Spectacle Frame Checks
Spectacle Lens Checks
BS Cyl Axis Tolerances
0.25DC > 16 degrees
0.50DC > 9 degrees
0.75DC > 6 degrees
1.50DC > 4 degrees
2.50DC > 3 degrees
Over 2.50DC > 2 degrees
BS Add Power Tolerances
Upto +4.00DS > ±0.12DS
Over +4.00DS > ±0.18DS
BS Multifocal Lens Positioning Tolerances
OCs > Less than 1mm
Heights > Less than 1mm
Pantascopic tilt - no more than 2 degrees
BS SVD BVP (and MF) Tolerances
Under 12.00DS > Less than 0.25DS
Over 12DS > 0.25DS (as for MF)
Cyl over 6.00DC > 0.25DC