Spectacle Magnification Calculator

This tool is intended for educational and dispensing support use.

It calculates OD and OS spectacle magnification and the binocular difference at a chosen meridian.

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Common Parameters

OD

OS

Summary Output

Enter OD and OS spectacle parameters above, then submit the form.

How It Works

This version follows the old Java calculator pattern: it first calculates power at the selected meridian, then applies spectacle magnification using shape factor and power factor.

Shape factor depends on center thickness, base curve, and refractive index. Power factor depends on vertex distance and the power at the selected meridian.

It is useful when comparing OD and OS image-size effects and estimating binocular magnification differences.