METHOD OF DETERMINING PROGRESSIVE OPHTHALMIC LENS Russian patent published in 2016 - IPC G02C7/06 

FIELD: optics.

SUBSTANCE: method includes selecting target optic function, determination of front and back surfaces of lens, which at each point have average value of sphere (SPH_mean), cylinder (CYL) and cylinder axis (γ_AX) and are non-rotationally symmetric aspherical surfaces, determination of first temporal part in temporal area and second nasal part in nasal area; determining first or second support axes for first temporal or second nasal parts. First and second bearing axis are set within [γ_T-20°, γ_T+20°] and [γ_N-20°, γ_N+20°], where γ_T and γ_N -central axis of astigmatism target optic function. Front surface is changed so that at first temporal part of value of sphere (SPH(G₁)) along first bearing axis exceeds value of sphere (SPH(⊥G₁)) along axis perpendicular to it, or on second nasal part of value of sphere (SPH(G₂)) along second bearing axis exceeds value of sphere (SPH(⊥G₂)) along axis perpendicular to it.

EFFECT: reduced image distortion while maintaining good definition.

21 cl, 108 dwg