If, during an eye examination, your doctor has discovered a vision problem like nearsightedness, farsightedness or astigmatism, it’s likely that one of the next steps you’ll take will involve a phoropter. A phoropter is special instrument used to switch multiple lenses in front of your eyes to fine tune your vision.
Phoropters look imposing but are really just an ingenious way to quickly determine the exact vision correction needed by your individual eyes.
By having you look through the phoropter at the “Big E” chart (the Snellen chart), your eye doctor will help guide you toward lenses that correct your vision impairment by switching lenses within the instrument.
How does a phoropter work?
The process of switching lenses in front of your eyes is less involved than it may look. A phoropter is used to manually determine “refraction”—exactly how a lens must be shaped to correct your vision to a normal state, nothing more.
Phoropters are subjective however, based on your visual perception and responses to your eye doctor’s questions. Is your vision better, or worse? With this lens, or this lens? How about now?
There are other procedures and technologies available that automatically measure the refraction needed within your eye and produce a “prescription” measurement without your input. These are called autorefractors.
Special thanks to the EyeGlass Guide, for informational material that aided in the creation of this website. Visit the EyeGlass Guide today!