Saulo Garcia

I grew up inside an optical shop. My mother likes to tell how, as a kid, I would watch eyeglasses being assembled, play with the tools, and draw on the back of service order slips. The family business taught me early what a precise measurement and work done right are worth. I went on to spend more than twenty years as a software engineer, always keeping an eye on the optical world. Optogrid was born where the two meet: digital measurement technology (pupillary distance and fitting heights) built by someone who knows the dispensing counter from the inside.

Anti-Reflective Coating on Glasses: How It Works and Is It Worth It?

Anti-Reflective Coating on Glasses: How It Works and Is It Worth It?

June 18, 2026

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: What They Are, Causes, and When to See a Doctor

Eye Floaters: What They Are, Causes, and When to See a Doctor

June 18, 2026

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.

Double Vision (Diplopia): Causes, Types, and When It’s an Emergency

Double Vision (Diplopia): Causes, Types, and When It’s an Emergency

June 18, 2026

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.

How to Measure Your Pupillary Distance (PD): Ruler, Mirror, and App Methods

How to Measure Your Pupillary Distance (PD): Ruler, Mirror, and App Methods

June 16, 2026

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…

Vertex Distance Calculator: Compensate a High-Power Rx

Vertex Distance Calculator: Compensate a High-Power Rx

June 13, 2026

Compensate lens power for a change in vertex distance. Enter the refracted power, the refraction vertex and the as-worn vertex, and the calculator returns the power to order.

Eyeglass Frame Measurements: The Boxing System and What the Numbers on Your Glasses Mean

Eyeglass Frame Measurements: The Boxing System and What the Numbers on Your Glasses Mean

June 10, 2026

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.

How Accurate Does PD Need to Be? Eyeglass Prescription and Lens Tolerances Explained

How Accurate Does PD Need to Be? Eyeglass Prescription and Lens Tolerances Explained

June 10, 2026

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: How a PD or Centration Error Induces Prism

Prentice’s Rule: How a PD or Centration Error Induces Prism

June 10, 2026

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.

Glasses to Contact Lens Power Converter (Vertex)

Glasses to Contact Lens Power Converter (Vertex)

June 4, 2026

Convert a spectacle prescription to the equivalent contact lens power. The tool applies the vertex formula, which matters above about ±4.00 D, and returns the power to order.

Monocular vs Binocular PD: The Difference, When Each Is Used, and How to Convert

Monocular vs Binocular PD: The Difference, When Each Is Used, and How to Convert

June 1, 2026

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.