AAOO Vertical Prism Simulator v1.3
Didactic model of vertical prism from line-of-sight position relative to the optical centre. ©AAOO 2026 Dr Grant Hannaford for University of Lancashire
Controls
Live calculation
Prentice’s rule
Δ = cF
c0.50 cm
F+4.00 D
Prism2.00Δ BD
Geometry
Additional ray offset+0.0 mm
Eye height+0.0 mm
Lens decentration+0.0 mm
Effective position+0.0 mm through OC
Viewing above the optical centre of a plus lens induces base down prism.
Object ray
Line of sight
Optical centre
Reference / image