for Your Dispensing Toolbox
By Gary Heiting, OD
Release Date: February, 2014
Expiration Date: March 1, 2015
Upon completion of this program, the participant should be able to:
- Learn how to choose the best suited progressive lens technology (conventional vs. digital), based on individual patient needs.
- Learn how modern conventional progressive lenses use advanced design technology to deliver some of the same benefits as digital progressives.
- Develop a simple strategy for selecting and fitting progressive lenses that provide the best combination of wearer satisfaction, value and profitability.
Gary Heiting, OD, is a licensed optometrist and is senior editor of allaboutvision.com. Dr. Heiting received his Doctor of Optometry (OD) degree from Southern California College of Optometry in 1984 and has held clinical positions at Ophthalmic Surgeons & Physicians, Ltd. (Tempe, Ariz.), Park Nicollet Medical Center (Minneapolis, Minn.) and Eau Claire LASIK (Eau Claire, Wis.). Dr. Heiting has also served as director of education and director of product development at Pentax Vision, Inc., a subsidiary of Pentax Corp. (Tokyo, Japan).
This course is supported by an educational grant from VISION-EASE LENS
This course is approved for one (1) hour of CE credit by the American Board of Opticianry (ABO). Course SJHI026
Generally speaking, having plenty of choices
is a good thing. But sometimes too many
options can lead to confusion, second-guessing and less than optimal solutions.
One could argue that a state of too many
options is what we find ourselves in these
days in eyecare when it comes to selecting
and recommending progressive lenses.
Progressives are available from many manufacturers in every lens material and treatment
imaginable, and the choice of progressive
lens designs has blossomed from a relatively
simple one—"soft" versus "hard" designs—to something far more complex.
In addition to multiple progressive corridor
lengths, we now have three broad categories
of lens designs to choose from: conventional
progressive designs, free-form (digital) progressive designs and personalized (individualized or customized) digital designs.
To ensure we're all on the same page, let's
review the definitions of these design types. Conventional progressive designs: In conventional progressive designs, the progressive
power of the lenses is molded onto the front
surface of a series of semi-finished lenses
(blanks), each with its own base curve for a
specific range of distance prescriptions.
To create the finished progressive lens,
the optical lab selects the appropriate semi-finished blank for the distance Rx and add
power, and the desired sphere and cylinder power are ground onto the back surface
of the lens.
One drawback of conventional designs (for
the optical lab at least) is the large number
of semi-finished blanks that are required to
service a full range of prescriptions. Also,
when conventional progressive lenses are cut
with conventional (non-digital) cutting tools,
finished prescriptions that are near the upper
and lower limit of the range for each base
curve have aberrations that can be noticeable
and bothersome for some wearers.
Free-form progressive designs: Free-form or
digital progressive lenses are made with a
computer-controlled, three-axis diamond
cutting device that can apply virtually any
curve to any point on the lens surface.
Free-form lens generators also are capable
of a much higher level of precision than
conventional generators: They can produce
curves on a lens surface in 0.01 D increments,
compared with 0.10 D steps produced by
Also, the creation of free-form progressives
eliminates polishing steps required when
conventional tools are used, which improves
the power accuracy and optical quality of
The primary advantage of digital progressives for wearers is that free-form manufacturing technology can produce lenses with
fewer peripheral aberrations than conventional progressive lenses made with conventional tools. The peripheral curves of free-form progressive lenses can also be adjusted
("optimized") to compensate for aberrations
caused by the average frame fit.
An advantage of digital progressive lenses
for optical labs is that a full range of prescriptions can be created with a much smaller
inventory of semi-finished blanks. Also with
free-form technology, the progressive power
of the lenses can either be molded onto the
front surface of a progressive semi-finished
blank (like conventional progressives) or it
can be cut onto the back surface of a single
vision semi-finished blank.
Despite these benefits of free-form progressive lenses, it's important to know that
digital progressives don't guarantee a greater
wearer experience—patient satisfaction
depends on the progressive design as well
as (and perhaps more than) the method of
Personalized digital progressive designs: Personalized digital lenses take the customization (or optimization) of free-form progressive lenses to another level. With these
lenses, in addition to the wearer's prescription and adjustments made for an average
frame fit, the power of personalized digital
progressive lenses is adjusted to take into
account the actual frame the patient selects
so it is tailored for the actual position of
wear of the lenses and the size and shape of
that particular frame.
Though personalized digital lenses feature
impressive design technology, they also are
the most expensive progressive lenses available, and they usually require specialized
dispensing equipment and skills to prescribe
and fit them.
And while some wearers will appreciate the
added degree of customization that go into
the fabrication and fitting of personalized
progressive lenses, it remains somewhat
unclear just how many presbyopes will find
these lenses provide enough added clarity and
comfort to make the extra cost of personalized digital lenses an unequivocal value.
So which type of progressive lenses are
Currently, less than 25 percent of progressive lenses sold in the U.S. are free-form
lenses (including both optimized and per-
sonalized digital progressives).
In a 2012 VisionWatch survey of eyecare
professionals, though 84 percent of respondents reported that they offer free-form
progressive lenses, more than three out of
four of their patients purchased conventional
The largest number of progressive lenses
sold—39 percent of the total—were classified
as premium conventional progressive designs;
24 percent were standard conventional
designs; 23 percent were free-form (digital)
designs; and 14 percent were value conventional designs.
Though the survey did not identify reasons
why free-form progressive lenses have not
supplanted lenses with conventional progressive designs, one possible reason is the high
degree of satisfaction that most presbyopes
experience with conventional progressive
lenses—especially those classified as premium
conventional progressives. Wearer trials of
the latest premium conventional progressive
lenses reveal overall satisfaction ratings that
exceed 90 percent.
And some premium conventional progressives such as Vision-Ease Lens' new Anthology
progressives featured in this product spotlight
are now incorporating elements of digital lens
manufacturing that are elevating the optical
performance of these lenses to levels comparable to free-form progressives... without the
premium costs associated with full digital
designs (especially when compared with the
cost of personalized free-form lenses).
CHOOSING THE BEST
GO-TO DESIGNS FOR YOUR
Given the advances in progressive lens tech-
nology and designs, the increased costs associated with free-form lenses and the current market statistics, which progressive lenses should
be the go-to lenses in your dispensing toolbox?
The key to progressive lens success in
today's marketplace is to develop a rational
and effective approach to presenting progressives lenses that: 1. Feature advanced, high-performance designs that you can recommend with confidence. 2. Are most likely to
delight your patients without breaking their
budget, and 3. Produce happy patients that
refer friends and family to your practice.
The new Anthology series of premium progressive lenses from Vision-Ease Lens were
designed with these important goals in mind.
GO-TO LENSES FOR TODAY'S
The Anthology series of premium progressive
lenses features three specific designs to satisfy
the unique needs of today's demanding pres-
Novel is a versatile, all-purpose progressive lens
with a soft, balanced front-surface progressive
design. Novel is designed for the broadest range
of wearers, prescriptions and frame styles; and
features a 13-mm progressive power corridor
length and 16.5-mm fitting height.
Novella is a short-corridor version of Novel
to accommodate smaller frames. With its
compact 11-mm progressive corridor length
and 14-mm fitting height, Novella affords
presbyopes a much greater selection of
smaller frame styles. And like Novel, Novella
features a soft, balanced design for easy
adaptation and wearer comfort.
Narrative is the most advanced Anthology
progressive and features a customized, digital
back-surface design for the most demanding
presbyopes. The free-form, backside progressive design of Narrative provides all the
benefits of Novel and Novella, and has even
wider optical zones for all viewing distances.
Narrative is available in both 13-mm and
11-mm progressive corridors for optimum performance in a wide range of frame sizes, and
can be further customized with position-of-wear measurements provided by the optician.
Anthology progressive lenses are available in a
variety of lens materials, including lightweight
and impact-resistant polycarbonate, plastic,
Trivex and super-thin 1.70 Thindex high-
For outdoor wear, Anthology progressives
also are available in Vision-Ease Lens' Coppertone and SunRx polarized sun tints, and with
photochromic treatments by Vision-Ease Lens
(LifeRx /Change Rx) and Transitions Optical.
(Availabilities vary depending on lens design.)
ADVANCED FEATURES OF
All progressive lenses in the Anthology
series—Novel, Novella and Narrative—share
common design and fabrication characteristics to optimize optical performance, comfort
and wearer satisfaction.
Large viewing zones, soft and smooth design: Progressive eyeglass lenses have been commercially available for more than 50 years,
and lens design expertise and technology
have continually improved since the first
progressive lenses were introduced in 1959.
Over the years, lens manufacturers have recognized three critical factors in producing
premium progressive lenses that offer presbyopes clear, comfortable, functional vision at
all distances: size of viewing zones, softness of
design and smoothness of power transitions.
Size of viewing zones: To determine the
required size of a comfortable distance
viewing zone in a progressive lens, one has to
consider the size of the fovea—the small
area within the central retina (macula) that
contains densely packed photoreceptors
responsible for high-resolution vision (cones).
The fovea has a visual angle of about 10
degrees. When looking straight ahead, this
translates to about a 7.5-mm zone on the lens.
But since the eye rotates from side to side, the
size of the clear zones in progressive lenses
for tasks such as reading, computer use and
driving must be made significantly larger.
If the maximum lateral eye movement is 15
degrees before a person turns their head
when viewing distant objects, the functional
viewing area of the distance zone of a progressive lens should be approximately 40
degrees—30 degrees plus 5 degrees to each
side of the center of the fovea (assumes a
13-mm vertex distance).
The Novel progressive features a distance
viewing zone with a functional design width
of 43 degrees, allowing ample room for comfortable distance vision. This is especially
important for nearsighted presbyopes who
tend to be keenly aware of any compromises
to their distance vision.
The intermediate and near zones of progressive lenses can be smaller and still provide
comfortable viewing, since eyeglass wearers
tend to rely more on head movements than
large, excursive eye movements to see clearly
when using a computer and reading, compared with viewing distant objects.
Novel provides a lateral intermediate viewing zone of 15 degrees and a near viewing
zone of 18 degrees, which have been proven
ample and comfortable by extensive wearer
trials (more on that later).
Novella features intermediate and near
viewing zones of 14 degrees and 20 degrees,
The intermediate and near viewing zones of
Narrative backside digital progressives can provide even greater width, depending on the
prescription and position of wear.
Softness of design: All progressive lenses
introduce some aberrations and unwanted
cylinder power lateral to the primary distance,
intermediate and near viewing zones of the
lenses. These aberrations are primary causes
of adaptation issues, such as an unwanted
feeling of movement (or "swim") in the wearer's peripheral vision.
Generally speaking, soft progressive lens
designs—those where these aberrations are less
pronounced and occur more gradually in the
lens periphery—are more comfortable and
easier to adapt to than "harder" designs where
aberrations occur more abruptly at the lateral
borders of the viewing zones. Also, vision tends
to be less blurred and distorted when looking
through the periphery of progressives with
soft designs versus those with hard designs.
Novel, Novella and Narrative all were
engineered to provide the softest progressive
design possible, while maintaining large,
distortion-free viewing zones for distance,
intermediate and near.
Smoothness: The smoothness of a progressive
design describes the rate of change of increasing add power from the top of the progressive
corridor to the center of the reading zone.
Shifting seamlessly from distance through mid-range to near requires a combination of smooth power changes and accurate placement of the entire progressive corridor (i.e.,
the degree of "inset" of the reading zone).
For the greatest comfort, clarity and binocularity, the wearer's eyes should remain well-centered within the progressive corridor when
looking through the lower half of the lenses,
and the design also should accommodate normal vertical head and eye movements wearers
make when working at a computer or reading.
For reading, a downward gaze of approximately 30 degrees is most comfortable for
most wearers. This translates to looking
through a point on a progressive lens that is
roughly 15 to 16 mm below fitting cross on
the lenses (assuming normal posture and an
average vertex distance and position of wear
for the lenses).
But many presbyopes begin to read higher
in the corridor, at a downward gaze of about
24 degrees (11 to 12 mm below the fitting
cross). This is especially true for many computer users who desire the "top of the page"
to be clearly visible.
Intermediate or mid-range viewing generally
occurs at a downward gaze of about 18 degrees
(8 to 9 mm below the fitting cross).
The designs of Novel, Novella and Narrative
progressives incorporate these general
guidelines for the smoothness of add power
progression, combined with extensive wearer
trials, to accomplish the goal of maximum
comfort and wearability.
Also, for comfortable computer vision and
reading, the intermediate and near viewing
zones of progressive lenses must be in the
right position for the eyes as they rotate down
and in. The design of Novel, Novella and
Narrative progressives includes a variable
inset design to ensure the location and path of
the progressive corridor is optimally aligned
for all wearers, regardless of the prismatic
effects of the distance prescription when the
eyes converge for reading.
In other words, the reading area for a high-
minus distance prescription has less inset than
a plano distance lens, which has less inset
than a plus distance power lens. This ensures
that the reading area is right where it is needed, given the different prismatic effects of
these lenses when the eyes are in a downward,
All this sounds great on paper, but how can
you be sure Novel, Novella and Narrative are
the type of go-to lenses that will fully satisfy
the needs and demands of your real-life
The affirmative answer to that question
(along with final optimization of the Novel,
Novella and Narrative designs) came about
by means of extensive wearer trials, according
to Vision-Ease Lens.
DESIGNED FOR WEARERS...
To finalize the progressive designs of the
Anthology series, designers conducted multiple field trials of Novel, Novella and Narrative lenses on large numbers of presbyopes
with a wide variety of visual needs.
The goal of these trials was to refine the
performance of each Anthology design and
maximize wearer satisfaction for a very broad
range of presbyopes with multiple and varied
The term Vision-Ease Lens uses to describe
this wearer "beta" testing and refinement of
Anthology progressives is "iterative design"
or "paper-people-paper." In other words, the
lens designers set out to create the most
comfortable, all-purpose progressive design
mathematically, then evaluated the performance of the lenses with real-life wearer trials,
then adjusted the design accordingly and
retested it in the field.
This process was repeated until the desired
outcome of an overall wearer satisfaction was
attained, according to Vision-Ease Lens.
When it comes to modern progressive lens
technology and fabrication, two statements are
- Advanced digital fabrication processes
cannot salvage a weak progressive design,
- A superior progressive design can be
undermined by poor fabrication processes.
For optimal performance and comfort, a
go-to progressive lens needs an excellent progressive design, but it also needs to be reliably
and accurately produced with state-of-the-art
tooling and fabrication processes.
To create the highest quality polycarbonate
semi-finished blanks for Novel and Novella
progressive lenses, Vision-Ease Lens uses
advanced, diamond-turned metal tooling.
Diamond-turned tooling is superior to other
methods of creating traditional front-surface
progressive lenses (e.g., stainless steel molds,
glass molds, ceramic molds) because it produces exceptionally smooth and precise surfaces that require virtually no polishing and
provide micron-level shape accuracy for
optimum optical performance.
Diamond turning directly transfers XYZ
data (mathematical points) into the mold, allowing for true progressive design replication accuracy.
Free-form 3D diamond tooling also is used
in the Vision-Ease lens fabrication facility to
accurately apply the distance prescription
on the back surface of Novel and Novella
progressives to a precision level of 0.01 D.
This advanced tooling also is used to apply
both the distance power and the free-form
progressive design on the back surface of
Narrative all-digital progressive lenses.
FITTING EASE AND ACCURACY
Finally, let's not forget the hands-on dispensing skills of the optician when it comes to the
performance of progressive lenses.
Even the best-designed, best-fabricated
progressive lenses can produce poor outcomes
if fitting measurements are inaccurate. An
advantage of Novel, Novella and Narrative
progressives is they don't require special fitting equipment or new, unfamiliar measurement techniques.
As with other conventional progressive
lenses, the only required measurements are:
prescription (including add power), monocular PDs and fitting height.
This is true even when fitting the all-digital
back-surface Narrative progressive, which is
already optimized for these average position-of-wear measurements: 13-mm vertex distance, 9 degrees pantoscopic tilt and 7
degrees face form angle.
However, if desired, Narrative lenses can
be customized with actual position of wear
measurements for vertex, tilt and wrap angle,
taken by you with the dispensing tools and
techniques of your choice.
The ease of fitting Anthology series of progressives is another advantage of making these lenses
the go-to progressives in your toolbox, especially
for offices with opticians who may not be skilled
at position of wear measurements.
Ease of fitting also enhances efficiency,
which can enable you to serve more customers
during busy days.
USING YOUR NEW TOOLBOX
After adding the Anthology series of premium
progressives to your dispensing toolbox, you're
ready for action. Here are a few tips to help
you use your new tools for greatest efficiency
and patient satisfaction:
- Start by describing the benefits of an all-purpose progressive design for your customer's
primary pair of glasses. Explain that while
progressive lenses cannot reverse presbyopia, a well-designed, all-purpose progressive lens can satisfy most visual needs most
of the time.
- Mention that two types of premium progressive lenses are available: conventional
designs (Novel, Novella) and fully digital
designs (Narrative). Describe how modern
conventional designs offer comparable
visual performance and comfort at a lower
price, creating room in a person's budget for
a second pair of glasses for specific needs
(prescription sunglasses, computer glasses,
sports glasses, etc.).
- Choose Novel or Novella lenses as the primary go-to lenses, unless the customer has
special needs. Examples of special needs
might include: A. A history of poor adaptation to multiple brands of premium conventional progressive lenses. B. A very strong
prescription (plus or minus) or high cylinder,
and C. A frame with unusual position-of-wear
measurements due to facial size or shape. Recommend customized Narrative lenses as
the primary go-to lenses in such cases.
- Offer the customer a satisfaction guarantee
with their new Novel or Novella lenses, and
tell them additional customization with
Narrative lenses is available (at an additional
cost) in the unlikely event they cannot adapt
to the premium traditional progressive lenses.
With so many options available in progressive
lenses these days, it's easy to become overloaded with information and confused about
the best go-to progressives.
To reduce the stress of too many choices,
consider cleaning out your dispensing tool-box and restocking it with a limited number
of premium progressive lenses to make the
lens selection process more enjoyable for
both you and your customers.
Choose progressives with a modern conventional design as your primary go-to progressive
lenses for at least 80 percent of presbyopes. For
the best value for your patients, choose lenses
with an all-purpose, wearer-tested design that
are fabricated with advanced tooling and processing techniques. Modern conventional
progressive lenses—such as Vision Ease Lens'
Novel and Novella progressives—provide
exceptional comfort and performance and can
be positioned at a more affordable price point
than fully digital designs.
Include at least one fully digital premium
progressive lens in your toolbox for patients
with special needs or who simply want the
most advanced technology available, whatever the cost. A fully digital design also can
be a good problem-solving option for
patients who have been dissatisfied with
more than one brand of premium conventional progressive lenses.
The new Anthology series of premium progressive lenses from Vision-Ease Lens that
includes both conventional designs (Novel,
Novella) and a customizable, fully digital
design (Narrative) seems to be a good fit for
the new go-to progressives in your dispensing