Prescription Lenses — What to Know Before You Order
Written by MODI
When the ophthalmologist writes you a prescription, you're left holding a sheet of mysterious markings: SPH, CYL, AXIS, PD… In this article we'll explain in simple terms what each one means, how to choose the right lens type, and how the ordering process works.
What's written on your prescription
SPH (sphere) — the main number. A minus (−) means nearsightedness; a plus (+) means farsightedness.
CYL (cylinder) and AXIS — astigmatism correction. If these fields are filled in, the lens is made individually and a ready-made lens won't do.
PD (pupillary distance) — the distance between your pupils in millimeters. It's essential that the optical center of the lens sits exactly in front of the pupil — otherwise headaches and discomfort are likely. It can be measured on the spot in our stores.
Lens index — why one lens is thin and another thick
The higher the prescription power, the thicker a standard lens turns out. A high-index lens packs the same power into a thinner, lighter form:
| Index | Who it's for |
|---|---|
| 1.5 (standard) | Mild prescriptions (up to ±2.0) |
| 1.6 (thin) | Moderate prescriptions (±2.0 – ±4.0) |
| 1.67+ (ultra-thin) | Strong prescriptions (±4.0+) — also better aesthetically |
Coatings worth adding
Anti-reflective (AR) — reduces reflections on the lens surface. Especially noticeable when driving at night and in photos.
Blue-cut filter — blue light filtering for people who work at screens. It combines with a prescription lens — both functions in one pair.
UV protection and a hard coating — to guard against scratches.
And of course, the photochromic ("chameleon") option can be made to your prescription too.
How ordering works at MODI
The process is simple: come to a store with your prescription (or have your PD measured on the spot), choose a BARNER frame — any model can take prescription lenses — and a consultant will walk you through the lens options, timing, and price. We'll contact you and send a notification as soon as your glasses are ready.
Stores: Vake (Axis Towers) · East Point · Tbilisi Mall · Batumi Grand Mall. Fitting is free.
See the frames that take prescription lenses →
Read next: Lens Tinting — Which Color and What Percentage · Reading Glasses — The Complete Guide
Frequently asked questions
What do SPH, CYL and AXIS mean on my prescription?
SPH is the main power: a minus means nearsightedness, a plus means farsightedness. CYL and AXIS describe astigmatism, and if those fields are filled in the lens has to be made individually — a ready-made lens will not do.
Do I need to know my PD before ordering prescription lenses?
Yes. PD is the distance between your pupils in millimetres, and it is what places the optical centre of the lens directly in front of the pupil. If it is not written on your prescription, we measure it on the spot in store.
Which lens index should I pick?
1.5 suits mild prescriptions up to about 2.0, 1.6 suits moderate ones between 2.0 and 4.0, and 1.67 or higher is best from 4.0 upwards. The stronger the prescription, the more a thinner lens improves both comfort and looks.
Can a blue-light filter or a photochromic tint be added to prescription lenses?
Yes. A blue-cut filter combines with prescription correction in a single pair, and photochromic "chameleon" lenses are also made to prescription. At MODI blue-light lenses cost 105 GEL, photochromic 135 GEL and tinted 125 GEL.
Which frames can take prescription lenses at MODI?
Any BARNER frame. Bring your prescription to Vake (Axis Towers), East Point, Tbilisi Mall or Batumi Grand Mall and a consultant will confirm the lens options, timing and price on the spot. Fitting is free.
