An eye examination should leave you with a written prescription, a note of your pupillary distance if it was measured, and any observations the optometrist flagged about your eye health. It should not leave you trying to interpret what the numbers mean for frame choice — that conversation happens with the optician, not with a search engine.
What follows is about the paperwork, not the medicine. We are not qualified to tell you what your prescription means for your eyes, and this article will not try. It will explain what the terms on the page mean in plain language, and where each piece of information becomes useful once you start actually choosing glasses.
What exactly should you walk out with?
You should have a printed or digital prescription, dated, with the practitioner’s details on it. You are entitled to a copy — it belongs to you, not to the shop where the exam happened, and you can take it anywhere.
- The prescription itself, with sphere, cylinder and axis figures if you have astigmatism
- Your pupillary distance, if it was measured (not every practice records it automatically)
- Any notes on eye health — dryness, changes since the last exam, anything to monitor
- A recommendation on when to come back
If any of that is missing, ask for it before you leave. It is a normal request, not an awkward one.
What does the prescription actually tell you?
It tells you the correction your optometrist has determined for your eyes, expressed as numbers on a standard chart. What it does not tell you — and what we will not tell you either — is whether that correction is right for your lifestyle, how strong it should be, or how often you need retesting. That interpretation sits with the person who examined you.
What is genuinely useful to understand is the vocabulary. Terms like sphere, cylinder and axis describe the shape of the correction; base curve describes how the lens surface curves; pupillary distance describes the horizontal spacing used to centre the lenses in a frame. None of these numbers are yours to apply — that is what a dispensing optician does when the lenses are ordered — but recognising the words means the conversation moves faster and you are not guessing at what you are being asked to approve.
Why does pupillary distance matter once you start shopping?
Pupillary distance determines where the optical centre of each lens needs to sit relative to your eyes. Get it wrong and even a correctly ground lens can introduce distortion or eye strain, particularly at the edges of the frame.
This becomes relevant the moment you consider buying online rather than in person. Some retailers will ask for it directly; others infer it, which is a weaker approach. If you are weighing up an online purchase against an in-person one, it is worth reading what to check before buying glasses online and the real limits of buying glasses online before deciding which numbers you actually need in hand.
What should you flag before choosing a frame shape?
Anything your optometrist mentioned about your eye health, prescription strength, or the physical space available for lenses is worth remembering when you get to the frame stage — not because you need to solve it yourself, but because it changes what a dispensing optician will steer you towards.
Strong prescriptions, for instance, tend to sit better in smaller lens shapes with a narrower eye size, because there is less untouched glass at the edges to thin out or magnify. That is a fitting fact, not a medical one, and it is exactly the kind of thing worth discussing at the point of choosing a frame rather than after ordering one. The hub on choosing frames and sunglasses covers the proportions and comparisons that matter once you have your prescription in hand.
What lens options are worth asking about, and which are still unproven?
Coatings and lens materials are where the biggest practical decisions happen after an exam, and they are separate from the prescription itself. An anti-reflective coating, a scratch-resistant coating, a higher-index lens for a stronger prescription — these are choices you make with the dispensing side of the practice, informed by what the exam found.
Some marketing claims outrun the evidence. Blue-light filtering coatings for screen use are the clearest example: there is no strong consensus that they meaningfully protect eyes or improve comfort for most screen users, whatever the point-of-sale display suggests. It is fair to ask about it and fair to decline it. For a fuller picture of what is proven and what is still marketing, the lenses and coatings archive is a better starting point than a salesperson’s pitch.
What if the exam turns up something about sunglasses?
If your optometrist discusses light sensitivity or recommends tinted lenses, remember that the tint itself is cosmetic. Protection from ultraviolet light comes from a stated UV filter — look for UV400 or 100% UVA/UVB on the label — not from how dark the lens looks and not from what it cost.
A dark lens without a stated UV rating is worse than no sunglasses at all, because the darkness makes the pupil open wider while doing nothing to block UV, letting more of it reach the eye. This applies whether the frame is inexpensive or a well-known name. The sunglasses archive goes into how to check for genuine protection rather than assuming it from appearance.
What findings should never be treated as background noise?
Some things mentioned in an exam are not style considerations at all, and they should not be filed away for later. A sudden change in vision, eye pain, flashes of light, new floaters, halos around lights, or vision loss in one eye are same-day matters for a professional — not something to monitor, look up, or wait out. If any of this comes up during or after an exam, the appointment to book is with the practice, not a browser tab.
How does the prescription actually change frame shopping?
It changes what a dispensing optician will recommend for lens shape and thickness, but it should not dictate style on its own. Face proportion, colouring and how a frame sits on your particular nose and ears remain style decisions, and they are yours to make.
Where budget goes matters here too. A strong prescription might mean more of the spend is better placed in the lens than the frame — a genuinely useful trade-off to understand before you fall for a shape that will not suit the lenses it needs. Frame or lenses: where should your budget actually go? lays this out without pushing you towards a particular spend.
What should you do with the prescription once you have chosen a frame?
Bring both to the same conversation. A frame’s fit — how it sits on the bridge, how the temples sit behind the ears, how far forward the lens sits from the eye — interacts with the prescription in ways that are easy to miss if the two are treated separately.
This is also where routine maintenance starts. Frames shift slightly with wear, and a fit that was correct on day one can drift. Knowing how often glasses should be professionally adjusted is a fair question to raise at the same appointment where the lenses are fitted, rather than something to figure out months later.
What should you take away in one sentence?
A written prescription, your pupillary distance if measured, a plain-language grasp of what the terms mean, and a clear sense of anything flagged about your eye health — with any genuine warning sign treated as urgent, not filed for later reading.
Everything after that — shape, material, colour, coatings — is a styling and construction conversation, and the eyewear guide is built around exactly that half of the decision.
The Designer Glasses publishes general information and style opinion, not professional advice. We are writers and enthusiasts, not opticians, optometrists or dispensing opticians. Nothing here interprets a prescription, recommends a lens power, or tells you whether you need correction — only an eye examination can do that. If your vision changes suddenly, or you have eye pain, flashes, new floaters or halos around lights, treat it as urgent and contact an eye care professional the same day. Sunglasses should carry a stated UV rating: a dark lens without UV filtering is worse than none at all.