Personal Sunglass Science, GOLF
Introducing the New Shamir Golf Progressive
By Barry E. Santini, ABOM, and Mark Mattison-Shupnick, ABOM
Release Date: August, 2012
Expiration Date: August 1, 2013
Upon completion of this course, the participant
should be able to:
- Understand the various environmental and visual challenges faced by golfers on the course.
- Learn how lens design and filtration can enhance vision performance for golfers.
- Clearly convey the one-type-fits-all approach to sunglass selection is outmoded and obsolete.
Barry Santini, A.A.S., ABOM, is a New York State licensed optician, is ABO certified and was awarded an ABO Master in 1994. He has been an owner of Long Island Opticians in Seaford, N.Y., from 1996 to present.
Mark Mattison- Shupnick, ABOM, is currently director of education for Jobson Medical Information LLC.
This course is approved for one (1) hour of CE credit by the American Board of Opticianry (ABO).
Course # STWJM513-1
This course his supported by an educational grant from SHAMIR
beyond the fundamentals
of general purpose lens
designs and gray lenses.
Today, delivering the right
eyewear to every patient
requires that your choices
be more advanced, activity-specific and age understanding when determining the lens design and
sun filtration that works
best. In this case, personalization is
key to one of the most important leisure
activities—golf. Introducing the Shamir
Golf progressive, a unique way to think
about the sport and the presbyope.
This goes well beyond our old, one-type-fits-all approach of tinting an old pair of
prescription lenses. The dawn of the Golf
Performance Sunglass has arrived, and
golfing numbers about 27 million people—nearly 10 percent of the domestic population. With a proven record to willingly
spend discretionary dollars in pursuit of just
a hint of improved performance, it's time
to take an in-depth examination of that
individual known as the American golfer.
THE GOLF OPPORTUNITY
A "core" golfer is defined as one who plays
an average of 37 full rounds a year and is
primarily male with a mean age of 40. That
says that a good majority is presbyopic.
Therefore, they are part of the Rx population that mostly owns only one pair of glasses, in this case, either a general purpose
progressive or a bifocal. For them, it's time
to consider a progressive designed especially
for the golfer.
Professionally educated with an average
income of $104,000, core golfers are
focused on any product that promises
improvement or enhancement of their
Core golfers are responsible for 87 percent of all rounds played and the same
amount in money spent on equipment.
With an average round lasting four hours,
core golfers can spend almost 150 hours
per year under the intense rays of the sun.
Addressing the negative effects this much
solar exposure can deliver has been the
primary reason eyecare professionals have
advised golfers to wear a proper sunglass.
But ensuring proper eye health alone is no
longer enough. First, there are significant numbers of golfing presbyopes, typically
struggling with their progressives or bifocals
resorting to single vision to get the blur out of
the putt. Single vision lenses can create discomfort and frustration when the right power
they're used to is not there. This gets worse as
add power increases. Next, the improper use
of sun tints, such as blue or very dark gray,
may actually impede their performance.
Research completed in 2008 by a major
athletic outfitter concluded that golf is the
most visually demanding of all sports. Common lens designs create problems; new
Shamir Golf meets the unique needs of the
golfer. Then, consider the visual, color metrics, glare and environmental challenges
faced by a golfer to best match filtration,
polarization and coatings.
AND LENS DEMANDS
Varying distances: The golfer's focus moves
from the ball to its destination; every stroke,
whether a drive or a putt, requires concentration. From teeing off on a 500-yard Par 5
hole, to the sinking of a 5-footer on the green,
very few sports require such critical visual
evaluations across distances that can vary by
a factor of up to 300 times. He or she calculates distances and terrain. The accuracy of
visual input is crucial to the hand-eye coordination needed for winning results.
Variable lighting conditions: As an outdoor
sports activity, the conditions that make up
the visual environment on the golf course
change constantly. During a four to five hour
round of golf, ambient lighting levels often
vary from bright and sunny to darkly overcast. Especially as low-level clouds move past
the bright sun, the golfer's eye has to contend
with a wide dynamic range of both illumination and shadow.
Varying backgrounds: The task of distinguishing and following a white 1.68-inch
ball against backgrounds that include light
sand, green grass, brown trees and overcast
to bright blue skies, poses challenges near the
limit of human visual sensitivity.
Varying ground contours and conditions: Local variations in the elevation, pitch, contour, grass height and wetness of the course
all must be properly factored and evaluated
to control the path of the ball.
Varying wind conditions: The amplitude and
direction of ambient wind influence all
aspects of ball control in a round of golf. It's
time for completely redesigned golf eyewear,
both in design and color.
There are six areas of concern and of prime
importance when prescribing and recommending the right golf lens. Three are visual;
the balance is environmental.
NEW GOLF PROGRESSIVE MEETS
THREE KEY VISION DEMANDS
The visual demands placed on a golfer dictate the importance of lenses that are as
absolutely free of any distortion or power
errors as possible. Particularly with wrap
sunwear, it is the responsibility of you—the
eyecare professional—to deliver the right
vision, in all the right places with the least
blur. That ensures that as little as possible
visually gets in the way of peak performance.
After studying the eye movements of golfers, Shamir's development team identified
three vital areas of focus for golf: far (viewing
the distant green), midrange (looking down
at the ball on the tee, fairway or green) and
close (filling in the score card). Distance, mid-range and near aren't any different from the
vision that any other progressive supplies but
it's the way Shamir Golf does it that counts.
In this new design, the size of the lens zones
and the resulting management of the periphery have changed. Overall, distance is wider,
with midrange redesigned to be longer with a
stable plateau of power and near smaller.
In an everyday, general use progressive,
distance vision and near are typically maximized. The large near facilitates excellent
reading in all instances; a clear, wide distance
ensures good driving and mobility. As a
result, the midrange is narrower, usable for
on demand arm's length vision but for special
tasks, it is often too narrow. As the add
power increases it gets narrower. In fact,
many higher add wearers (adds greater than 2.00) complain of the narrow intermediate at
the computer or when using a tablet. In that
lies the opportunity for this new progressive.
These higher add wearers are a large part of
the golf demographic. For them, it means
that conventional progressive lenses don't
deliver the optical power needed for focusing
on the ball where it's needed most. First,
presbyopic golfers require clear vision at the
tee and when putting. This requires a change
to the way the intermediate or corridor is
constructed. From a need point of view, the
add doesn't have to be as large since the
reading demand is for a scorecard and menu
rather than sustained reading. Therefore the
near size can be sacrificed. Secondly, golfers
make more than average use of their peripheral field of vision as they focus on the ball,
look out sideways to where they want the ball
to go and back down at the ball. Then when
swinging, this rapid motion requires overall
peripheral clarity to easily track the ball. As a
result, when balancing the design attributes
of a progressive, if additional clarity is
required for the periphery, the designer must
consider that when thinking of the final size
of the viewing zones required, especially the
near and corridor design.
Distance vision is critical to the golfer. General use progressives narrow the distance
field, especially as add power increases. It's a
method used by designers to improve overall
lens clarity by allowing a small amount of
peripheral blur above the 180. Haven't you
had patients complain about the peripheral
clarity of the distance when they look straight
ahead but turn their head? Our answer has
always been "point your nose." However,
narrowing any of the field of view can be
problematic since the game of golf involves so
many distances in specific postures. As a
result, having the distance be as wide as possible facilitates dynamic eye movement for the
golfer. The distance power of Shamir Golf has been optimized using free-form techniques and the "funnel" has been widened, i.e., peripheral blur is reduced in magnitude
while the location is pushed down. The result
is a wider, clearer distance. This is especially
true along the 180 where a golfer's sight crosses when viewing the flag and when following
the ball from the tee. The reduction in blur
perceived by the golfer is a result of slowing
the rate of change of unwanted astigmatism
and locating it farther down the lens. It
should be noted that this can't occur in isolation. Distance redesign must be accompanied
by a redesign of the intermediate and near.
CORRIDOR AND NEAR
Redesigning the corridor and near zone is the
key, then using the prescription, continue with
optimization of the near periphery. The pres-byopic golfer requires clear vision of the ball
at the tee and while putting. That's about 5
feet away, not the usual intermediate distance.
Only a small near is required for scorecard
visibility. Ordinary progressive lenses don't
provide golfers with the extra help needed for
the intermediate and peripheral viewing. The
too large near adds peripheral blur just when
focus and concentration are most important;
the lenses let the golfer down.
Shamir Golf has an intermediate with a slower rate of power change in the initial corridor,
the power held stable for a part of the corridor
ending in a small near. In this way, the rest of
the design can be balanced
to provide increased clarity
across the distance horizon
especially the periphery
along and just below the
180 line. In cross-section,
Fig. 1 shows how the
power is moderated to better suit the golfer's vision
demands. It's easy to see
how a regular progressive
quickly becomes unusable
for the golfer, delivering
too much midrange power
RX FOR THE GOLFER
At the same time, your lab creates the prescription centrally as a golf lens; the periphery is redesigned for the Rx and the frame
chosen using Shamir Prescriptor software.
By customizing the lens' power edge to edge,
using the actual vertex, tilt and wrap or optimizing it with the factory default values,
overall lens clarity is improved. Golf optimizes vision and provides a more comfortable golfing experience by ensuring sharp
viewing in all three critical focal areas—the
far distant green, the ball at the player's feet
and the scorecard, as well as enhanced
The compensated power for the prescription ordered is evidence that the lens has
been redesigned for the frame worn. In addition, the design of the lens periphery has also
been compensated to provide better vision,
reducing swim and blur. This can ensure a
golfer's eye maintains optimal depth perception and contrast sensitivity because even
minor prescription corrections can influence
whether a challenging hole ends up scored
with a birdie, par or bogey. Even when a
patient declares, "I see just fine without
glasses," an ECP should take the time to
demonstrate how minor prescriptions can
significantly improve their vision especially
while wearing sunglasses.
MEETING THE THREE KEY
Variable light levels, varying focal distances
requiring central peripheral clarity for instant
cues, contrast levels and topographical considerations dictate that maximizing depth
perception, enhancing contrast and reducing
haze are the remaining three visual challenges
in golf. They are:
Depth perception: To facilitate tracking a
golf ball against varying backgrounds and
ground contours, maintaining a good depth
of field is essential. Therefore dark lenses,
with low transmittance levels, are not conducive to maintaining good depth perception.
Most performance lenses designed for golf
feature transmittance levels approximately 15
percent to 20 percent greater than typical
general purpose sunglasses. Higher transmittance ensures a smaller pupil for increased
depth of field. See the recommended transmittance and colors in the online version of
Contrast enhancement: Improving the eye's
ability to see and track a golf ball against varying backgrounds and light levels requires
enhancing the edge of the ball. To help make
a golf ball more distinct and easier to follow,
changing the eye's habitual color response is necessary. In our vision, everything we see is
compared against our experience, i.e., what
we already know or are familiar with. The
color response changes are accomplished
through modification of the eye's tristimulus
curve, or firing profile of the conical color
receptors, is called chromatic contrast. The
altered tristimulus response curve improves
the eye's ability to distinguish and discriminate colors, as well as object edges, by alerting
our eye and vision that "something's been
changed." For the optician, it means using
some colors that are outside your comfort
level. It should come as no surprise then, to
discover that gray—the most recommended
general purpose sunglass color—is NOT
favored for golf, precisely because it is fundamentally a neutral filter, and therefore will not
affect a change in chromatic contrast. Where
increased visibility or edge enhancement of an
object is the goal, a changeup in chromatic
contrast helps follow the ball better, and is
described by sunglass engineers as "ball pop."
Blue light filtering: With the long expanses of
grass found on a typical course, overcoming
the haze created from evaporation requires
suppressing blue, the color most scattered by
the evaporating water vapor hanging in the
air. For this reason, a performance golf lens
will include colors such as amber, brown,
purple and green, to suppress the blue spectrum (Shamir Golf is available in brown and
green). Reducing blue light scatter is also
advantageous when tracking a ball against the
sky. In addition, the damage from the accu
mulation of high energy visible
(blue light) has been linked to
Polarized lenses? Visual evaluation of these factors is enhanced
through discrimination of the
difference in the amount of light
reflected by individual grass
blades. Therefore a substantial
reason why most performance
golf sunglasses don't feature
polarization is that these reflections from the blades are important in discerning the grain and contour of a
green. The golfer's eye may use both grass
blade reflection and deflection to assess
ground contour as well as wind direction.
The size, angle, wetness and sway of a blade
of grass are visually enhanced, by allowing
its full reflectivity. With polarized lenses so
well-accepted and proven superior for glare
reduction effectively sent to the bench in
competitive golf, how can we design a lens to
otherwise reduce glare and prevent eye
fatigue on the course?
COLOR, GLARE AND THE GOLFER'S EYE
Because most golf course real estate is grass, you might think that a sunglass that emphasizes green above all other colors should prove superior for golf. But shifting our tristimulus curve with too much green may actually impede discriminating ground contours.
Therefore golf specific tints are simultaneously designed to: As we said, shifting the tristimulus curve with too much green may actually impede discriminating ground contours. Therefore golf specific tints are simultaneously designed to: Filter short visible blue light, which reduces haze, allow some long-wavelength blue light, which improves ball color (blue white) visibility. They typically allow just enough green to enhance visibility of ground contours. Transmission curves can be seen to suppress peak yellow wavelengths to reduce dazzle the eye and contributes to eye fatigue. Lastly, these lenses allow more red wavelengths, which helps the eye to distinguish the tones of green and grassy contours.
Indeed, a lens featuring a very saturated green color might highlight grass as a whole, but the cues a golfer seeks are actually much more subtle. When a golfer "reads" a green, they're trying to subconsciously process all the factors that will combine to influence both ball speed and trajectory during a put: A green lens might highlight grass as a whole, but hide the cues a golfer seeks since they are actually much more subtle. When a golfer "reads" a green, they're trying to subconsciously process all the factors that will combine to influence both ball speed and trajectory during a put i.e., slope, grass length, moisture Level (in and on the grass), base (firmness of green), wind and grain, blades facing the same direction (Source: The PGA Professional).
Sunglass engineers can approach this through different strategies. Some try suppressing yellow, the color to which our eyes are most sensitive. Others favor blocking more of the blue wavelengths, which our eyes have the most trouble focusing. Each approach has its own merit. But even as one company's golf recipe will often yield a different color profile from their competitors, all types are designed to enhance the visual performance of the golfer.
Brown or deep rose (sunny days), orange/amber (low light) and purple/lavender in photochromics (handles the varying light intensity during 18 holes) are colors specially suited to golf. Review the transmission curves of the variety of lenses available. Golf's variable lighting conditions favor lenses, which employ the convenience of photochromic properties.
Frames featuring interchangeable lenses of varying densities may appeal or prove better suited to particular players. Another approach has been using a flip-up style sunglass. However, golf research has shown that the all-or-nothing nature of flip-up suns may actually compound visual fatigue.
Consistent with avoiding abrupt changes to the golfer's eye, gradient-density lenses have proven to be less desirable. A player's dynamic eye and head motions may interact with the lens's gradient density area, and can result in decreased performance on the course.
See Graph 2 as an example of a transmission curve and its color properties as a golf lens. Polarized Lenses? - Visual evaluation of these factors is enhanced through discrimination of the difference in the amount of light reflected by individual grass blades. So a substantial reason why most performance golf sunglasses don‘t feature polarization is that these reflections from the blades are important on discerning the grain and contour of a green. The golfer's eye may use both grass blade reflection and deflection to assess ground contour as well as wind direction. The size, angle, wetness and sway of a blade of grass are visually enhanced, by allowing its full reflectivity. With polarized lenses, so well accepted and proven superior for superior glare reduction effectively sent to the bench in competitive golf, how can we design a lens to otherwise reduce glare and prevent eye fatigue on the course?
YOUR LENS CADDY, THE FRAME
Golf performance also depends on the engineering of the frame. These characteristics
have been found to be essential in a frame
specifically designed for golf:
Lightweight: A core golfer spends an average
of four to five hours on the course during a
typical round; comfort is a major issue. Not
only should the frame be lightweight, it
should fit snugly, stay in place and resist
slippage, even in hot and humid weather.
The best models feature rubberized nose-pieces and temple grips. Stability is also
ultra-important, as players do not want their
eyewear to distract them from their game.
Choose heat resistant materials. Composite
plastics and titanium-nickel metals are
favored for their ability to retain their original
shape and to resist heat absorption.
Wraparound construction: Since golfing
depends so much on peripheral vision, non-distorting lenses that fully wrap around the
eyes are important to block glare and deliver
a wide, unobstructed field of view. Most
purpose-built golf frames feature 8 D to 9 D
base lenses in a semi-rimless construction.
When addressing the ball, the frame's rim
shouldn't distract a golfer's eye or influence
their head position. Ideally, frames should
also place the lenses close to the face—but
not too close—in order to facilitate air circulation and prevent the appearance of a
Deep lenses for looking down: When looking downward, nothing should distract or
require a golfer to modify or depart from
their favored head, neck and shoulder posture. Avoid any style with lower lens edges
that lay at or near the gaze angle. Advanced
golf styles can address this problem by
employing adjustable temples and bridges, to
help tailor fit an uneven head or optimize the
pantoscopic tilt of the lenses.
CHOOSE THE RIGHT EQUIPMENT
Consumer choice in sunglasses reveals a
picture often centered most on cost and style,
sometimes UV protection or "disposability"—in other words, every factor except
task-specific or high performance considerations. For the golfer, this is a mistake. They
spend significant time vetting both equipment and technique to extract every ounce
of advantage for their game. Help the presbyopic golfer choose sunglasses in the same
way that they select the best driver or iron.
Consider the right equipment for the job;
choose a separate pair specifically for golf—new and unique Shamir Golf progressive.