digital lens zeiss
TRANSCRIPT
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Straight Talk About
Digital LensesBringing you a greater understanding of the opticalindustrys most talked about new technology.
Brought to you by these industry innovators:
Includes a free-form
lens availability chart
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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).
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
Shamir Creation and Freeform Optics are trademarks of Shamir Insight, Inc.
For more information please contact your Shamir
Account Executive at 877-514-8330 or your
ReCreat ing Perfect Vision Partner Lab.
Comparatively, one can make an
analogy of Freeform Optics to the
quality of a digital camera. The
higher the pixel count, the higherthe degree of resolution it
facilitates and the more precise
the level of visual fine-tuning it
permits.
Simulation of 40% flatter lens.
CRE-ADS-0606
Shamir Creation is available in a wide range of materials from your Shamir Recreating Perfect Vision partnering lab.
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D
Digital lens processing, alsoreferred to as direct-to-surfaceprocessing and, most prevalently, free-
form, has been the talk of the optical
industry since it first emerged in the
U.S. market just a few short years ago.
It has resulted in numerous lens
advancements, 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 designed
expressly to accommodate his or her
prescription, without the compromises
previously necessitated by a conven-
tional 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-sur-
face processing, and many more such
products are certain to follow. In
fact, it is anticipated that direct-to-
surface lenses will garner at least an
8% market share by the end of this
decade.
However, the rapid introduction ofthese 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 con-
fusion with this editorial presentation
and leave you with a clearer idea of
the features and benefits of this excit-
ing, new technology. In these pages,
we describe the free-form process and
how it works, explain how lens
designers have addressed this new sys-
tem of manufacture, and what it willmean 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 dis-
pensing process, and how to adjust the
culture of your practice or retail envi-
ronment to address it.
This project would not have been pos-sible without the support of its spon-
sorsShamir Insight, Seiko Optical
Products, Essilor and Carl Zeiss
Visionindustry innovators all.
We hope you find Straight Talk about
Digital Lenses to be useful and illu-
minating. Thanks for reading
Jim Grootegoed,
Ed De GennaroProject Editors
Why Discuss Digital Lenses?
Ed De Gennaro
Jim Grootegoed
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FFreeform. Digitally Computed PAL.Individual PAL. Direct to surfacetechnology. Digital Surfacing. Direct-
to-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 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 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 difficultto remember, let alone explain to a
patient. Therefore, the lens designers are
coiningand trademarking or register-
ingterms and phrases like those above
to 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 progressive
lens design; a software program; and very
specific processing equipment.
Design
Free-form lens design may be catego-
rized into three basic types:
1. Optimized. Free-form design can
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 modi-fication 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 prescrip
tion ophthalmic lenses has really been
one of compromise between good optic
cosmetic considerations, machinery lim
itations and inventory concerns. When
base curve is chosen for a particularpower in order to minimize aberrations
the resulting lens is referred to as a co
rected curve lens. The first attempt to
design a lens to minimize peripheral
aberrations was the Punktal series of sin
gle 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 pract
cal option for a lab), American Opticalfollowed in 1921 with their Tillyer cor
rected curve series of lenses that were
flatter than best form designs for cos
PAGE 4
I. Technology and Design
Seikos Internal Progessives
Seiko is the patent holder of the worlds
first internal progressive. Seikos internal
progressives 3-dimensionally fuse a
patients 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).
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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 compoundlenses 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 increas-
es.
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 bemade 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 manufacturers design rang-
ing 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 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 nonecessarily that of the patients desire;
use an arbitrary reading inset poss
bly adjusted for add power but not for
PD.
We, as an industry, have been provid-
ing compromised optics to our patients!
Free-form lenses may be designed to
correct, as much as is optically possible
these compromises resulting in signifi-
cantly improved vision. The software ca
calculate the perfect curve(s) andcylinder 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?
Its 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.
Dont be left in the dark about free-form!
This event is sponsored by:
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PAGE 6
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 theoreti-
cal design model, not unlike conventional
PALs, using the front surface, the back
surface 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 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 manufac-
ture 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 pro-
gressive 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 dis-
tance measurement as well to approxi-
mate the distance from the back surfaceof the lens to the front surface of the
corneamost 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 cal-
culations. Whatever the requirements, the
resultant lens can be significantly more
accurate than any lens currently available
on the market and provide the user with a
new level of clarity.
What about the machinery neces-
sary 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 indus-
tries 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 indus-
tries are huge users of this technology,
requiring extreme precision down to the
nanometer level and extreme reliability
to run 24/7. (One inch = 24,400,000nanometers). This technology became the
basis for free-form machines used to
manufacture free-form lenses.
In reality, CNC machinery can manu-
facture just about any shape imaginable;
but it can only do this when its software
properly drives the machines to construct
a precision lensa spherical, cylindrical,
aspheric and individually designed free-
form PAL.
The key to todays free-form processis 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 reason-
able quality, then a single-point diamond
tool to skim the surface of the lens leav-
ing a finish that can be polished using a
CNC polisher and a soft, rotating tool
also driven by three (or more) axis tech-
nology and the operating software. Pow
tolerances of less than one-one hundred
(1/100) of a diopter are possible. The suface smoothness necessary off the gener
ator for polishing is
1 micron1/25,400th of an inch!
State of the Union
Most lens manufacturers are already pro
viding their patented designs through
their own in-house manufacturing loca-
tions with millions of satisfied patients
already wearing free-form lenses world-
wide. The software engineers have alsoworked closely with the CNC machine
manufacturers to ensure process transfe
ence and viability. Some free-form
designers prefer optimizing their design
to a specific equipment platform while
others have validated their process with
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 lensmanufacturer and provide the finishing
services. Many of the holders of the free
form software are currently offering the
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 free-
form PAL lenses will constitute between8% and 20% of the market within five
years, certainly adequate to justify the
investment.
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(*) SunSensors Polycarb 1.60 1.67Manufacturer Brand 1.50 Transit ions Polar ized Trivex 1.56 Polycarb Transitions 1.60 Transit ions 1.67 Transit ions 1 .70 1
Carl Zeiss Vision AO Easy HD @ @
SOLAOne HD @ @
Gradal Individual @ @
Gradal Shorti @
Essilor DEFINITY x x x x
DEFINITY Short x x x x
Varilux Ipseo @ @ @ @ @ @
Variux Physio 360 @ @ (1) @ @ @ @ (
Hoya HoyaluxiD @ @
Indo EyeMADE x(1.523) X X
Seiko/Pentax Exceed Internal @ @
Succeed Internal x (2) (2) (2) x x
Pentax Perfas @
Shamir Autograph x x x x x x x x x
Signet 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 Comments
Carl 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 +3.50D
Gradal 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 Shorti 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 +3.00D
Varilux 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 360 17mm PAL front See above +9.00 to -12.00D -4.00D +0.75 to +4.00D
Power back
Hoya HoyaluxiD 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 +3.50D
Succeed 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 +3.50D
1.67 +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 +3.50D
Shamir 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 +3.50D
16, 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 +3.50D
19mm 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 +3.50D
16, 19mm Back 1.60 Trans +6.00 to -10.00D -4.00D +0.75 to +3.50D19mm Back 1.67 +6.00 to -12.50D -4.00D +0.75 to +3.50D
19mm 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 +3.00D
Trivex +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 +3.00D
Poly +4.25 to -10.00D -4.00D +1.00 to +3.00D
Poly Trans +4.25 to -10.00D -4.00D +1.00 to +3.00D
1.60 +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 +3.00D
1.67 +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.)
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PAGE 8
F
PAGE 8
Free-form progressive lenses have agood number of advantages. Givingpatients the right messages in the right
way will enhance their understanding of
the value these lenses provide while, at
the same time, enhancing your profes-
sional abilities and your bottom line.
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 practi-
tioner and the patient. Trying to convey
confusing descriptions of how point files
and free-form processing equipment cre-
ate 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 infor-
mation to make them feel comfortable
that they have received good value fortheir money.
There is wide variation in the features
and benefits this category of lenses pro-
vides, 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 individu-
alized prescription, which means thepatient 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
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 fea-
tures and benefits of the process and the
specific features and benefits of the lens
product youre recommending. While
your explanation to the patient should besimple, it must be accurate. Your lab or
lens manufacturers representative can
help you with this information.
Will the patient appreciate the dis-
tinctions between these new lenses
and conventional ones?
In a word, yes. Well-designed, well-
measured, and well-fitted free-form lens-
es can provide enhanced results over
conventionally designed and producedprogressive lenses. Will the results be
dramatic for a -0.50 -0.75 x 180 wearer?
Perhaps not, but many eyecare profes-
sionals 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 progressiv
lens design to deliver crisper, sharper,
bolder vision. For wearers, this means
they receive advanced technology lense
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 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 patients prescription.
Some free-form lenses like the Carl
Zeiss Vision Gradal Individual,
Varilux Ipseo, and Seiko SucceedInternal Free-Form and Exceed
Internal Free-Form are customized fo
II. The Patient
Shamir Autograph
Part of the Shamir Freeform Family,
Shamir Autograph exhibits the future
of progressive lens design. Developed
with Shamirs proprietary Personalized
Freeform technology, Autograph
provides a tailor-made lens, exclusive
to the patients 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 Shamirs patented back-
surface design.
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No two fingerprints or snowflakes are ever
identical, and neither are your patients. Thats why
Zeiss developed breakthrough technology that
creates a premium progressive lens for each
individual patient. Gradal Individual allows you to
incorporate new measurements for trulyindividualized 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 Alike
Gradal Individual and Gradal Short
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PAGE 10
D
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. Ipseouses three fitting heights in 2mm incre-
ments14mm, 16mm, and 18mm.
Seikos 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 compen-
sates the corridor and the optics of the
lens simultaneously. Customizing the
corridor length gives the patient exactlywhat 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?
Yesfor 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 youll be able to
explain them to patients later. No onewill 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 youre 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 lens-
es. Use them as a demo as you explain
the advanced features of the lenses.
How can I justify the cost differen-
tial to the patient?
For most patients, cost is not the issue
when buying eyewear; the issue is receiv-
ing value for the money they spend. This
is especially true of lenses when patientsview 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 deliv
ers. The more value it delivers, the more
the patient will want to buy it. The key i
justifying the cost of free-form lenses is
to detail the features and benefits of theto 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 obviou
one is an oleophobic/hydrophobic anti-reflective treatment. In fact, some free-
form lenses like Varilux Physio
360, Signet Armorlites KODAK
Unique, and Seikos 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 lense
why would you want to have them
annoyed by distracting, troublesome andsight-reducing surface reflections? This
is especially true of free-form lenses
made with high-index lens materials.
Do I need to refract the patient
differently for free-form lenses?
No, there is no difference in the refracting
process for these lenses. Standard refract-
ing equipment and other ophthalmic
instrumentation should be used. Of
course, you will want to ask questions
about the patients lifestyle, viewing
needs and viewing distances, special con-
cerns like not wanting to drop their eyes
too far into the lens when doing near
work, and other questions you would nor-
mally 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 pro-
vide to the surfacing laboratory?
Some free-form lenses require no more
III. Prescribing and Dispensing
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P
than the usual measures you currently provide for traditional
progressive lensesthe patients 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 addi-tional measurements for more precise customization, including
vertex distance, pantoscopic tilt and face form (also known as
wrap these days) tilt. Varilux Ipseo and Indos
EyeMADE offer additional instrumentation to measure how
the patient uses his or her eyes. This information is then incor-
porated with the prescription into the design. Essilors DEFINI-
TY asks ECPs to pick one of eight standard frame shapes and
to include this information on the patients prescription.
While all surfacing laboratories will want to know the
frames A, B, ED and DBL measurements to determine if the
lens will cut out in the frame, some will use these data to cus-tomize 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 progres-
sive lens failures is inaccurate measurements, especially seg-
ment 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 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 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 measure-
ments. 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 thepatient 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 patients unique
head and eye movements. These data are used to personalize
the lens for the patients unique viewing habits during manufac-
a. I have dispensed free-form progressives and feel they are
superior to conventional PALs.
b. I have dispensed free-form
progressives and feel they are no
better than conventional PALs.
c. I have not dispensed
free-form progressives
but I plan to do so soon.d. I have not dispensed
free-form progressives
and do not plan to do so.
e. I do not prescribe or
dispense lenses.
A
32%
E
34%C
34%
Total respondents: 56
ECP Perceptions ofFree-Form Lenses
1. Which statement best describes you?
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 ordifficult prescriptions.
d. Dont know.
Total respondents: 53
A
87%
C 9%
D 4%
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.
Total respondents: 57
E68%
A
14%
B 9%C 9%
These results were generated via audience surveyduring the webinar presentation of Straight Talk
About Digital Lenses, 9/28/06.
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PAGE 12PAGE 12
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. Youmay also be asked for a face form tilt meas-
urement. 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 panto-
scopic 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 ZeissVisions 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 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. 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 all
patients?
Yes, free-form lenses are effective for
nearly every presbyopic patient, not just
because of their advanced free-form pro-cessing, but because, in most cases, man-
ufacturers are developing advanced
designs to use with free-form processing
techniques. This means that patients
receive the latest in lens design and tech-
nology 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 patients individual frame and Rx.
This kind of optics benefits just abouteveryone. It is especially suitable for
those with strong prescriptions, those
who have had poor results with prior pro-
gressive lens designs and those with high
cylinder in the prescription. Anyone who
wants the best optical performance avail-
able in todays progressive lenses is a
suitable candidate for customized free-
form lenses. Those who want the latest
advancements in lens technology are also
suitable candidates for free-form lenses.
Ive heard that free-form lenses may
be too complicated for staff to dis-
pense. Is this true?
Free-form lenses are no more difficult t
recommend, demonstrate, measure, and
order than any other progressive additio
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 o
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 membewho are not certified or licensed dispen
ing personnel will not have difficulty
working with these lenses once they hav
learned the fundamentals. This knowl-
edge and training can be obtained in
printed form from lens manufacturers,
professional journals, and continuing
education articles. Hands-on training ca
be provided by optical laboratories, lens
companies, and co-workers. In short,
free-form lenses are just as easy to workwith as traditional progressive lenses.
IV. Ordering, Fees, and Other Questions
DD
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
additional measurements over the stan-
dard 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 an
Varilux Physio are sold with Criza
Aliz with Clear Guard, Essilors top
of-the-line anti-reflective treatment
you cant 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 ZeissCarat Advantage AR coating. Be sure
to know your products availability
before you recommend it to a patient to
avoid disappointment and dissatisfac-
tion. A few quick mouse clicks on a
manufacturers or labs 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 youll 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 thosethat are available without it, your lab
will arrange to have that done for you.
Of course, some laboratories strictly pro-
duce uncut lenses for you to edge.
If youre comfortable edging and fin-
ishing 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 Free-Form 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 expen-
sive for many patients. In most cases,you will find that free-form lenses cost
modestly more than traditional progres-
sives, and considering the added features
and benefits, easily justify their addition-
al cost.
One way to position free-form lenses
to patients is to create a good-better-
best lens menu. In other words, create
tier system of lens prices for your pro-
gressives. The progressive that costs the
least is your good progressive. Think
of it as your basic value line progressivThis is probably an older progressive
design that still provides good results.
The better progressive is your middle
of-the-road priced progressive and has
additional features over the basic design
Your best progressive is your free-
form progressive lens. This one offers
the latest in technology and the most
features and benefits. Since patients bu
other 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 to
every patient. Let them decide if this is
what they want. If not, you still have
other choices that will meet their
needsbut not with all the features and
benefits of your best lens.
Can I verify free-form lenses with
my manual or automated focimeteThis is a common question and one wit
a simple answer: Sure you can. No spe-
cial 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 360Varilux 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.
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PAGE 14PAGE 14
some designs compensate the prescrip-
tion ordered for the patient due to the
individualized measurements provided
by the eyecare professional. Parameters
such as vertex distance, pantoscopic andface form tilt have an effect on the pre-
scription 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 eye-
care 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
Pentaxs Retina Forward Design (this
is the compensated Rx). These values
provide the best image quality at the
retina when the lenses are in the posi-tion of wear.
Which one do you verify? The com-
pensated oneit 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 free-form lenses to recommend for a
patient?
Choosing a free-form lens is no more
challenging than choosing any other pro-
gressive 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 havepatients 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 DEFINI-
TYprogressive because of its Ground
View Advantage.
Discuss the features, benefits, and
performance characteristics of various
lenses with lens manufacturers repre-
sentatives or representatives from labs
that supply these lenses. Next, read theprinted information provided. It usually
has good technical and clinical data,
wearer trail results, prescribing and dis-
pensing tips, and more.
Once you feel you understand all the
lenses, decide which one best matches
your patientsneeds. This may be the
easiest part of your analysis because
some of these lenses adjust their design
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 len
fits into your current selection of pro-
gressive lenses. In many cases, this will
become your best progressive lens
offering if you use the good-better-best system of lens choices for patient
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 1012 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 askin
them questions about their wearing
experiences. There is no better way to
determine if a lens has merit than weare
trial results. If it works, its a winner; if
doesnt, move on to something else.
Zeiss Gradal Individual
Carl Zeiss Visions 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 features
and benefits. Essilors DEFINITY design incorpo-rates Ground View Advantage, which improvesground level viewing for patients who need it,
such as golfers.
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