Transposition Calculator

This tool is intended for educational and dispensing support use.

It converts a spherocylindrical prescription from plus cylinder to minus cylinder, or from minus cylinder to plus cylinder.

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Prescription Input

Summary Output

Enter the prescription above, then submit the form.

How It Works

Transposition follows three steps:

  1. Add the sphere and cylinder to get the new sphere.
  2. Change the sign of the cylinder.
  3. Rotate the axis by 90 degrees.

This is useful for converting prescriptions between plus-cylinder and minus-cylinder notation.