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Rx Transposition Calculator

Convert between plus and minus cylinder notation — both eyes

Both forms are optically equivalent. New Sphere = Sph + Cyl  |  New Cyl = −Cyl  |  New Axis = Axis ± 90°

OD — Right Eye

Input
-2.00 / -1.00 × 180°

OS — Left Eye

Input
-1.50 / -0.75 × 90°

Transposed Results

OD — Transposed
Sphere
-3.00
Cylinder
+1.00
Axis
90°
Complete Notation
-3.00 / +1.00 × 90°
OS — Transposed
Sphere
-2.25
Cylinder
+0.75
Axis
180°
Complete Notation
-2.25 / +0.75 × 180°

Full Rx Summary

Original
OD: -2.00 / -1.00 × 180°
OS: -1.50 / -0.75 × 90°
Transposed
OD: -3.00 / +1.00 × 90°
OS: -2.25 / +0.75 × 180°

Clinical Applications

Transposition converts between plus and minus cylinder notation. Both forms describe the same optical correction and produce identical visual results.

Common uses: Converting prescriptions between lab notation standards, verifying prescriptions received from other providers, and reconciling differences between automated refraction and manifest refraction results.