Contact Lens Specification

CONTACT LENS SPECIFICATION

Water Content 

  • What is meant by water content? 
    •  Low Water Content <50% High Water Content >50%

      Advantages

      Suitable for dry eyes

      Less susceptible to environmental changes

      Low dirt/dust deposition especially with PolyHema material (non-ionic)

      Advantages

      Higher oxygen permeability

      More comfortable during early hours

      Faster restoration of shape

      Disadvantages

      Low oxygen permeability

      Less flexible

         Disadvantages

        Not compatible with dry eyes

        Higher dirt/dust deposition especially with Hydrogel material (ionic)

     

    Diameter 

    • What’s the difference between diameter and graphic diameter? 
      • The diameter is the total length of a lens, including its transparent part 
      • The graphic diameter is only the patterned part of a lens, which excludes the transparent outer part. 
      • Bigger diameter would have a firmer fit
     

    Base Curve 

    • What is a Base Curve (BC)? 
      • This refers to the curvature behind your lens, which will sit on your eye. 
      • Bigger base curve would have a looser fit
     

    Expiration 

    • What does the expiration date on the bottle/vial mean? 
      • During the manufacturing of contact lenses, each lens gets sterilized and packed in an air-tight vial along with saline solution.
      • Beyond that date, the active ingredients within the saline solution can lose their form, becoming acidic or more alkaline and in turn, damaging the lens.
    • How long until you should dispose your lens? 
      • Each vial/botol will state the months disposable, usually it varies from 1-6 months.