tools (laps) with a standard index of 1.53, and lens materials other than glass, the computed powers will differ from the lap powers. As the power increases, the variance in calculated powers to lap powers increases. For example, the computed cylinder power may be -6.0626D. However, the laps are either -6.0000D or -6.1250D. When this occurs, choices have to be made to select one tool over the other. In either case, the resultant measured power

would be 0.07D off. When it came to multifocal lenses, additional compromises had to be made relative to intermediate and near vision placements. Insets were averaged. Segment lengths for PALs were also a matter of the manufacturer’s design ranging initially from about 22mm to 24mm in length and now modified to be as short as 13mm. Progressive lenses caused additional distortions because the powers for distance, intermediate and near were pushed all over the front surface of the lens. To summarize, the lenses we have been providing to our patients: • are uncorrected for optical aberra-

tions; • use lap powers in compound lenses, particularly for higher index materials, that may be off 0.07D; • have a fixed intermediate length not necessarily that of the patient’s desire; • use an arbitrary reading inset possibly adjusted for add power but not for PD. We, as an industry, have been providing compromised optics to our patients! Free-form lenses may be designed to correct, as much as is optically possible, these compromises resulting in significantly improved vision. The software can calculate the “perfect” curve(s) and cylinder cross-curve(s) to 1/100th of a diopter (0.01D), the optimal corridor

WEBINARS! Did You Miss the Webinar Presentation “Straight Talk about Digital Lenses” By Jim Grootegoed and Ed De Gennaro? It’s Available 24/7 at www.visioncareproducts.com/digital Learn more about how free-form lenses are made, the benefits to practitioner and patient and how you can take full advantage of this new technology.

Don’t be left in the dark about free-form! This event is sponsored by:

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length based upon the fitting height and frame “B” measurements, and the near vision inset based upon add power and PD. The free-form machinery available today can produce those curves.

What about the software? The key to the new “free-form” PAL lenses is the software that calculates the curves for the individual designs and drives the machinery to manufacture the lenses. The process starts with a theoretical design model, not unlike conventional PALs, using the front surface, the back surface or a combination of the surfaces. The optimal curves are calculated for every possible prescribed power at thousands of points on the lens surface resulting in a “point file” describing, in mathematical terms, the surface of the lens. Inasmuch as various lens materials all have different indexes of refraction, the optimal curves must be calculated for every material, too. This information is ultimately used to drive the production generator and polisher used to manufacture the lens. We have currently (September 2006) identified fifteen separate free-form designs (see Availability Chart, page 7), most from traditional lens manufacturers. Some designs will place both the progressive design and the power parameters on the backside. Other designs use both the front and back surface for powers and progressive designs. Some require a distance measurement as well to approximate the distance from the back surface of the lens to the front surface of the cornea—most do not. Others require the analysis and measurement of how the patient uses and moves his eyes under reading conditions as part of the lens calculations. Whatever the requirements, the resultant lens can be significantly more accurate than any lens currently available PAGE 6

on the market and provide the user with a new level of clarity.

What about the machinery necessary for free-form lenses? The calculations necessary for optimal lens designs date back to the 1800s but were limited by practical concerns, such as stocking inventory, and real barriers, including the processing machinery. The traditional surfacing machinery used to “generate” a curve was designed to be reliable, robust and reasonably accurate as the final curves were “fined” in using hard tools (laps). The resultant curves were always that of the tool. Precision tool making in other industries spawned the development of Computer Numeric Controlled (CNC) lathes using mathematical computations (a data file) and three or more axes (movements) to machine precision parts. The computer and semi-conductor industries are huge users of this technology, requiring extreme precision down to the nanometer level and extreme reliability to run 24/7. (One inch = 24,400,000 nanometers). This technology became the basis for free-form machines used to manufacture free-form lenses. In reality, CNC machinery can manufacture just about any shape imaginable; but it can only do this when its software properly drives the machines to construct a precision lens—a spherical, cylindrical, aspheric and individually designed freeform PAL. The key to today’s free-form process is the ability to deliver a near finished quality surface off the cutting generator. This is typically done by using two tools: a roughing tool to crib the lens and to generate the surface curves to a reasonable quality, then a single-point diamond tool to skim the surface of the lens leaving a finish that can be polished using a

CNC polisher and a soft, rotating tool also driven by three (or more) axis technology and the operating software. Power tolerances of less than one-one hundredth (1/100) of a diopter are possible. The surface smoothness necessary off the generator for polishing is 1 micron…1/25,400th of an inch!

State of the Union Most lens manufacturers are already providing their patented designs through their own in-house manufacturing locations with millions of satisfied patients already wearing free-form lenses worldwide. The software engineers have also worked closely with the CNC machine manufacturers to ensure process transference and viability. Some free-form designers prefer optimizing their designs to a specific equipment platform while others have validated their process with a number of equipment providers. Many of the designs are currently available to eye care professionals through their local laboratories, which will order the uncut lens from the lens manufacturer and provide the finishing services. Many of the holders of the freeform software are currently offering their calculation and machine software to manufacturing laboratories worldwide. The interest among the laboratories is extremely high, limited only by the cost of the investment (a minimum of $400,000 to well over $1 million). Most of the experts are predicting that freeform PAL lenses will constitute between 8% and 20% of the market within five years, certainly adequate to justify the investment.

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Currently Available Direct-To-Surface Lens Designs in the U.S. (Information supplied by lens manufacturers.) Manufacturer

Brand

(*) 1.50

Carl Zeiss Vision AO Easy HD SOLAOne HD Gradal Individual Gradal Short i Essilor DEFINITY x DEFINITY Short x Varilux Ipseo @ Variux Physio 360º @ Hoya Hoyalux i D Indo EyeMADE x(1.523) Seiko/Pentax Exceed Internal Succeed Internal x Pentax Perfas Shamir Autograph x Signet Armorlite KODAK Unique @

Transitions

x x @ @

Polarized

Trivex

SunSensors 1.56 Polycarb

x x @ @

(1)

Polycarb Transitions

1.60

1.60 Transitions

@ @ x x @ @ X

(2) x @

x @

@

@

@ (2)

(2)

x @

x @

x @

x @

1.67

1.67 Transitions

@ @ @

@ @

@ @ @ X @ x @ x @

@ @

1.70

1.74

(1) @

x x

Notes: x Indicates availability @ Indicates only available with factory AR Coating (1) Expected release 11/06 (2) First quarter 2007 (*) This column is intended as a guide. In the interests of brevity, not all manufacturers’ trademarked or registered names are noted for every material. Also, some manufacturers MAY use other than Transitions as their photochromic agent. Please contact the manufacturers directly for specific names and lens properties.

Manufacturer

Brand

Carl Zeiss Vision AO Easy HD

SOLAOne HD Gradal Individual

Essilor

Gradal Short i DEFINITY DEFINITY Short

Minimum Fitting Height 18mm 18mm 18mm

15mm 18mm 15mm

Varilux Ipseo 14, 16, 18mm Variux Physio 360º 17mm Hoya

Hoyalux i D

14, 16, 18mm

Indo

EyeMADE

16mm

Seiko/Pentax

Exceed Internal 14, 16, 18mm Succeed Internal 17, 19mm

Shamir

Pentax Perfas Autograph

Signet Armorlite KODAK Unique

12, 14, 16mm 16, 19mm 16, 19mm 16, 19mm 19mm 19mm 16, 19mm 16, 19mm 19mm 19mm 13mm

Free-form Lens Design Material (**) Back 1.67 & Back 1.67 Trans Back; 1.60 Front in 1.67 High Powers 1.60 PAL front 1.50 Add split Trans Power back Poly 1.60 Back See above PAL front See above Power back PAL and 1.67, 1.70 power split Back 1.523 1.60 1.67 Back See above Back 1.50 Poly 1.67 Back 1.67 Back 1.50 Back Trans Back Polarized Back Poly Back Poly Trans Back 1.60 Back 1.60 Trans Back 1.67 Back 1.67 Trans Back 1.50 Trans Polarized Trivex SunSens 1.56 Poly Poly Trans 1.60 1.60 Trans 1.67

Combined Power Range Power Sphere Cylinder Limitation +8.00 to -12.00D -4.00D +8.00 to -12.00D -4.00D +10.00 to -10.00D -6.00D +6.50 to -17.00D -6.00D

Add +1.00 to +3.50D +1.00 to +3.50D +0.75 to +3.50D +0.75 to +3.00D

+6.00 to -6.00D +6.00 to -10.00D +6.00 to -10.00D +4.00 to -5.00D +8.00 to -12.00D +6.00 to -10.00D +9.00 to -12.00D

-6.00D -4.00D -4.00D -2.00D -4.00D -4.00D -4.00D

+0.75 to +3.00D +1.00 to +3.00D +1.00 to +3.00D +1.00 to +3.00D +1.00 to +3.00D +0.75 to +3.50D +0.75 to +4.00D

+6.00 to -10.00D

-4.00D

+0.75 to +3.50D

+6.00 to -6.00D +7.00 to -12.00D +6.00 to -13.00D +6.00 to -10.00D +4.00 to -5.00D +5.00 to -7.00D +6.50 to -10.50D +6.00 to -10.00D +4.00 to -8.50D +4.00 to -8.50D +4.00 to -7.00D +6.00 to -10.00D +6.00 to -10.00D +6.00 to -10.00D +6.00 to -10.00D +6.00 to -12.50D +6.00 to -12.50D +6.50 to -9.50D +4.75 to -10.00D +4.75 to -8.75D +4.75 to -10.00D +5.25 to -10.00D +4.25 to -10.00D +4.25 to -10.00D +8.00 to -10.00D +6.25 to -10.00D +7.75 to -10.00D

-4.00D -4.00D -4.00D -4.00D -4.00D -4.00D -4.00D -5.00D -4.00D -4.00D -4.00D -4.00D -4.00D -4.00D -4.00D -4.00D -4.00D -4.00D -4.00D -4.00D -4.00D -4.00D -4.00D -4.00D -4.00D -4.00D -4.00D

+0.75 to +3.50D +0.75 to +3.50D +0.75 to +3.50D +0.50 to +3.50D +0.50 to +3.50D +0.50 to +3.50D +0.50 to +3.50D +0.50 to +3.50D +0.75 to +3.50D +0.75 to +3.50D +0.75 to +3.50D +0.75 to +3.50D +0.75 to +3.50D +0.75 to +3.50D +0.75 to +3.50D +0.75 to +3.50D +0.75 to +3.50D +1.00 to +3.00D +1.00 to +3.00D +1.00 to +3.00D +1.00 to +3.00D +1.00 to +3.00D +1.00 to +3.00D +1.00 to +3.00D +1.00 to +3.00D +1.00 to +3.00D +1.00 to +3.00D

-10.00 -7.00 -8.00 -10.50 -10.00

Comments

Standard fitting information acceptable but additional specifications as vertex distance, frame wrap and panto angle using their EyeTerminal will result in a more exact lens calc. Features a 4th ground level viewing zone named “Ground View Advantage.”

Requires use of the Varilux VisionPrint System.

Requires information from testing head/eye movements with their Visual Map.

Frame “B” dimension required.

(**) This column is intended as a guide. In the interests of brevity, not all manufacturers’ trademarked or registered names are noted for every material. Also, some manufacturers MAY use other than Transitions as their photochromic agent. Please contact the manufacturers directly for specific names and lens properties. PAGE 7

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II. The Patient

F

ree-form progressive lenses have a good number of advantages. Giving patients the right messages in the right way will enhance their understanding of the value these lenses provide while, at the same time, enhancing your professional abilities and your bottom line.

F

How do I explain the differences between these lenses and standard progressives in simple terms? As with any new technology, there is a learning curve for both the eyecare practitioner and the patient. Trying to convey confusing descriptions of how point files and free-form processing equipment create these lenses will only serve to confuse the patient. Instead, a simple, logical explanation is the best approach. Your goal should be to give them enough information to make them feel comfortable that they have received good value for their money. There is wide variation in the features and benefits this category of lenses provides, but as a group, free-form lenses maximize the design of the lens a patient buys. In other words, the free-form process brings out the potential in a lens design which can help it deliver clearer, sharper vision with wider fields of view. A number of them also offer an individualized prescription, which means the patient gets a highly accurate prescription. The best explanation of free-form lenses is that they represent the latest frontier in lens technology. With all the emphasis on advanced technology these days from things like iPods to cell phones, just about everyone wants to know they are purchasing the latest and

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greatest when they buy something. Progressive lenses are surely part of that trend. Most patients will be completely satisfied with this explanation. Before you can tackle the job of explaining free-form lenses to your patients, you need to understand the features and benefits of the process and the specific features and benefits of the lens product you’re recommending. While your explanation to the patient should be simple, it must be accurate. Your lab or lens manufacturer’s representative can help you with this information.

Will the patient appreciate the distinctions between these new lenses and conventional ones? In a word, yes. Well-designed, wellmeasured, and well-fitted free-form lenses can provide enhanced results over conventionally designed and produced progressive lenses. Will the results be dramatic for a -0.50 -0.75 x 180 wearer?

Perhaps not, but many eyecare professionals report that patients who have tried on free-form lenses for the first time have a startled reaction because their vision is so good. This is because the free-form process aids its progressive lens design to deliver crisper, sharper, bolder vision. For wearers, this means they receive advanced technology lenses that enhance vision over conventionally designed and processed progressives. First-time progressive lens wearers will appreciate this a great deal because it means they will spend little time adapting to the lens. Another reason free-form lenses provide this reaction is because they are produced using individualized curves determined by the patient’s prescription. Some free-form lenses like the Carl Zeiss Vision Gradal® Individual, Varilux® Ipseo™, and Seiko Succeed Internal Free-Form™ and Exceed Internal Free-Form™ are customized for

Shamir Autograph Part of the Shamir Freeform® Family, Shamir Autograph® exhibits the future of progressive lens design. Developed with Shamir’s proprietary Personalized Freeform® technology, Autograph provides a tailor-made lens, exclusive to the patient’s Rx. This customized lens assures the patient the highest level of optical accuracy (up to 1/100) and delivers a 20% wider field of vision with Shamir’s patented backsurface design.

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No Two Are Ever Alike Gradal® Individual and Gradal® Short

No two fingerprints or snowflakes are ever

with fitting heights starting at 15mm, enable you to

identical, and neither are your patients. That’s why

deliver perfect vision in both traditional and smaller

Zeiss developed breakthrough technology that

style frames. The result: individualized comfort and

creates a premium progressive lens for each

patient satisfaction. For more information on

individual patient. Gradal Individual allows you to

Gradal Individual and Gradal Short i, call

incorporate new measurements for truly

1-800-338-2984 or visit www.vision.zeiss.com.

individualized lenses. Plus, two channel lengths,

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the wearer. Based on the dimensions of the frame, these lenses adjust the lens’ design to customize and optimize it. For example, Individual has a fitting length that varies from 14mm to 20mm. Ipseo uses three fitting heights in 2mm increments—14mm, 16mm, and 18mm. Seiko’s Exceed has 14mm, 16mm, or 18mm minimum heights while its Succeed uses 17mm or 19mm. This design flexibility basically avoids the question of whether the lens is a long or short corridor lens. The design compensates the corridor and the optics of the lens simultaneously. Customizing the corridor length gives the patient exactly what he or she needs without going too long or too short. Experienced PAL patients may find that they no longer need to move their heads around to find the different visual fields; they are exactly where they should be. This means they can just drop their eyes instead of moving their head searching for “the right spot” to view an object.

Should I wear these lenses myself in order to comment on them? Yes—for two reasons. The best way to learn just how any lens performs is to wear it yourself and experience what it

can do. Think of it as a one person, one pair wearer trial with you as the subject. Make notes of the characteristics you find most appealing so you’ll be able to explain them to patients later. No one will do a better job of explaining the benefits of a pair of free-form lenses than a satisfied eyecare professional wearer. The other reason is that your patients expect you to be the eyewear expert in your office. If you’re a presbyope, many of them will ask you what progressive lenses you wear. Being able to say to them that you wear the newest and most advanced style of lenses is invaluable. You can even take yours off and say, “See, these are my free-form XYZ lenses.” Use them as a demo as you explain the advanced features of the lenses.

How can I justify the cost differential to the patient? For most patients, cost is not the issue when buying eyewear; the issue is receiving value for the money they spend. This is especially true of lenses when patients view them as the medically necessary portion of their eyewear. They might cut back a bit on their frame, but the lenses are the main reason they obtain eyewear. The more features and benefits a

product provides; the more value it delivers. The more value it delivers, the more the patient will want to buy it. The key in justifying the cost of free-form lenses is to detail the features and benefits of them to the patient. With each one mentioned and explained, the value of the lenses becomes greater and makes the lenses more appealing.

Do lens add-ons help the lenses perform better? Good quality lens add-ons can enhance free-form lenses just like they do any other lenses. Of course, the most obvious one is an oleophobic/hydrophobic antireflective treatment. In fact, some freeform lenses like Varilux® Physio™ 360°™, Signet Armorlite’s KODAK Unique, and Seiko’s Exceed Internal Free-Form (and other free-form lenses) are only available with anti-reflective treatment. Since you are already giving your patient advanced technology designed and processed free-form lenses, why would you want to have them annoyed by distracting, troublesome and sight-reducing surface reflections? This is especially true of free-form lenses made with high-index lens materials.

III. Prescribing and Dispensing

D D

o I need to refract the patient differently for free-form lenses? No, there is no difference in the refracting process for these lenses. Standard refracting equipment and other ophthalmic instrumentation should be used. Of course, you will want to ask questions

PAGE 10

about the patient’s lifestyle, viewing needs and viewing distances, special concerns like not wanting to drop their eyes too far into the lens when doing near work, and other questions you would normally ask before performing a refraction. The more accurate and personalized the

prescription is for the patient, the higher level of satisfaction he will have with his free-form lenses.

What information do I need to provide to the surfacing laboratory? Some free-form lenses require no more

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than the usual measures you currently provide for traditional progressive lenses—the patient’s monocular PD and monocular segment height along with the frame data and other eyewear related information (e.g. material, tint, etc.). Some lenses like the Carl Zeiss Vision Gradal® Individual allow you to supply additional measurements for more precise customization, including vertex distance, pantoscopic tilt and face form (also known as “wrap” these days) tilt. Varilux® Ipseo™ and Indo’s EyeMADE® offer additional instrumentation to measure how the patient uses his or her eyes. This information is then incorporated with the prescription into the design. Essilor’s DEFINITY™ asks ECPs to pick one of eight standard frame shapes and to include this information on the patient’s prescription. While all surfacing laboratories will want to know the frame’s A, B, ED and DBL measurements to determine if the lens will cut out in the frame, some will use these data to customize the design for the wearer. The Varilux Ipseo and the Signet Armorlite KODAK Unique are good examples of this. Based on the fitting height you supply, the lens’ corridor length will be adjusted so that it is optimized for the patient. Remember that one of the biggest contributors to progressive lens failures is inaccurate measurements, especially segment heights and monocular PDs. As with any progressive addition lens, use a corneal reflex pupilometer to obtain monocular PDs. When using a ruler to take segment heights, be sure to pre-adjust the frame as if you were dispensing the eyewear. This is particularly important for those lenses that require pantoscopic tilt, face form tilt (wrap) and vertex distance measurements. Sit in front of the patient so that you are on the same eye level. This avoids parallax and inaccuracies. Once you begin to take the fitting height measurements, do not move your head, just your ruler hand from eye to eye. If you move your head, you will have broken your alignment to the patient, creating the potential for inconsistent measurements. Take fitting height readings at least twice to ensure they are the same. This also helps to avoid errors.

Do I need any special equipment to measure the patient for free-form lenses? In most cases, you do not need any additional instrumentation or equipment other than the usual complement of measuring devices, such a corneal reflex pupilometer and a PD ruler. For Varilux Ipseo, a special eye tracking device called the VisionPrint System® is used to measure the patient’s unique head and eye movements. These data are used to personalize the lens for the patient’s unique viewing habits during manufac-

ECP Perceptions of Free-Form Lenses These results were generated via audience survey during the webinar presentation of “Straight Talk About Digital Lenses,” 9/28/06. 1. Which statement best describes you? a. I have dispensed free-form progressives and feel they are superior to conventional PALs. b. I have dispensed free-form A progressives and feel they are no better than conventional PALs. 32% c. I have not dispensed free-form progressives E C but I plan to do so soon. 34% d. I have not dispensed 34% free-form progressives and do not plan to do so. e. I do not prescribe or dispense lenses. Total respondents: 56

2. What do you perceive to be the major benefit of free form lenses? a. More accurate Rx for the patient. b. Greater profit margin for dispensers c. A solution for high powered or difficult prescriptions. d. Don’t know.

A 87%

C 9% D 4% Total respondents: 53 3. When you hear the term “free form processing,” what do you think it means? a. A new way to make progressive lenses. b. A new way to make all lenses. c. Computer lens designing. d. Taking slabs of plastic and cutting lenses out of them. e. All of the above.

E 68% A 14%

C 9% B 9%

Total respondents: 57 PAGE 11

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ture. If you use this lens, you will want this instrument, which is available through Essilor. Some free-form lenses require pantoscopic tilt and vertex distance measurements. You may also be asked for a face form tilt measurement. A distometer can be used to measure vertex distance, and some ECPs use a PD ruler for this measurement. There are instruments designed to measure pantoscopic tilt on the market. Face form tilt can be estimated using a chart-like device. Manufacturers are coming onto the market with electronic measuring devices that take patient fitting measurements automatically. For example, the Carl Zeiss Vision’s Eye Terminal measures monocular fitting heights, monocular PDs, pantoscopic tilt, face form tilt, and vertex distance, all with electronic accuracy.

Will recommending free-form lenses add to my chair time? No, prescribing free-form lenses will not add any time to your normal examination routine if you are already performing a patient interview before you refract. For some lenses, a couple of additional minutes may be added to the dispensing routine for one or more additional measurements needed.

Are free-form lenses suitable for all patients? Yes, free-form lenses are effective for nearly every presbyopic patient, not just because of their advanced free-form processing, but because, in most cases, manufacturers are developing advanced designs to use with free-form processing techniques. This means that patients receive the latest in lens design and technology along with the most accurate method for processing these lenses. One major advantage of free-form lenses is their ability to be customized for the patient’s individual frame and Rx. This kind of optics benefits just about everyone. It is especially suitable for those with strong prescriptions, those who have had poor results with prior progressive lens designs and those with high cylinder in the prescription. Anyone who wants the best optical performance available in today’s progressive lenses is a suitable candidate for customized freeform lenses. Those who want the latest advancements in lens technology are also suitable candidates for free-form lenses.

Free-form lenses are no more difficult to recommend, demonstrate, measure, and order than any other progressive addition lens. As with any progressive lens, good dispensing procedures are called for. Keep the vertex distance as close to the eyes as possible while avoiding the eye lashes from touching the back surface of the lenses. Be sure to include adequate pantoscopic tilt and use face form tilt to position the lenses properly in front of the eyes. Some free-form lens designs require additional measurements, but these can be learned, practiced, and perfected in less than 30 minutes. Even staff members who are not certified or licensed dispensing personnel will not have difficulty working with these lenses once they have learned the fundamentals. This knowledge and training can be obtained in printed form from lens manufacturers, professional journals, and continuing education articles. Hands-on training can be provided by optical laboratories, lens companies, and co-workers. In short, free-form lenses are just as easy to work with as traditional progressive lenses.

I’ve heard that free-form lenses may be too complicated for staff to dispense. Is this true?

IV. Ordering, Fees, and Other Questions

D D

o I obtain free-form lenses the way I do other lens products? Yes, simply call an authorized surfacing lab or, in some cases, the lens supplier for the lens brand you wish to obtain, and they will handle your order. Remember that some lenses require

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additional measurements over the standard monocular PD and segment height used by conventional progressive lenses. Not sending these in at the time of ordering will only delay processing. Some lenses are also only available with certain treatments included. For

instance, Varilux® Physio™ 360°™ and Varilux® Physio™ are sold with Crizal Alizé with Clear Guard™, Essilor’s topof-the-line anti-reflective treatment— you can’t get the lens any other way. The Pentax Perfas Internal Free-Form™ is sold uncut with AR treatment already

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on it. SOLAOne™ HD and AO Easy HD from Carl Zeiss Vision both come only with Teflon® Clear Coat while their Gradal® Individual and Gradal® Short i are produced with the Zeiss Carat® Advantage AR coating. Be sure to know your product’s availability before you recommend it to a patient to avoid disappointment and dissatisfaction. A few quick mouse clicks on a manufacturer’s or lab’s Web site or a fast phone call will usually get you the answers you need in minutes.

Should the lab finish the lenses or can I do this? This is a decision you’ll have to make. Nearly all of the lenses are available uncut (so you can cut, edge, and finish them). While a good number of optical offices have finishing capabilities, most laboratories will be pleased to fabricate your complete order including surfacing the lenses, cutting and edging, drilling, mounting, tinting, and hard coating them. Some of these lenses can only be ordered with AR treatments. For those that are available without it, your lab will arrange to have that done for you. Of course, some laboratories strictly produce uncut lenses for you to edge. If you’re comfortable edging and finishing your own lenses, be sure to ask your lab about this option when you

order the lenses. Be aware that some lenses are only available directly from the manufacturer itself (not through authorized labs). For example, the Pentax Perfas Internal FreeForm is produced by Seiko/Pentax and sold uncut (you have to do the finishing lab work on it).

Should I set my fees for these lenses the same way I do now for other lenses? How much you charge for your products and services is a very individual choice. There is no magic formula to follow that works for every office and every patient. If you have a fee formula for lenses that you have successfully followed, by all means, continue to use it with free-form lenses. Some eyecare professionals have the impression that free-form lenses are much more expensive than traditional progressives at the wholesale level and therefore cannot be priced like other lens products because they will be too expensive for many patients. In most cases, you will find that free-form lenses cost modestly more than traditional progressives, and considering the added features and benefits, easily justify their additional cost. One way to position free-form lenses to patients is to create a “good-better-

best” lens menu. In other words, create a tier system of lens prices for your progressives. The progressive that costs the least is your “good” progressive. Think of it as your basic value line progressive. This is probably an older progressive design that still provides good results. The “better” progressive is your middleof-the-road priced progressive and has additional features over the basic design. Your “best” progressive is your freeform progressive lens. This one offers the latest in technology and the most features and benefits. Since patients buy other products this way, they will understand the “good-better-best” pricing as long as you can explain the differences. With free-form lenses, this is easy to do. Be sure to offer your “best” lens to every patient. Let them decide if this is what they want. If not, you still have other choices that will meet their needs…but not with all the features and benefits of your “best” lens.

Can I verify free-form lenses with my manual or automated focimeter? This is a common question and one with a simple answer: Sure you can. No special instrumentation is needed, and you can read the powers of these lenses as you would a conventional PAL. Confusion sometimes arises with free-form lens power reading because

Varilux Physio 360° Varilux Physio 360°™ offers the ultimate in

effectiveness of the front design. Essilor

progressive precision. W.A.V.E.

has developed 360° Digital Surfacing,

Technology™: Wavefront Advanced Vision

which combines a patented calculation

Enhancement enhances both the front and

engine to optimize the design for every pre-

back of the lens through 360° Digital

scription, as well as a patented digital sur-

Surfacing™, which minimizes distortions

facing manufacturing process to produce

and preserves and enhances the

the back side surface of the lens.

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some designs compensate the prescription ordered for the patient due to the individualized measurements provided by the eyecare professional. Parameters such as vertex distance, pantoscopic and face form tilt have an effect on the prescription the patient experiences in his or her frame in its worn position. Especially in higher powers, the Rx delivered to the eye will appear different than the one written by the eye doctor. When this occurs, the laboratory that surfaced the lenses will provide the eyecare professional two prescriptions: the ordered prescription and one known as the compensated prescription. For example, with Pentax Internal Free-Form lenses, you will find two sets of values printed on the lens packaging. One set is the prescribed values for sphere, cylinder, axis, and add power. The second set contains the lensometer verification values after optimization by Pentax’s Retina Forward Design™ (this is the compensated Rx). These values provide the best image quality at the retina when the lenses are in the position of wear. Which one do you verify? The compensated one—it is the one that was compensated to reflect the effects of

design and fitting parameters. Use any manual or automated focimeter you wish to read the lens powers.

How do I determine which freeform lenses to recommend for a patient? Choosing a free-form lens is no more challenging than choosing any other progressive lens. The secret is to do a little research. The first thing to do is understand the needs of your patients. In other words, determine the needs your patients have, then go out and find a lens that satisfies those needs. For example, you may have patients that have a need for improved ground level viewing because you have a lot of golfers in your practice. In this case, consider using the Essilor DEFINITY™ progressive because of its Ground View Advantage™. Discuss the features, benefits, and performance characteristics of various lenses with lens manufacturers’ representatives or representatives from labs that supply these lenses. Next, read the printed information provided. It usually has good technical and clinical data, wearer trail results, prescribing and dispensing tips, and more.

Zeiss’ Gradal Individual Carl Zeiss Vision’s Gradal® Individual and Gradal Short i progressive lenses were among the first in the U.S. market produced through direct-to-surface processing. To make these lenses, Zeiss takes the particular factors that affect the manufacturing parameters and tailors them for each patient, thus offering a custom design for each individual.

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Once you feel you understand all the lenses, decide which one best matches your patients’ needs. This may be the easiest part of your analysis because some of these lenses adjust their design

Different free-form lenses offer different features and benefits. Essilor’s DEFINITY design incorporates Ground View Advantage™, which improves ground level viewing for patients who need it, such as golfers.

based on patient and frame parameters so they accommodate a far wider range of patients than traditional progressives. You also need to decide how this lens fits into your current selection of progressive lenses. In many cases, this will become your “best” progressive lens offering if you use the “good-betterbest” system of lens choices for patients. In other cases, you may wish to use it for selected patients like those with higher or more unusual prescriptions, strong cylinder, or previous progressive lens dropouts. Once you have decided to try the lens, conduct your own wearer trial. Select 10–12 patients that fit your selection criteria and use them as subjects. Dispense the lenses and follow-up with them in two weeks by calling and asking them questions about their wearing experiences. There is no better way to determine if a lens has merit than wearer trial results. If it works, it’s a winner; if it doesn’t, move on to something else.

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