Patti S. is a member of the Ophthalmic Operations division at VSP.
The advent of the one-hour optical shops announced to the spectacle-buying world that a complete pair of eyeglasses can be churned out in an hour. Anyone visiting a mall or with access to advertising media will be able to attest to the fact that these purveyors exist and do make good on their promise most of the time. So why, you might ask, is it that you are asked to wait 7-10 business days for your order when visiting an independent eye doctor? A bigger “why” might be posed when something unforeseen happens and that 7-10 day estimate turns into an unfulfilled dream and you are left waiting even longer, lamenting your poor vision and cursing the beings responsible for the delay.
A pair of lenses can quite easily be cut to fit a frame and mounted within minutes if your prescription is simple and you order single vision lenses. The mechanics of this process are fairly straightforward, especially with newer, more technologically advanced equipment. This is not to suggest that skill isn’t necessary, just that newer equipment improves accuracy and speeds up the process. The majority of prescriptions, however, require that the power is ground into the lens through a step called “surfacing.” Surfacing doesn’t take very long either. Most independent doctors with onsite labs have the equipment to finish (cut and fit lenses to a frame) lenses but have to send orders to a wholesale lab when surfacing is required. One-hour optical retailers have surfacing equipment in-house, if they provide this service on all prescription types.
Manufacturers produce many types of “finished” single vision lenses in stripped down versions as well as those with premium options, such as anti-reflective coatings. A finished lens is one that is molded with all powers intact—not to be confused with the act of finishing, which cuts lenses to fit a frame. Doctors who finish lenses in their office will stock the single-vision products with which they are most confident and fit most frequently. They also maintain relationships with labs able to provide the full spectrum of lenses they favor. Lenses that require surfacing come in all materials, colors, and with virtually any treatment. Retailers specializing in expedited service keep an inventory of what they anticipate they will sell and have the ability to control what patients are offered because of their integrated model. They also know the frame models available through their dispensary, lending a degree of familiarity to their technicians, which contributes to the ability to offer such quick turn-around times.
Wholesale labs produce lenses for many customers and by necessity must be able to accommodate the varied product preferences and visual impairments of the doctors, opticians, and patients they serve. Consequently, they stock a broader range of lenses and accept almost any frame model. Although they can reasonably forecast what will be ordered, there are no guarantees. The benefit is that doctors and opticians can offer patients a full array of lens designs, materials, and treatments available, knowing that full-service wholesale labs will likely be able to fill their request. If the lens is not in stock, most can be ordered and received quickly, often the next day. These labs also have access to a network of sub-contract facilities able to produce specialty coatings and treatments.
The delivery estimates presented by independent practitioners differ from location to location, but it is fairly safe to say many still quote 7 to 10 business days. Most orders will be returned within this period, many sooner, and others later—sometimes much later. It is important to note that delayed orders are the exception. Wholesale labs wouldn’t stay in business very long if they couldn’t turn orders out, on average, within a few days. It is also worthwhile to understand that as technology advances, finer and more specialized products become available. Most often, this means slightly longer processing times, but it is well worth the wait. Still, the increase in turn-around time required for your highly personalized premium pair of lenses doesn’t always explain what sometimes appears to be an excessive delay, especially if you didn’t order something that necessitates subcontracting to a distant galaxy.
If lens surfacing and finishing processes are relatively simple and access to facilities able to apply treatments so convenient, why should there ever be any extended delays? There are a plethora of answers to that question. Nevertheless, a basic understanding of what typically goes wrong will address the most common issues and hopefully convey to you how unique your order is and why lens fabrication is an art in spite of the refined technology that enables precision surfacing and finishing.
Lens prescriptions have multiple components and typically can include one to many of the following elements: sphere, cylinder, axis, add, prism, and prism direction. The power of your prescription is measured in diopters, which occur in 1/8 diopter steps. There really is no limit to power, but most are less than +/-10.00, which is a pretty hefty correction but can go much higher. Sphere, cylinder, and add are measured this way (adds usually top out at about +4.00 and are only in plus powers). There are 180° of axis and prism (measured in prism diopters) is really not capped, but usually runs less than 4 or 5. Some conditions also affect factors like lens thickness, attachments, and whether lenses will be transparent or frosted, among other things. Then there are specific measurements, such as how far apart your pupils are and where in the frame an optical center or multi-focal height measurement will be located. A conservative idea as to the number of possibilities is 4.6 million, based only on what is really a limited assortment of prescription possibilities (no prism, add, or anything funky) and considering only one eye. Add prism power up to 5 diopters and 12 add powers and there are 612 million possibilities.
Your prescription and other measurements influence how your lenses will fit into a frame. One of the reasons delays occur is because the unique elements of your order, alone or in combination, affect how lenses work with a mounting. Not all frames are equal and certainly not all frames are suitable for all corrections. When a lab receives an order, they may be able to identify a problem job immediately and notify the doctor, who will in turn let you know that you should pick another frame. If this happens, you should do it, even if it’s the only chartreuse striped frame with an attached elephant nose in the western United States. Just do it and cry your bitter tears in silence.
Sometimes a lab will attempt the order and end up breaking the lenses or possibly the frame. In the latter situation, they have to reorder the frame and wait. If they break lenses that were ordered specifically for the job, they will need to reorder and wait, otherwise a new pair will be pulled from inventory. Depending on the lab and their relationship with the doctor, they may continue to try. If the frame is an unfamiliar model, there may be unforeseen pitfalls and you are the lucky trendsetter whose selection provides the education. Rest contentedly knowing that you helped the next patient selecting this frame get his or her spectacles back in a couple of days. Most unfortunate are the times, when after several attempts, it becomes apparent that either the frame is not suitable for ophthalmic use or that there is no acceptable way to mount your prescription in it.
There are any number of other causes for breakage, which will all add extra time to the delivery date. Higher-powered lenses are more prone to breakage. Equipment failures cause breakages and slippery coatings can allow lenses to slip during processing. A coating may not adhere correctly or in some other way your order fails quality control. The excuse nobody ever wants to hear is that someone made a MISTAKE! Yes, it happens to the best of us. Labs employ people and from time to time, they goof up. The most skilled technician will break lenses on occasion.
Frame and/or lens backorders are another factor contributing to longer waits. Labs have no control over this, but can and do offer alternatives. If your chartreuse striped frame with an attached elephant nose is on backorder, you might want to opt for the one with mouse-ears instead if you have an imminent job interview and want to look your best. If a lens is backordered, the lab will notify the doctor. Alternatives will be suggested, so if you’re not the sort of person who freaks out at the slightest change in lens design, you should consider going with the lab and doctor’s recommendation. If you are the super-sensitive type, remember that although designs do differ, many have similar characteristics and your doctor or optician can probably identify something comparable or the same design in another material.
The advantages of seeing a private practice doctor are many, among which is the golden opportunity to have access to the latest and greatest in coatings. Anti-reflection [AR] coatings are a must to those of us who make our living in this industry. Many of us actually turn away in embarrassment if caught in a pair of old beaters without AR. We also know that many of the premium coatings are more expensive, but well worth every penny and require 2 additional days to process—if the coating chamber is onsite. If not, add a day to get to the subcontract lab and one to return to the originating lab, thus bumping your wait time up 4 days. Other premium services and some unusual prescriptions require orders to be subcontracted. This is true regardless of whether you patronize a one-hour retail establishment or a private doctor.
The accuracy of the information about your spectacle lens order is imperative, so when there is any doubt about your measurements, prescription, materials ordered, or frame, the lab will call your doctor. If anything prevents contact with your doctor’s office, such as holidays, weekends, vacations, or simply an inability to connect, the job will be on hold until your information is confirmed. Again, we are dealing with the human element and wherever people and handwriting are at play, the need for confirmation is bound to arise from time to time.
Are these potential problems reason not to order glasses from a private practice doctor? No. All the potential delay-inducing circumstances that can frustrate you when your glasses don’t come in on time can happen at the one-hour place. The difference is that they usually promote the products carried onsite. If the materials for your order are not stocked in the store, your glasses won’t be on your face in 60 minutes. If any of the other problems mentioned above plague your spectacles, you probably won’t get them in that time either. Will they get most out on time? Yes. That is their business model and like the wholesale lab, they must perform according to the reasonable expectations their customers have.
Private practice doctors’ patients must have reasonable expectations as well. It’s a trade off much like buying ice-cream from a convenience store versus hitting the major supermarket. I can run into my local 7/11 and pick up a carton of chocolate, vanilla, or maybe choose from a few other flavors and be home in five minutes. I might have a limited selection and pay a little more, but in addition to ice-cream, I was shopping for instant gratification. On the other hand, I could go to the full-service grocery store and wander down the frozen confections aisle for hours locating the perfect combination of flavor, fat content, and price before heading home. It will take longer, but I will get what I want (even if I don’t know what it is when I embark upon this self-gratifying journey), and if lamb and banana is the hot new flavor, that will be my indulgence. I could run into lines or encounter other delays at either location, but my experience will usually be consistent with my expectations.
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It wasn’t too long ago that our choices in lenses were as narrow as “plastic or glass.” This was the predominant question posed to patients in the 1980s and even into the 90s, (even though relatively modern technological options were available at that time). During most of the 20th century, glass was the only material and the selection in lens designs presented to patients was usually limited to basic single vision, bifocal, and trifocal configurations.
