Eye care professionals, including ophthalmologists and some experienced optometrists, often write astigmatism prescriptions using positive (+) cylinder values. This practice stems from decades ago when the equipment used to measure vision and manufacture lenses could only operate with positive measurements.
Our system automatically converts these prescriptions when you input a positive (+) cylinder format. However, if you’d prefer to manually convert your positive cylinder prescription yourself, you can use our Positive Cylinder Conversion tool to do so.
Enter your prescription
Your converted prescription
| Sphere | Cylinder | Axis | |
|---|---|---|---|
| Right Eye | - | - | - |
| Left Eye | - | - | - |