Spectacle magnification (OD/OS)
Computes spectacle magnification as Shape factor × Power factor, reported in the horizontal (180°) and vertical (90°) meridians.
Relative magnification is OD/OS per meridian.
Inputs
Thickness and distances in mm
Right eye (OD)
Left eye (OS)
Notes:
- Meridian powers are computed at 180° (horizontal) and 90° (vertical) from the spherocylinder and axis.
- Shape factor: SF = 1 / (1 − (t/n)·F1), with t in metres.
- Power factor per meridian: PF = 1 / (1 − h·Fv), with h in metres and Fv the back vertex power in that meridian.
- Spectacle magnification per meridian: SM = SF × PF. Relative magnification is OD/OS.
Outputs
Horizontal = 180°, Vertical = 90°. Values reported as ratio and percent.
Press Calculate.