straight talk about digital lenses -...

Straight Talk About Digital Lenses

Bringing you a greater understanding of the optical industry’s most talked about new technology.

Brought to you by these industry innovators:

Includes a free-form lens availability chart

DigitalLensSupp.qxd 10/13/06 4:45 PM

Shamir Creation™. Flat And Exact.

Shamir Creation was developed with patented Freeform Optics™ to provide resolution up to six times moreaccurate than standard cast PALs.

Shamir Creation features an extended base curve selection (up to 20 percent more than a leadingcompetitor) providing flatter, cosmetically superior lenses (up to 40 percent flatter).

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

Simulated Lower pixel resolution Simulated Higher pixel resolution

Shamir Creation and Freeform Optics are trademarks of Shamir Insight, Inc.

For more information please contact your ShamirAccount Executive at 877-514-8330 or yourReCreating Perfect Vision Partner Lab.

Comparatively, one can make ananalogy of Freeform Optics to thequality of a digital camera. Thehigher the pixel count, the higherthe degree of resolution itfacilitates and the more precisethe level of visual fine-tuning itpermits.

Simulation of 40% flatter lens.

CR

E-A

DS-

0606Shamir Creation is available in a wide range of materials from your Shamir Recreating Perfect Vision® partnering lab.

Project1 10/11/06 12:04 PM Page 1

DDigital lens processing, alsoreferred to as direct-to-surface

processing and, most prevalently, free-form, has been the talk of the opticalindustry since it first emerged in theU.S. market just a few short years ago.

It has resulted in numerous lensadvancements, and stands to be one ofthe most dynamic technological inno-vations in the manufacture of eyewear.For the first time, the wearer can actu-ally receive a corrective lens designedexpressly to accommodate his or herprescription, without the compromisespreviously necessitated by a conven-tional lens inventory built around anacceptable, though limited, number ofbase curves.

Most of the major lens manufacturershave at least one product on the market that employs direct-to-sur-face processing, and many more suchproducts are certain to follow. Infact, it is anticipated that direct-to-surface lenses will garner at least an8% market share by the end of thisdecade.

However, the rapid introduction ofthese products, many with differingtechnical and marketing claims, hascreated confusion among independentECPs, labs, and optical retailers.

We hope to clear up some of that con-fusion with this editorial presentationand leave you with a clearer idea ofthe features and benefits of this excit-ing, new technology. In these pages,we describe the free-form process andhow it works, explain how lensdesigners have addressed this new sys-tem of manufacture, and what it willmean for both lens casters and labs asthe technology proliferates.

We also discuss the significance offree-form to the practitioner and thepatient, how this may change the dis-pensing process, and how to adjust theculture of your practice or retail envi-ronment to address it.

This project would not have been pos-sible without the support of its spon-sors—Shamir Insight, Seiko OpticalProducts, Essilor and Carl ZeissVision—industry innovators all.

We hope you find “Straight Talk aboutDigital Lenses” to be useful and illu-minating. Thanks for reading…

—Jim Grootegoed,

Ed De Gennaro

Project Editors

PAGE 3

Why Discuss Digital Lenses?

Ed De Gennaro

Jim Grootegoed


FFreeform®. Digitally Computed PAL.Individual PAL. Direct to surface

technology. Digital Surfacing™. Direct-to-surface PAL. Vision First Design™.High Definition (HD) Technology.Personalized Progressive Lenses.

These are but a few terms all being usedto describe the same, new category of digi-tal lenses generically called free-form.

Just what are “free-form” lenses?Confused? Well, you should be. The evo-lution of the “Individually Measured,Computed and Manufactured ProgressiveAddition Lens Using ComputerPrograms To Run Three-Axis Generatorsand Polishers to Provide the Wearer Withan Optimized Lens Correction For AVisual Defect” is new and evolving. Theacronym, “IMCMPALUCPTRTAGPPWWOLCFAVD” to describe the processmight be a tad long and possibly difficultto remember, let alone explain to apatient. Therefore, the lens designers arecoining—and trademarking or register-ing—terms and phrases like those aboveto describe and differentiate the free-form process.

But, in reality, what is “IMCM-PALUCPTRTAGPPWWOLCFAVD”(free-form)?Basically, it consists of three separate buttotally dependent parts: A progressivelens design; a software program; and veryspecific processing equipment.

DesignFree-form lens design may be catego-rized into three basic types:1. “Optimized.” Free-form design can

be used to overcome optical aberrationsand mechanical limitations of traditionalsurfacing. 2. “Framitized.” The PAL designs aremodified to specific fitting, frame oradjustment characteristics.3. “Personalized.” The PAL designs arecreated specifically to the prescriptionand individual viewing habits of the user.

Each free-form design will includeitem one, above, and may, or may not,include item two and/or three.

Without going into painful detail, anyophthalmic lens with refractive powerplaced in front of the eye will causeaberrations away from the optical centerof the lens. Optical researchers haveidentified six aberrations (SphericalAberration, Coma, ObliqueAstigmatism, Chromatic Aberration,Curvature of Field, and Distortion), threeof which they consider capable of modi-fication to improve visual optics.Progressive addition lenses compoundthe problem inasmuch as they use asym-

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

HistoryThe design and manufacture of prescrip-tion ophthalmic lenses has really beenone of compromise between good optics,cosmetic considerations, machinery lim-itations and inventory concerns. When abase curve is chosen for a particularpower in order to minimize aberrations,the resulting lens is referred to as a “cor-rected curve” lens. The first attempt todesign a lens to minimize peripheralaberrations was the Punktal series of sin-gle vision lenses from Carl ZeissOptical, released in 1911, whichchanged the front base curve for everychange in power. Because hundreds ofbase curves were necessary (not a practi-cal option for a lab), American Opticalfollowed in 1921 with their Tillyer “cor-rected curve” series of lenses that wereflatter than “best form” designs for cos-

PAGE 4

I. Technology and Design

Seiko’s Internal ProgessivesSeiko 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

prescriptions and significantly expanded

PAL visual zones (distance, intermediate

and near).


metic reasons and standardized on sixbase curves for inventory concerns.Bausch & Lomb followed shortly withtheir Orthogon lenses.

Further, when surfacing compoundlenses using hard fixed power tools (laps)with a standard index of 1.53, and lensmaterials other than glass, the computedpowers will differ from the lap powers.As the power increases, the variance incalculated powers to lap powers increas-es.

For example, the computed cylinderpower may be -6.0626D. However, thelaps are either -6.0000D or -6.1250D.When this occurs, choices have to bemade to select one tool over the other. Ineither case, the resultant measured power

would be 0.07D off. When it came to multifocal lenses,

additional compromises had to be maderelative to intermediate and near visionplacements. Insets were averaged.Segment lengths for PALs were also amatter of the manufacturer’s design rang-ing initially from about 22mm to 24mmin length and now modified to be asshort as 13mm.

Progressive lenses caused additionaldistortions because the powers fordistance, intermediate and near werepushed all over the front surface of the lens.

To summarize, the lenses we havebeen 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 notnecessarily that of the patient’s desire;

• use an arbitrary reading inset possi-bly adjusted for add power but not forPD.

We, as an industry, have been provid-ing compromised optics to our patients!

Free-form lenses may be designed tocorrect, as much as is optically possible,these compromises resulting in signifi-cantly improved vision. The software cancalculate the “perfect” curve(s) andcylinder cross-curve(s) to 1/100th of adiopter (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:

PAGE 5


length based upon the fitting height andframe “B” measurements, and the nearvision inset based upon add power andPD. The free-form machinery availabletoday can produce those curves.

What about the software?The key to the new “free-form” PALlenses is the software that calculates thecurves for the individual designs anddrives the machinery to manufacture thelenses. The process starts with a theoreti-cal design model, not unlike conventionalPALs, using the front surface, the backsurface or a combination of the surfaces.The optimal curves are calculated forevery possible prescribed power at thou-sands of points on the lens surface result-ing in a “point file” describing, in mathe-matical terms, the surface of the lens.Inasmuch as various lens materials allhave different indexes of refraction, theoptimal curves must be calculated forevery material, too. This information isultimately used to drive the productiongenerator and polisher used to manufac-ture the lens.

We have currently (September 2006)identified fifteen separate free-formdesigns (see Availability Chart, page 7),most from traditional lens manufacturers.Some designs will place both the pro-gressive design and the power parameterson the backside. Other designs use boththe front and back surface for powers andprogressive designs. Some require a dis-tance measurement as well to approxi-mate the distance from the back surfaceof the lens to the front surface of thecornea—most do not. Others require theanalysis and measurement of how thepatient uses and moves his eyes underreading conditions as part of the lens cal-culations. Whatever the requirements, theresultant lens can be significantly moreaccurate than any lens currently available

on the market and provide the user with anew level of clarity.

What about the machinery neces-sary for free-form lenses?The calculations necessary for optimallens designs date back to the 1800s butwere limited by practical concerns, suchas stocking inventory, and real barriers,including the processing machinery. Thetraditional surfacing machinery used to“generate” a curve was designed to bereliable, robust and reasonably accurateas the final curves were “fined” in usinghard tools (laps). The resultant curveswere always that of the tool.

Precision tool making in other indus-tries spawned the development ofComputer 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 indus-tries are huge users of this technology,requiring extreme precision down to thenanometer level and extreme reliabilityto run 24/7. (One inch = 24,400,000nanometers). This technology became thebasis for free-form machines used tomanufacture free-form lenses.

In reality, CNC machinery can manu-facture just about any shape imaginable;but it can only do this when its softwareproperly drives the machines to constructa precision lens—a spherical, cylindrical,aspheric and individually designed free-form PAL.

The key to today’s free-form processis the ability to deliver a near finishedquality surface off the cutting generator.This is typically done by using two tools:a roughing tool to crib the lens and togenerate the surface curves to a reason-able quality, then a single-point diamondtool to skim the surface of the lens leav-ing a finish that can be polished using a

CNC polisher and a soft, rotating toolalso driven by three (or more) axis tech-nology and the operating software. Powertolerances of less than one-one hundredth(1/100) of a diopter are possible. The sur-face smoothness necessary off the gener-ator for polishing is 1 micron…1/25,400th of an inch!

State of the UnionMost lens manufacturers are already pro-viding their patented designs throughtheir own in-house manufacturing loca-tions with millions of satisfied patientsalready wearing free-form lenses world-wide. The software engineers have alsoworked closely with the CNC machinemanufacturers to ensure process transfer-ence and viability. Some free-formdesigners prefer optimizing their designsto a specific equipment platform whileothers have validated their process with anumber of equipment providers.

Many of the designs are currentlyavailable to eye care professionalsthrough their local laboratories, whichwill order the uncut lens from the lensmanufacturer and provide the finishingservices. Many of the holders of the free-form software are currently offering theircalculation and machine software tomanufacturing laboratories worldwide.The interest among the laboratories isextremely high, limited only by the costof the investment (a minimum of$400,000 to well over $1 million). Mostof the experts are predicting that free-form PAL lenses will constitute between8% and 20% of the market within fiveyears, certainly adequate to justify theinvestment.


(*) SunSensors Polycarb 1.60 1.67Manufacturer Brand 1.50 Transitions Polarized Trivex 1.56 Polycarb Transitions 1.60 Transitions 1.67 Transitions 1.70 1.74

Carl Zeiss Vision AO Easy HD @ @SOLAOne HD @ @Gradal Individual @ @Gradal Short i @

Essilor DEFINITY x x x xDEFINITY Short x x x xVarilux Ipseo @ @ @ @ @ @Variux Physio 360º @ @ (1) @ @ @ @ (1)

Hoya Hoyalux iD @ @Indo EyeMADE x(1.523) X XSeiko/Pentax Exceed Internal @ @

Succeed Internal x (2) (2) (2) x xPentax Perfas @

Shamir Autograph x x x x x x x x xSignet Armorlite KODAK Unique @ @ @ @ @ @ @ @ @ @

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.

Minimum CombinedFitting Free-form Lens Power Range Power

Manufacturer Brand Height Design Material (**) Sphere Cylinder Limitation Add CommentsCarl Zeiss Vision AO Easy HD 18mm Back 1.67 & +8.00 to -12.00D -4.00D +1.00 to +3.50D

SOLAOne HD 18mm Back 1.67 Trans +8.00 to -12.00D -4.00D +1.00 to +3.50DGradal Individual 18mm Back; 1.60 +10.00 to -10.00D -6.00D +0.75 to +3.50D Standard fitting information acceptable but

Front in 1.67 +6.50 to -17.00D -6.00D +0.75 to +3.00D additional specifications as vertex distance,High frame wrap and panto angle using their Eye-

Gradal Short i 15mm Powers 1.60 +6.00 to -6.00D -6.00D +0.75 to +3.00D Terminal will result in a more exact lens calc.Essilor DEFINITY 18mm PAL front 1.50 +6.00 to -10.00D -4.00D +1.00 to +3.00D Features a 4th ground level viewing zone

DEFINITY Short 15mm Add split Trans +6.00 to -10.00D -4.00D +1.00 to +3.00D named “Ground View Advantage.”Power back Poly +4.00 to -5.00D -2.00D +1.00 to +3.00D

1.60 +8.00 to -12.00D -4.00D +1.00 to +3.00DVarilux Ipseo 14, 16, 18mm Back See above +6.00 to -10.00D -4.00D +0.75 to +3.50D Requires use of the Varilux VisionPrint System.Variux Physio 360º 17mm PAL front See above +9.00 to -12.00D -4.00D +0.75 to +4.00D

Power backHoya Hoyalux iD 14, 16, 18mm PAL and 1.67, 1.70 +6.00 to -10.00D -4.00D +0.75 to +3.50D

power splitIndo EyeMADE 16mm Back 1.523 +6.00 to -6.00D -4.00D +0.75 to +3.50D Requires information from testing head/eye

1.60 +7.00 to -12.00D -4.00D +0.75 to +3.50D movements with their Visual Map.1.67 +6.00 to -13.00D -4.00D +0.75 to +3.50D

Seiko/Pentax Exceed Internal 14, 16, 18mm Back See above +6.00 to -10.00D -4.00D -10.00 +0.50 to +3.50DSucceed Internal 17, 19mm Back 1.50 +4.00 to -5.00D -4.00D -7.00 +0.50 to +3.50D

Poly +5.00 to -7.00D -4.00D -8.00 +0.50 to +3.50D1.67 +6.50 to -10.50D -4.00D -10.50 +0.50 to +3.50D

Pentax Perfas 12, 14, 16mm Back 1.67 +6.00 to -10.00D -5.00D -10.00 +0.50 to +3.50DShamir Autograph 16, 19mm Back 1.50 +4.00 to -8.50D -4.00D +0.75 to +3.50D

16, 19mm Back Trans +4.00 to -8.50D -4.00D +0.75 to +3.50D16, 19mm Back Polarized +4.00 to -7.00D -4.00D +0.75 to +3.50D

19mm Back Poly +6.00 to -10.00D -4.00D +0.75 to +3.50D19mm Back Poly Trans +6.00 to -10.00D -4.00D +0.75 to +3.50D

16, 19mm Back 1.60 +6.00 to -10.00D -4.00D +0.75 to +3.50D16, 19mm Back 1.60 Trans +6.00 to -10.00D -4.00D +0.75 to +3.50D

19mm Back 1.67 +6.00 to -12.50D -4.00D +0.75 to +3.50D19mm Back 1.67 Trans +6.00 to -12.50D -4.00D +0.75 to +3.50D

Signet Armorlite KODAK Unique 13mm Back 1.50 +6.50 to -9.50D -4.00D +1.00 to +3.00D Frame “B” dimension required.Trans +4.75 to -10.00D -4.00D +1.00 to +3.00D

Polarized +4.75 to -8.75D -4.00D +1.00 to +3.00DTrivex +4.75 to -10.00D -4.00D +1.00 to +3.00D

SunSens 1.56 +5.25 to -10.00D -4.00D +1.00 to +3.00DPoly +4.25 to -10.00D -4.00D +1.00 to +3.00D

Poly Trans +4.25 to -10.00D -4.00D +1.00 to +3.00D1.60 +8.00 to -10.00D -4.00D +1.00 to +3.00D

1.60 Trans +6.25 to -10.00D -4.00D +1.00 to +3.00D1.67 +7.75 to -10.00D -4.00D +1.00 to +3.00D

(**) 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.

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


F

PAGE 8

Free-form progressive lenses have agood number of advantages. Giving

patients the right messages in the rightway will enhance their understanding ofthe value these lenses provide while, atthe same time, enhancing your profes-sional abilities and your bottom line.

How do I explain the differencesbetween these lenses and standardprogressives in simple terms?As with any new technology, there is alearning curve for both the eyecare practi-tioner and the patient. Trying to conveyconfusing descriptions of how point filesand free-form processing equipment cre-ate these lenses will only serve to confusethe patient. Instead, a simple, logicalexplanation is the best approach. Yourgoal should be to give them enough infor-mation to make them feel comfortablethat they have received good value fortheir money.

There is wide variation in the featuresand benefits this category of lenses pro-vides, but as a group, free-form lensesmaximize the design of the lens a patientbuys. In other words, the free-formprocess brings out the potential in a lensdesign which can help it deliver clearer,sharper vision with wider fields of view.A number of them also offer an individu-alized prescription, which means thepatient gets a highly accurate prescription.

The best explanation of free-formlenses is that they represent the latestfrontier in lens technology. With all theemphasis on advanced technology thesedays from things like iPods to cellphones, just about everyone wants toknow they are purchasing the latest and

greatest when they buy something.Progressive lenses are surely part of thattrend. Most patients will be completelysatisfied with this explanation.

Before you can tackle the job ofexplaining free-form lenses to yourpatients, you need to understand the fea-tures and benefits of the process and thespecific features and benefits of the lensproduct you’re recommending. Whileyour explanation to the patient should besimple, it must be accurate. Your lab orlens manufacturer’s representative canhelp you with this information.

Will the patient appreciate the dis-tinctions between these new lensesand conventional ones?In a word, yes. Well-designed, well-measured, and well-fitted free-form lens-es can provide enhanced results overconventionally designed and producedprogressive lenses. Will the results bedramatic for a -0.50 -0.75 x 180 wearer?

Perhaps not, but many eyecare profes-sionals report that patients who havetried on free-form lenses for the firsttime have a startled reaction becausetheir vision is so good. This is becausethe free-form process aids its progressivelens design to deliver crisper, sharper,bolder vision. For wearers, this meansthey receive advanced technology lensesthat enhance vision over conventionallydesigned and processed progressives.First-time progressive lens wearers willappreciate this a great deal because itmeans they will spend little time adapt-ing to the lens.

Another reason free-form lenses pro-vide this reaction is because they are pro-duced using individualized curves deter-mined by the patient’s prescription.

Some free-form lenses like the CarlZeiss Vision Gradal® Individual,Varilux® Ipseo™, and Seiko SucceedInternal Free-Form™ and ExceedInternal Free-Form™ are customized for

II. The Patient

Shamir AutographPart 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 back-

surface design.


No two fingerprints or snowflakes are ever

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

Zeiss developed breakthrough technology that

creates a premium progressive lens for each

individual patient. Gradal Individual allows you to

incorporate new measurements for truly

individualized lenses. Plus, two channel lengths,

with fitting heights starting at 15mm, enable you to

deliver perfect vision in both traditional and smaller

style frames. The result: individualized comfort and

patient satisfaction. For more information on

Gradal Individual and Gradal Short i, call

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

No Two Are Ever AlikeGradal® Individual and Gradal® Short

Project1 10/11/06 12:05 PM Page 1

D

the wearer. Based on the dimensions ofthe frame, these lenses adjust the lens’design to customize and optimize it. Forexample, Individual has a fitting lengththat varies from 14mm to 20mm. Ipseouses three fitting heights in 2mm incre-ments—14mm, 16mm, and 18mm.Seiko’s Exceed has 14mm, 16mm, or18mm minimum heights while itsSucceed uses 17mm or 19mm. Thisdesign flexibility basically avoids thequestion of whether the lens is a long orshort corridor lens. The design compen-sates the corridor and the optics of thelens simultaneously. Customizing thecorridor length gives the patient exactlywhat he or she needs without going toolong or too short.

Experienced PAL patients may findthat they no longer need to move theirheads around to find the different visualfields; they are exactly where theyshould be. This means they can just droptheir eyes instead of moving their headsearching for “the right spot” to view anobject.

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

can do. Think of it as a one person, onepair wearer trial with you as the subject.Make notes of the characteristics youfind most appealing so you’ll be able toexplain them to patients later. No onewill do a better job of explaining thebenefits of a pair of free-form lensesthan a satisfied eyecare professionalwearer.

The other reason is that your patientsexpect you to be the eyewear expert inyour office. If you’re a presbyope, manyof them will ask you what progressivelenses you wear. Being able to say tothem that you wear the newest and mostadvanced style of lenses is invaluable.You can even take yours off and say,“See, these are my free-form XYZ lens-es.” Use them as a demo as you explainthe advanced features of the lenses.

How can I justify the cost differen-tial to the patient?For most patients, cost is not the issuewhen buying eyewear; the issue is receiv-ing value for the money they spend. Thisis especially true of lenses when patientsview them as the medically necessaryportion of their eyewear. They might cutback a bit on their frame, but the lensesare the main reason they obtain eyewear.

The more features and benefits a

product provides; the more value it deliv-ers. The more value it delivers, the morethe patient will want to buy it. The key injustifying the cost of free-form lenses isto detail the features and benefits of themto the patient. With each one mentionedand explained, the value of the lensesbecomes greater and makes the lensesmore appealing.

Do lens add-ons help the lensesperform better?Good quality lens add-ons can enhancefree-form lenses just like they do anyother lenses. Of course, the most obviousone is an oleophobic/hydrophobic anti-reflective treatment. In fact, some free-form lenses like Varilux® Physio™360°™, Signet Armorlite’s KODAKUnique, and Seiko’s Exceed InternalFree-Form (and other free-form lenses)are only available with anti-reflectivetreatment. Since you are already givingyour patient advanced technologydesigned and processed free-form lenses,why would you want to have themannoyed by distracting, troublesome andsight-reducing surface reflections? Thisis especially true of free-form lensesmade with high-index lens materials.

Do I need to refract the patientdifferently for free-form lenses?

No, there is no difference in the refractingprocess for these lenses. Standard refract-ing equipment and other ophthalmicinstrumentation should be used. Ofcourse, you will want to ask questions

about the patient’s lifestyle, viewingneeds and viewing distances, special con-cerns like not wanting to drop their eyestoo far into the lens when doing nearwork, and other questions you would nor-mally ask before performing a refraction.The more accurate and personalized the

prescription is for the patient, the higherlevel of satisfaction he will have with hisfree-form lenses.

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

III. Prescribing and Dispensing


than the usual measures you currently provide for traditionalprogressive lenses—the patient’s monocular PD and monocularsegment height along with the frame data and other eyewearrelated information (e.g. material, tint, etc.). Some lenses like theCarl Zeiss Vision Gradal® Individual allow you to supply addi-tional measurements for more precise customization, includingvertex distance, pantoscopic tilt and face form (also known as“wrap” these days) tilt. Varilux® Ipseo™ and Indo’sEyeMADE® offer additional instrumentation to measure howthe patient uses his or her eyes. This information is then incor-porated with the prescription into the design. Essilor’s DEFINI-TY™ asks ECPs to pick one of eight standard frame shapes andto include this information on the patient’s prescription.

While all surfacing laboratories will want to know theframe’s A, B, ED and DBL measurements to determine if thelens will cut out in the frame, some will use these data to cus-tomize the design for the wearer. The Varilux Ipseo and theSignet Armorlite KODAK Unique are good examples of this.Based on the fitting height you supply, the lens’ corridor lengthwill be adjusted so that it is optimized for the patient.

Remember that one of the biggest contributors to progres-sive lens failures is inaccurate measurements, especially seg-ment heights and monocular PDs. As with any progressiveaddition lens, use a corneal reflex pupilometer to obtainmonocular PDs. When using a ruler to take segment heights, besure to pre-adjust the frame as if you were dispensing the eye-wear. This is particularly important for those lenses that requirepantoscopic tilt, face form tilt (wrap) and vertex distance meas-urements. Sit in front of the patient so that you are on the sameeye level. This avoids parallax and inaccuracies.

Once you begin to take the fitting height measurements, donot move your head, just your ruler hand from eye to eye. Ifyou move your head, you will have broken your alignment tothe patient, creating the potential for inconsistent measure-ments. Take fitting height readings at least twice to ensure theyare the same. This also helps to avoid errors.

Do I need any special equipment to measure thepatient for free-form lenses?In most cases, you do not need any additional instrumentation orequipment other than the usual complement of measuringdevices, such a corneal reflex pupilometer and a PD ruler.

For Varilux Ipseo, a special eye tracking device called theVisionPrint System® is used to measure the patient’s uniquehead and eye movements. These data are used to personalizethe lens for the patient’s unique viewing habits during manufac-

a. I have dispensed free-form progressives and feel they aresuperior to conventional PALs.

b. I have dispensed free-formprogressives and feel they are nobetter than conventional PALs.

c. I have not dispensedfree-form progressivesbut I plan to do so soon.

d. I have not dispensedfree-form progressivesand do not plan to do so.

e. I do not prescribe ordispense lenses.

A32%

E34%

C34%

Total respondents: 56

ECP Perceptions ofFree-Form Lenses

1. Which statement best describes you?

2. What do you perceive to be the majorbenefit of free form lenses?

a. More accurate Rx for thepatient.

b. Greater profit margin fordispensers

c. A solution for high powered ordifficult prescriptions.

d. Don’t know.


A87%

C 9%D 4%

3. When you hear the term “free formprocessing,” what do you think it means?

a. A new way to makeprogressive lenses.

b. A new way to makeall lenses.

c. Computer lens designing.d. Taking slabs of plastic and

cutting lenses out of them.e. All of the above.


E68%

A 14%

B 9%C 9%

These results were generated via audience surveyduring the webinar presentation of “Straight TalkAbout Digital Lenses,” 9/28/06.


PAGE 12

ture. If you use this lens, you will wantthis instrument, which is availablethrough Essilor.

Some free-form lenses require pantoscopictilt and vertex distance measurements. Youmay also be asked for a face form tilt meas-urement. A distometer can be used tomeasure vertex distance, and some ECPsuse a PD ruler for this measurement. Thereare instruments designed to measure panto-scopic tilt on the market. Face form tiltcan be estimated using a chart-like device.

Manufacturers are coming onto themarket with electronic measuring devicesthat take patient fitting measurementsautomatically. For example, the Carl ZeissVision’s Eye Terminal measures monocu-lar fitting heights, monocular PDs, panto-scopic tilt, face form tilt, and vertex dis-tance, all with electronic accuracy.

Will recommending free-form lensesadd to my chair time?No, prescribing free-form lenses will notadd any time to your normal examinationroutine if you are already performing apatient interview before you refract. Forsome lenses, a couple of additional min-utes may be added to the dispensing rou-tine for one or more additional measure-ments needed.

Are free-form lenses suitable for allpatients?Yes, free-form lenses are effective fornearly every presbyopic patient, not justbecause of their advanced free-form pro-cessing, but because, in most cases, man-ufacturers are developing advanceddesigns to use with free-form processingtechniques. This means that patientsreceive the latest in lens design and tech-nology along with the most accuratemethod for processing these lenses.

One major advantage of free-formlenses is their ability to be customizedfor the patient’s individual frame and Rx.This kind of optics benefits just abouteveryone. It is especially suitable forthose with strong prescriptions, thosewho have had poor results with prior pro-gressive lens designs and those with highcylinder in the prescription. Anyone whowants the best optical performance avail-able in today’s progressive lenses is asuitable candidate for customized free-form lenses. Those who want the latestadvancements in lens technology are alsosuitable candidates for free-form lenses.

I’ve heard that free-form lenses maybe too complicated for staff to dis-pense. Is this true?

Free-form lenses are no more difficult torecommend, demonstrate, measure, andorder than any other progressive additionlens. As with any progressive lens, gooddispensing procedures are called for.Keep the vertex distance as close to theeyes as possible while avoiding the eyelashes from touching the back surface ofthe lenses. Be sure to include adequatepantoscopic tilt and use face form tilt toposition the lenses properly in front ofthe eyes.

Some free-form lens designs requireadditional measurements, but these canbe learned, practiced, and perfected inless than 30 minutes. Even staff memberswho are not certified or licensed dispens-ing personnel will not have difficultyworking with these lenses once they havelearned the fundamentals. This knowl-edge and training can be obtained inprinted form from lens manufacturers,professional journals, and continuingeducation articles. Hands-on training canbe provided by optical laboratories, lenscompanies, and co-workers. In short,free-form lenses are just as easy to workwith as traditional progressive lenses.

IV. Ordering, Fees, and Other Questions

DDo I obtain free-form lenses theway I do other lens products?

Yes, simply call an authorized surfacinglab or, in some cases, the lens supplierfor the lens brand you wish to obtain,and they will handle your order.Remember that some lenses require

additional measurements over the stan-dard monocular PD and segment heightused by conventional progressive lenses.Not sending these in at the time ofordering will only delay processing.

Some lenses are also only availablewith certain treatments included. For

instance, Varilux® Physio™ 360°™ andVarilux® Physio™ are sold with CrizalAlizé with Clear Guard™, Essilor’s top-of-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


on it. SOLAOne™ HD and AO EasyHD from Carl Zeiss Vision both comeonly with Teflon® Clear Coat whiletheir Gradal® Individual and Gradal®Short i are produced with the ZeissCarat® Advantage AR coating. Be sureto know your product’s availabilitybefore you recommend it to a patient toavoid disappointment and dissatisfac-tion. A few quick mouse clicks on amanufacturer’s or lab’s Web site or a fastphone call will usually get you theanswers you need in minutes.

Should the lab finish the lenses orcan I do this?This is a decision you’ll have to make.Nearly all of the lenses are availableuncut (so you can cut, edge, and finishthem). While a good number of opticaloffices have finishing capabilities, mostlaboratories will be pleased to fabricateyour complete order including surfacingthe lenses, cutting and edging, drilling,mounting, tinting, and hard coatingthem. Some of these lenses can only beordered with AR treatments. For thosethat are available without it, your labwill arrange to have that done for you.Of course, some laboratories strictly pro-duce uncut lenses for you to edge.

If you’re comfortable edging and fin-ishing your own lenses, be sure to askyour lab about this option when you

order the lenses. Be aware that some lenses are only

available directly from the manufactureritself (not through authorized labs). Forexample, the Pentax Perfas Internal Free-Form is produced by Seiko/Pentax andsold uncut (you have to do the finishinglab work on it).

Should I set my fees for these lensesthe same way I do now for otherlenses?How much you charge for your productsand services is a very individual choice.There is no magic formula to follow thatworks for every office and every patient.If you have a fee formula for lenses thatyou have successfully followed, by allmeans, continue to use it with free-formlenses.

Some eyecare professionals have theimpression that free-form lenses aremuch more expensive than traditionalprogressives at the wholesale level andtherefore cannot be priced like other lensproducts because they will be too expen-sive for many patients. In most cases,you will find that free-form lenses costmodestly more than traditional progres-sives, and considering the added featuresand benefits, easily justify their addition-al cost.

One way to position free-form lensesto patients is to create a “good-better-

best” lens menu. In other words, create atier system of lens prices for your pro-gressives. The progressive that costs theleast is your “good” progressive. Thinkof it as your basic value line progressive.This is probably an older progressivedesign that still provides good results.The “better” progressive is your middle-of-the-road priced progressive and hasadditional features over the basic design.Your “best” progressive is your free-form progressive lens. This one offersthe latest in technology and the mostfeatures and benefits. Since patients buyother products this way, they will under-stand the “good-better-best” pricing aslong as you can explain the differences.With free-form lenses, this is easy to do.

Be sure to offer your “best” lens toevery patient. Let them decide if this iswhat they want. If not, you still haveother choices that will meet theirneeds…but not with all the features andbenefits of your “best” lens.

Can I verify free-form lenses withmy manual or automated focimeter?This is a common question and one witha simple answer: Sure you can. No spe-cial instrumentation is needed, and youcan read the powers of these lenses asyou would a conventional PAL.

Confusion sometimes arises withfree-form lens power reading because

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

progressive precision. W.A.V.E.

Technology™: Wavefront Advanced Vision

Enhancement enhances both the front and

back of the lens through 360° Digital

Surfacing™, which minimizes distortions

and preserves and enhances the

effectiveness of the front design. Essilor

has developed 360° Digital Surfacing,

which combines a patented calculation

engine to optimize the design for every pre-

scription, as well as a patented digital sur-

facing manufacturing process to produce

the back side surface of the lens.


PAGE 14

some designs compensate the prescrip-tion ordered for the patient due to theindividualized measurements providedby the eyecare professional. Parameterssuch as vertex distance, pantoscopic andface form tilt have an effect on the pre-scription the patient experiences in his orher frame in its worn position.Especially in higher powers, the Rxdelivered to the eye will appear differentthan the one written by the eye doctor.When this occurs, the laboratory thatsurfaced the lenses will provide the eye-care professional two prescriptions: theordered prescription and one known asthe compensated prescription.

For example, with Pentax InternalFree-Form lenses, you will find two setsof values printed on the lens packaging.One set is the prescribed values forsphere, cylinder, axis, and add power.The second set contains the lensometerverification values after optimization byPentax’s Retina Forward Design™ (thisis the compensated Rx). These valuesprovide the best image quality at theretina when the lenses are in the posi-tion of wear.

Which one do you verify? The com-pensated one—it is the one that wascompensated to reflect the effects of

design and fitting parameters. Use anymanual or automated focimeter you wishto read the lens powers.

How do I determine which free-form lenses to recommend for apatient?Choosing a free-form lens is no morechallenging than choosing any other pro-gressive lens. The secret is to do a littleresearch.

The first thing to do is understand theneeds of your patients. In other words,determine the needs your patients have,then go out and find a lens that satisfiesthose needs. For example, you may havepatients that have a need for improvedground level viewing because you have alot of golfers in your practice. In thiscase, consider using the Essilor DEFINI-TY™ progressive because of its GroundView Advantage™.

Discuss the features, benefits, andperformance characteristics of variouslenses with lens manufacturers’ repre-sentatives or representatives from labsthat supply these lenses. Next, read theprinted information provided. It usuallyhas good technical and clinical data,wearer trail results, prescribing and dis-pensing tips, and more.

Once you feel you understand all thelenses, decide which one best matchesyour patients’ needs. This may be theeasiest part of your analysis becausesome of these lenses adjust their design

based on patient and frame parametersso they accommodate a far wider rangeof patients than traditional progressives.

You also need to decide how this lensfits into your current selection of pro-gressive lenses. In many cases, this willbecome your “best” progressive lensoffering if you use the “good-better-best” system of lens choices for patients.In other cases, you may wish to use itfor selected patients like those withhigher or more unusual prescriptions,strong cylinder, or previous progressivelens dropouts.

Once you have decided to try thelens, conduct your own wearer trial.Select 10–12 patients that fit your selec-tion criteria and use them as subjects.Dispense the lenses and follow-up withthem in two weeks by calling and askingthem questions about their wearingexperiences. There is no better way todetermine if a lens has merit than wearertrial results. If it works, it’s a winner; if itdoesn’t, move on to something else.

Zeiss’ Gradal IndividualCarl 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 pro-

cessing. To make these lenses, Zeiss

takes the particular factors that affect

the manufacturing parameters and tai-

lors them for each patient, thus offering

a custom design for each individual.

Different free-form lenses offer different featuresand benefits. Essilor’s DEFINITY design incorpo-rates Ground View Advantage™, which improvesground level viewing for patients who need it,such as golfers.


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