Why so long to get glasses made?

Amazon Prime.  Drive Through pharmacy.  Pizza to go.  On demand movies.  Uber.  An app for just about anything (almost).

We are an “instant gratification, give it to me now and give it to me at the best price and highest quality with top customer service nation”.  Unfortunately, this is not a healthy way to approach life as the thrill of instant quickly fades. Worse yet, it breeds a level of expectation which feeds on itself and insures future experiences of satisfaction are slightly marginalized with each successive instance.

Enter the optical experience.  With more the rule than exception, it takes a minimum of one week in most instances and up to three weeks for a pair of prescription eyeglasses to be made.  Surely this is a result of laziness and a poorly designed system, right?  After all, I can order just about any item on Amazon and it will be at my front door in three days.  Why can’t eyeglasses be delivered to me faster?

It’s complicated.  Sometimes yes, often no.  There are many facets to the puzzle.  Let’s start with the actual selection of the eyeglass frame (into which your lenses are placed).

Most optical centers at doctor’s offices or stand-alone optical shops are not high turn-over inventory situations.  Just like an automotive dealership, the car on the lot is the one you drive away in.  The frame you pick is the one you will own (no hidden back room of large inventory – as frames are not cheap).  It is simply too expensive to have hidden inventory.  There are a few exceptions to this model such as cheap discount vision plans which have a small selection of frames on a rack which matches the inventory at their warehouse optical lab where the lenses are inserted to the frames to make eyeglasses.  Some discount retail shops have very limited frame choices, often less than 80 (most optical shops have 500-800 frame choices).  The retail shop will then electronically submit the order to their optical lab in China, also where their frames are made and fabricate the lenses.  It takes about two weeks for single vision lenses to be made and shipped from China to your U.S. home.  Quality is ho-hum and lens choices are about three or four options.

The vast majority of independent offices and even national chain opticals send the patient’s selected frame to their local or regional optical lab via courier or USPS/FEDex/UPS taking about one to three days.  Just like dental offices which utilize outside laboratories, the vast majority of eyecare centers with opticals utilize an outside laboratory especially for non-single vision prescriptions.  It is simply too expensive to stock lenses, own the equipment and pay for the space and employees in the lab unless it is very high volume.  Typically, the lens information is submitted electronically and received by the lab in advance of the eyeglass frames.  This allows the lab to begin the lens ordering and/or fabrication process.  Unlike most products people buy, when it comes to lens options there are thousands of combinations.  The first variable is the prescription.  The initial spec is the sphere (far-sighted or near-sighted).  Next is the cylinder or magnitude of a person’s astigmatism.  Then the location of the astigmatism on a 0 to 180 degree meridian (so 180 options just for this).  Then the add power for people who need extra help for reading.  The second variable is the lens material:  CR-39, Polycarbonate, TriVex/HiVex or several other ‘higher index’ materials for people who have more significant prescriptions.  Then the option of lenses that are called photochromatic or darken when exposed to UV rays.  A lens can also have a tint permanently applied such as for sunglasses.  The lens type, such as single vision, progressive, bifocal, trifocal etc. can also add more variables.  Next there are lens coatings such as scratch resistance, anti-reflective, hydrophobic…at least a dozen options here.  When all is said and done, there are literally thousands upon thousands of lens combinations in terms of lens options, treatments, purposes and shapes.  Stocking this multitude of options is simply impossible.

Many optical labs have the ability to “generate” lenses.  Essentially, a lens with little or no prescription is “surfaced” using various grades of polishing processes similar to the cutting, edging and polishing of a diamond or jewel mounted in a ring.  Progressive lenses are very complicated lenses requiring highly specialized, expensive and sophisticated equipment taking at a day.  Remember, this a custom-made product – not something pulled off the shelf and shipped to your home in three days.

Once the lens has been manufactured, lens coatings such as Anti-Reflective, scratch resistance and special UV blocking coatings are applied per the optician and patient’s choices.  It is worth mentioning that several days can be had just for proper application of the lens coatings to a person’s prescription lenses.  This often first involves placing the un-cut lens ‘blank’ which is typically a large 70mm round lens through a very specialized lens cleaning process then drying process in a vacuum chamber which is absolutely clean.  Any debris on the lens will negate a good coating process.  After hours of this, the lenses are then placed in special chambers for application of ionized vapors to apply the highly specialized coats of anti-reflective, anti-scratch, hydrophobic, oleophobic, uv blocking coatings – often a separate process for each one.  U.S. based optical labs invest millions in these state-of-the-art coating processes.

After these processes are completed the lens is ready for insertion into the eyeglass frame.  Only a portion of this process can be automated.  The patient’s frame is first placed into a tracing machine which makes a 3-Dimensional image of the lens perimeter needed to be machined from the finished lens blank.  The lens blank is placed into an edging or milling machine which applies this 3-D trace perfectly to edge down the lens to fit the frame.  It’s actually more complicated than this as the patient’s pupil centers must coincide with the optical center of the lens based on the frame dimensions.  The edged lens must then be hand-inserted into the frame.  Semi-rimless or full-rimless frames require extra steps, all by hand.  No robot has been made for these highly variable processes which require skill and balance between just enough force, very fine dexterity and sometimes the deft application of heat to the frame.   Because every lens will have a different prescription, material and therefore thickness not to mention different eyeglass frames for different lenses, assembly line automation is not an option.  Just properly inserting a lens is a delicate process which can result in damage to the frame or lens.  Then the entire lens fabrication process must be re-started and a new eyeglass frame ordered.

The finished eyeglasses now must get in line to be quality-control checked.  The lenses are optically measured to insure they meet the doctor’s prescription.  The lenses are checked to be free of defects.  Any defect will require re-fabrication.  Reputable optical laboratories do this.  Mail-order and Chinese fabricated eyeglasses rarely do this.  If all checks out, the eyeglasses are carefully packed and shipped to the optical/doctor’s office.  This shipping step may take one to three days, depending on the lab location, the vision plan, etc.  Many vision plans require the participating providers and/or optical shops to only use their lab, often only one or two in the entire country.

Once the finished eyeglasses arrive at the doctor’s office or optical shop, they are unpackaged, re-inspected, verified for patient name, model, prescription and often an initial ‘optical bench’ adjustment is made as the frame can lose its original alignment due to the lens insertion process, shipping, etc.  This step adds an hour to the process.  Last, the patient is notified their eyeglasses are ready so the patient can then have the eyeglasses finally fitted and adjusted.

Remember, this whole process assumes nothing goes wrong along the way.  Sometimes breakage occurs, lenses don’t get matched up to the proper frame right away and jobs can get backed-up during peak periods such as the end of the year when many people are using their vision plan benefits or health spending accounts.  Your eyes are highly specialized organs unique to you.  Perhaps you have a little more insight into what happens behind the scenes to make your eyeglasses to work best with just your eyes and appreciation for the time involved.

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