Progressive power semi-finished spectacle lens blanks for astigmatic presbyopes

A method for producing a progressive power spectacle lens for an astigmatic presbyope, the method comprising:

• receiving a prescribed distance-vision optical power, a prescribed add power, a prescribed cylinder and a prescribed axis for the astigmatic presbyope;
• selecting a progressive power semi-finished spectacle lens blank having a progressive surface with the prescribed add power and with a base curve suitable for the prescribed distance-vision optical power, the progressive surface having been designed to optimize optical performance of a lens one surface of which is the progressive surface and another surface of which is a toric surface with a particular non-zero cylinder close to the prescribed cylinder and a particular axis close to the prescribed axis;
• and
• surfacing an unfinished surface of the selected semi-finished spectacle lens blank with a toric surface having the prescribed cylinder, the prescribed axis and a spherical curvature such that the progressive power spectacle lens produced from the selected semi-finished spectacle lens blank has the prescribed distance-vision optical power.

A method for producing a progressive power spectacle lens for an astigmatic presbyope, the method comprising:

• receiving a prescribed distance-vision optical power, a prescribed add power, a prescribed cylinder and a prescribed axis for the astigmatic presbyope;
• selecting, from a set of different progressive power semi-finished spectacle lens blanks for different combinations of base curve, add power, cylinder and axis, a selected semi-finished spectacle lens blank having a progressive surface with the prescribed add power and with a base curve suitable for the prescribed distance-vision optical power, the progressive surface having been designed to optimize optical performance of a lens one surface of which is the progressive surface and another surface of which is a toric surface with a particular non-zero cylinder and a particular axis closer to the prescribed cylinder and the prescribed axis than those for any other semi-finished spectacle lens blanks of the set having a progressive surface with the prescribed add power and with a base curve suitable for the prescribed distance-vision optical power;
• and
• surfacing an unfinished surface of the selected semi-finished spectacle lens blank with a toric surface having the prescribed cylinder, the prescribed axis and a spherical curvature such that the progressive power spectacle lens produced from the selected semi-finished spectacle lens blank has the prescribed distance-vision optical power.