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Crossbows Midi Progressive Moulds

Features of design

  • 16mm corridor length to full addition power
  • Minimum fitting height of 17mm
  • Low distortion soft, aspheric design
  • Individual designs for left and right eyes
  • Moulds in 1.498, 1.56, and 1.60 indices

This design manages to combine a soft design with wide distance, intermediate and reading areas. This means the Midi benefits from having low rates of change of mean power yet maintains good dynamic vision throughout.


Midi Design Dimensions

Short Corridor Design Base Curve and Addition Range for Ø81mm moulds:
Nom Base True Base n=1.530 Additions
1.00 1.25 1.50 1.75 2.00 2.25 2.50 2.75 3.00
1.50 1.40
3.50 3.40
5.75 5.70
7.75 7.75

Note:

  1. Ø81 mould is designed to produce Ø75/81mm Progressive lenses when used with gaskets.
  2. Other diameters and specific edge configurations are possible, subject to additional charges.
  3. Moulds with a centred design are also available for the manufacture of finished progressive lenses, subject to additional charges.