Blog | Optical Industry Insights, Guides & Tools for Opticians

Selling lenses online, you can already get pupillary distance from a photo, but segment height has needed the customer to be wearing the frame. We are building a way to measure fitting height, and the full dispensing set, from a single remote photo, no try-on required. Here is a first look.

Anti-reflective coating for glasses cancels lens reflections through thin-film interference, cutting night-driving glare and screen fatigue. How it works, who benefits, what it costs, and how to clean AR lenses.

Eye floaters are usually benign, but a sudden shower of new floaters or accompanying flashes of light can signal a retinal tear or detachment, a sight-threatening emergency that requires same-day evaluation by an ophthalmologist.

When a patient says ‘I’m seeing double,’ one question separates a correctable optical problem from a medical emergency. This guide shows optical staff how to triage diplopia and refer appropriately.

Pupillary distance (PD) is the measurement in millimeters between the centers of your two pupils. To measure it yourself, stand 18 inches from a bathroom…

The numbers stamped on a frame, such as 52□18-140, are the boxing system: eye size, bridge and temple length in millimeters. This guide decodes every frame measurement (A, B, DBL, ED), shows how they set frame PD and decentration, and how to tell whether a lens will physically fit.

There is a published answer to how accurate a PD, lens power and optical center have to be. ANSI Z80.1 and ISO 21987 set the tolerances a finished pair of glasses must meet. This guide gives the exact numbers and what they mean for measurement at the dispensing desk.

Prentice’s rule, prism equals decentration in centimeters times lens power, quantifies the unwanted prism created when the optical center is not in front of the pupil. This guide covers the formula, base direction, worked examples, and the vertical imbalance that anisometropia produces in down-gaze.

Monocular PD measures nose-bridge to each pupil individually; binocular PD is the total pupil-to-pupil distance. Near PD is smaller than distance PD due to convergence. This reference explains all four measurements, when each is required, and how conversion estimates work for dispensing.

Pupillary distance grows through childhood and stabilizes in adulthood. Learn when PD actually changes, why near PD differs from distance PD, and when re-measurement is worth doing.