FAQs About Contact Lenses

Why aren't all soft lenses high water content?
There are several disadvantages to getting a soft lens to soak up more water. Firstly, because higher water content lenses contain less plastic they are more fragile. Firstly, this either means the lenses are easy to damage or that you have to make them thicker to compensate for the reduced robustness, reducing the effect of the higher water content - thick lenses transmit less Oxygen than thin ones. Secondly, higher water content lenses often tend to attract deposits more quickly making them harder to keep clean. Thirdly, the higher the water content, the easier it is for that water to be evaporated from the lens and cause the lens to become uncomfortable and less clear.

What are contact lenses?
What are "Hard" and "Soft" lenses?
Why does the cornea need Oxygen?
What are high water content lenses?
Why aren't all soft lenses high water content?
Do gas permeable contact lenses absorb water?
Which lenses are best?
What is astigmatism?
I have astigmatism - can I wear soft lenses?
What is presbyopia?
I have presbyopia - can I wear contact lenses?
What are disposable lenses?
Why are contact lens solutions needed?
Do I need to use protein-removing tablets?
Which solution is best for my lenses?
I've been told not to wear my lenses when in an aeroplane - why?
Can I swim in my contact lenses?
Do I still need spectacles if I wear contact lenses?
What is the difference between tinted and coloured lenses?

See also:
All About Contact Lenses
All About Vision
How to make a complaint