Processing Kaenon's SR-91 Polarized Lenses - A Lab's Perspective

By Karen Stotz of Pech Optical
New technologies and exotic lens materials may present all sorts of logistical challenges for lab operations who choose to adopt them early, and ECP’s may hesitate before recommending exciting new lens technologies because they fear processing delays at the lab or the unknown results their patients may experience. However, early adoption of technological innovation is exactly what is required to provide your lab business a competitive advantage that can keep your business ahead of the competition. Ultimately, if integrated appropriately, a new lens technology offering can result in increased revenues and increased profits – something that any business is striving to achieve.

Kaenon Polarized introduced SR-91 lens material when the brand debuted in 2001. According to the company: “SR-91 is a proprietary lens technology that features the optical acuity of glass lenses along with the lightweight and impact-resistance of polycarbonate lenses. Plus the polarized SR-91 lenses – available in 4 different tints and a variety of Light Transmission Levels - are guaranteed not to delaminate, crack or split (ideal for drill-mounting applications).”

While these qualities may appear to be similar to the claims made about Trivex lenses or NXT lenses, it is important to note that neither Trivex nor NXT offer polarized lenses in both plano and semi-finish formats; therefore, evidencing that Kaenon’s SR-91 lens is truly differentiated from any other lens material on the market. As such, Kaenon Polarized markets the lens as the only “non-compromising” polarized lens solution that provides the wearer with unprecedented optical acuity, light weight, impact-resistance, and a guarantee against delamination, cracking or splitting – available in plano, semi-finish, and in the brand’s own Freestyle freeform progressive solution.

At Pech, we love to offer exciting new lens technologies like Kaenon’s SR-91 lens. Although new lenses can create new challenges, we have worked hard to distinguish Pech from our competition by offering unique products before our competitors do. We have worked extensively with Kaenon Polarized in an effort to optimize the surfacing, coating, and edging/mounting processing of the SR-91 lenses. We have learned that processing the SR-91 lenses are not significantly more difficult than polycarbonate or Trivex lenses. Nevertheless, we have learned that certain equipment – like MEI multi-axis edgers – has substantially contributed to improvements in the edging and mounting of these SR-91 polarized lenses into any type of frame mount.

Kaenon’s SR-91 lenses are catalogued in DVI. As a result, Pech receives all orders electronically via remote entry. Pech stocks a complete inventory of SR-91 semi-finish lenses in all base curves offered by Kaenon (1, 2, 4.25, 6.25, 8.25) and all 7 different lens tint / LTL combinations (Grey 12, Grey 28, Copper 12, Copper 28, Copper 50, Yellow 35, and Aqua 50). As soon as we receive the order via remote entry, our Special Customer Service Unit immediately pulls the lenses from inventory, trays the order, verifies the information, and matches the order with the Rx when the frame arrives.

By and large, surfacing techniques are not substantially different from surfacing polycarbonate or Trivex lenses. We surface to a center thickness of 1.6mm. Based on this center thickness, we find this mid-index semi-finish lens results in a relatively thin and very light lens as compared to other similar index products. We like the fact that Kaenon did not waste any time developing a freeform application for their SR-91 polarized lens. Based on a Shamir design for 6- and 8-base wrapped lenses, this special freeform progressive design is marketed as Kaenon’s Freestyle Progressive, currently with a minimum seg height of 19mm (ideal for larger sunglass frames – which is perfect for the current fashion trends).

For labs with equipment that can process Shamir freeform designs, the SR-91 semi-finish lens is a very good polarized lens to stock because you can limit your inventory carrying expense (because you don’t need to stock all base curves and tints in semi-finish PLUS all base curves and tints in traditional molded progressive lenses in each of the various add powers!). In today’s difficult economic times, stocking a semi-finish lens that can also be used in freeform progressives is extremely important for any lab business that is concerned with cash flow and inventory levels.

Finally, our experience has proven the SR-91 lens easily accepts the laser-etched progressive marks.

The SR-91 polarized lens is friendly to the AR and mirror coating process. In fact, Kaenon Polarized mandates back side AR and super-hydrophobic coatings on all SR-91 Rx lenses mounted in their own branded frames; and many of their Rx jobs include a front side flash mirror coating, too.

In addition to processing all of Kaenon’s branded Rx jobs, Pech also processes SR-91 semi-finish lenses (single vision and Freestyle freeform progressive) to be mounted in any other brand’s frame ranging from sport to fashion, full-rimmed metal or plastic to rimless drill-mounts, and a variety of notched semi-rimless mountings. In order to accomplish such a wide variety of edging and mounting applications, we rely on our MEI 5-axis edger. These edging machines make it possible for Pech to customize the bevel for any frame mounting. Customizing the bevel and edging with an MEI machine has greatly reduced the amount of unwanted compression that used to challenge our polarized lens mountings. Furthermore, this equipment also allows us to place a bevel on the same plane as the lens that is being edged. This achievement has substantially reduced the number of jobs that result in splayed temples. Reduction of waste at the edging/mounting phase translates to a better bottom line for the overall lab business. Finally, once a lens shape has been optimized and perfected to a particular frame, the lens shape can be saved into the MEI database in order to be replicated over and over again – to the same exact specifications.

Consider the competitive advantage to your lab business or optical practice if you could offer a “best in breed” product to your customers or patients … and if your competition could not! Particularly in today’s difficult economic conditions, it is more important than ever for labs and ECP’s to seek out and embrace innovative lens technologies in order to differentiate your product offerings from your competitors. At Pech, we concluded several years ago that revolutionary lens technologies like SR-91 lenses gave us just this type of competitive advantage.

Karen Stotz is the training manager at Pech Optical. Karen can be reached at [email protected]


Labtalk June 2020