Enter a spectacle Rx once and get every derived form: vertexed Rx, transposition, spherical equivalent, near Rx, a trial contact lens suggestion, and an estimated uncorrected VA. Results update as you type.
| OD | OS | |
|---|---|---|
| Entered Rx | ||
| Transposed | ||
| Spherical equivalent | ||
| Vertexed Rx (@ 12 mm) | ||
| Vertexed spherical equivalent | ||
| Near Rx (add applied) | ||
| Trial soft CL suggestion | ||
| Est. uncorrected distance VA |
Cyl may be entered in plus or minus form. Vertexing applies F′ = F / (1 − dF) per principal meridian. Trial CL powers are rounded to 0.25 D steps (0.50 D beyond ±6.00) and common toric cyl offerings; verify against the fitting set you stock. Uncorrected VA is a population-average estimate from the spherical equivalent (Smith 1991; Raasch 1995) — real acuity varies with pupil size, accommodation, and chart conditions. Educational use only.