🎯 Target Refraction (Desired Correction)
⚠️ Actual Ablation Performed (Error)
Calculation Explanation
When an incorrect laser ablation is performed, the necessary correction is calculated as the vector difference between the target refraction and the actual ablation.
Mathematically: Correction = Target - Actual
This calculation is performed in dioptric power space (M, J0, J45) to accurately account for both the magnitude and orientation of astigmatism.
The spherical equivalent (M) is calculated as M = Sphere + (Cylinder/2).
The Jackson cross cylinders are calculated as:
J0 = (-Cylinder/2) × cos(2×Axis)
J45 = (-Cylinder/2) × sin(2×Axis)