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A Pho-what? What’s A Phoropter, And Why Do We Use It?

Developed in the early 1900s, the phoropter—that big black thing with all the lenses that keeps you and your optometrist from staring directly into one another’s eye during the entire exam—originally went by two different names depending which one you were using. The Ski-optometer was invented by Nathan Shigon, and the Phoro-optometer was developed by Henry DeZeng. His invention would later go on to become Bausch and Lomb’s Greens’ Refractor.

Each new model that was subsequently released become bigger and bigger, until the version we use today was developed in the 1960s.

The purpose of the device is to test individual lenses on each eye during an exam. Whether you’re nearsighted, farsighted or astigmatic, you’ll likely spend some time behind this machine. Using the phoropter, your optometrist can quickly switch multiple lenses in front of your eyes, trying to find the right combination for the best vision possible.

By switching varying strengths of lenses, your doctor can manually determine the refraction of your eyes, meaning he/she will know exactly how a glasses lens must be shaped or curved to correct your vision to a normal state. While autorefractors and aberrometers exist to automatically measure refraction, many optometrists, ours included, prefer to stay with the simple, manual method that has worked for so long.

Better one or two? A or B? How about now? And now?