L&T: Lens Choices

Jun
2007

EYE-VOLUTION

HOW FRAMES INFLUENCE LENSES (AND LENSES INFLUENCE FRAMES)


By Vicki Masliah
Photograph by NED MATURA; Frame: DONNA KARAN DK1527, LUXOTTICA; Lens: COURTESY OF HOYA VISION CARE.

As much as eyecare practitioners know that the function of the lens is the most critical part of a pair of glasses, they know, just as well, that the patient is more likely concerned about how attractive the glasses are. For patient satisfaction, the finished product has to be a good marriage of frame and lens. As frame manufacturers have released new designs, lens manufacturers have created lenses that function well with the frames. Think about the progressive lenses whose corridors have gotten shorter and shorter, and the “B” measurements of frames have gotten shallower.

It can work in reverse as well. In the 1970s, lightweight plastic lenses began to allow comfortable wearing of larger (and larger) eye sizes. The frame manufacturers offered styles that brought a new terminology and pricing to the practitioner—oversize lenses. Larger frames became a major contributor to the lens/frame symbiotic relationship. The low index of refraction of standard plastic resulted in thicker edges in the large eye sizes. So lens makers started their R&D to develop higher indices to thin out the lenses and aspheric surfaces to make them look flatter. As the cosmetics demanded more thinness, frames started getting smaller again. Today the availability of thin, lightweight 1.67, 1.70 and 1.74 index lenses have opened the door to larger frames again, particularly in the sunglass market.

The desire for fashion-forward eyewear also affects the development of lens treatments. This is probably most obvious in the constant improvements being made in antireflective coatings. Now that more highindex products are being used, there are more reflections off the lens surface. AR coatings should be used on every high-index order, both for cosmetic and optical benefits. Fashion also feeds the tints and coating sales. Eyewear looks terrific when the lenses coordinate with the frame.

L&T spoke with a number of eyecare professionals and lab experts for their opinions on how lenses and frames influence each other at both the manufacturing and dispensing levels.

MARTY BREGMAN, OPTICIAN, MR. SPECS OPTICIANS, LYNN,MASS.
“In some cases frame designs have encouraged lens designs. This is most obvious with the large selection of short-corridor and very short corridor progressive lenses being offered. But probably, just as frequently, lens designs have encouraged lens designs. With each generation of progressive lens design, the induced cylinder is more controlled and visual clarity is improved, especially with the new digital surfacing. As base curves and adds influence the amount of induced cylinder in a progressive, we can choose lens designs that are most beneficial on a per Rx basis. Short-corridor progressives, with limited intermediate areas, created an opening for the near variable focus lenses and the opportunity for the patient to be offered a multiple pair choice.

“Frame selection absolutely influences the lens treatments that are paired with the lenses. When rimless and semi-rimless frames are used, an anti-reflective coating is a cosmetic must have. Of course, discussion of the optical benefits of AR is necessary with every fitting, but it is much easier to position with rimless jobs.”

KEN MITTEL, SENIOR VICE PRESIDENT, HIRSCH OPTICAL (INDEPENDENT WHOLESALE LAB), FARMINGDALE, N.Y.
“Fashion is cyclical and so is the frame and lens relationship. The fashion fluke of the enormous frames of the ’70s made the patients and practitioners look for thinner lenses. That started the seemingly endless development of higher and higher indices. Simultaneously, the frames got smaller and smaller. So, now we have very high-index lenses and very small frames. The index has allowed the frame sizes to become larger without compromising the thickness too much. We are definitely seeing larger sizes coming into the lab, but, on the whole, they’re not huge. It’s obvious, though, that the frame designers are not longer aiming for the smallest frame possible without looking ridiculous. On the other hand, I don’t expect they’ll get too large either. It’s a matter of patient comfort, foremost. Of course the larger sizes are beneficial in sunglasses for both eye and skin protection. Here we are again, where frames have driven lens design. When standard eightbase lenses are used in the wrap sunglass frames, there are absolute visual compromises. The compensated eight-base lenses were designed to provided improved vision in the wrap frames. This is why it is so important to communicate with your lab, to become aware of products like these. Even though so much of our work is sent to us by computer, we welcome ‘lens consult’ phone calls. We can help create an ideal pair of glasses.”

STEWART EISS, OPTICIAN, STEWART PAUL OPTICIANS, BROOKLYN, N.Y.

“There is no doubt the frame dictates the types of lenses we use in each order. The patient will choose the frame first, then we can streamline the ideal lenses for the frame. Larger frame sizes are returning, so it’s great that we no longer must fill them with the ‘Coke bottle’ lenses of old. The variety of high-index lenses offer a lot of choices, so we can increase the index as the Rx, frame size and decentration increase. Not just those factors determine the index we choose. The frame material also makes a difference. Plastic frames will tend to hide an edge thickness, whereas metal and rimless certainly won’t, so we adjust the indices accordingly. Of course the newest large sunglass lenses should be paired with lenses that control thickness and weight. The wrap frames also need ‘frame specific’ lenses. We find that, with the types of frames we offer, fashion happens automatically. If there is a lens treatment that enhances the look of the frame, the patient is anxious to incorporate it into the job. We just make sure the patient knows the choices they have available to them.”

ANDREW ISHAK, OD, ELKTON,MD.

“Frames equate with fashion and lenses equate with function. It’s always interesting to mix both. We certainly want the patient to look great in their eyewear, but in our practice, we always focus on function and the frames come second. We listen to the patient to determine their visual needs. Although the term ‘lifestyle dispensing’ has been around for quite some time, it is even more appropriate today because of the huge selection of lens choices. There is no end to the visual opportunities we can give the patient. So, most probably, it is patient need that really drives lens design. When patients understand how different lenses address different tasks, they are more likely to own multiple pairs of glasses. We tailor lens function to each patient and actually discourage frame choices that we feel will be detrimental to function and comfort. This is why we avoided the wrap frames for so long. We find the greatest patient satisfaction when we let the prescription and task specifics of the lens lead to the appropriate frame choice. Good lenses provide good vision. By customizing lenses to include to correct index, curves and treatments the improved cosmetic appearance just happens. We have been so successful with that approach and are grateful the lens designers continue to consider the patient.”

ROBERT MESSINGER,OD, HOBOKEN, N.J.
“Much as it might not be the ideal situation, frames definitely drive the patient’s choice in the glasses they wear, so it is logical that frames will also create the need for the appropriate lenses. It’s really all about cosmetics. A good looking frame is complemented by a good looking pair of lenses. At least we now have every opportunity to make every pair of glasses as attractive as possible. We have to strike a compromise between what the patient wants and what is most effective for them. Frame selection, of course, influences the progressive lens we use. And, as the frames have gotten shallower, the corridors have gotten shorter. So, I must warn patients that work at intermediate distances, the sacrifices they make when they lose intermediate power.

“Fortunately, thickness issues have already been addressed as the frame sizes start to get larger again, we already have a variety of options. Even so, we try to direct the patient to a reasonable sized frame.

“It’s all a balancing act. We want to keep the patients by keeping them happy and we also want what most answers their visual requirements. It’s apparent that the frame and lens manufacturers must look at each other to keep that balance.”

MARK MATTISON-SHUPNICK, CE DIRECTOR, JOBSON OPTICAL GROUP, NEW YORK, N.Y.
“There is no question that lens designs and frame designs feed each other. It is that relationship, fueled by advances in technology that have given us the great variety in frame and lens styles. The obvious example is the AO Compact that surprised the market with its short corridor. It opened the door for more manufacturers to create short corridor progressives. So much is fashion driven, yet the results are both fashionable and functional. The patients are interested in looking younger, so progressives in small frames are ideal. But, smaller frames also fit better, closer to the eye, and short corridors help the older patients reach the needed add power more quickly. The utility of the progressive is maximized.

“When frame companies compete to create unique designs, they force the lens manufacturers to find better ways to ‘fill the hole.’ We saw the great popularity of the threepiece mountings encourage better quality, drillable materials. To polycarbonate we added Trivex and MR10 1.67.

“The eight-base wrap frames resulted in the disappearance of quality optics, when practitioners had no choice but to put inappropriate Rxs on an eight base. Sophisticated lens technology has resulted in eight- base lenses made for these frames that eliminate the problem previously experienced.

“Every development in eyewear technology results in an effect between frames and lenses. Each effect aids in providing the profession with the ability to maximize eyewear function.

“As frame selections are made, the available lens choices can be compatible both cosmetically and optically. Fortunately, frame and lens companies as well as the labs that fabricate the glasses understand that and offer endless options.”


Vicki Masliah is director of professional education at Hirsch Optical, a Farmingdale, N.Y.- based wholesale laboratory.

 

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