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As far as
improving vision, the lenses did quite well. The type of plastic
used was easy to mold, inexpensive, and polished to a smooth optical
surface. The lenses were sturdy, and could last for years with
proper care and use. They could even be tinted slightly so the
patient wouldn't lose them if dropped.
The very
first contact lenses were actually developed in Germany in 1927.
They were made entirely of glass and covered the eye completely.
By 1937, a new type of plastic was used instead of glass, but the
contacts still covered the entire eye. This was the case until
the 1950's when lenses were developed that only covered the cornea
itself.
Above: A contact lense from the 1930's.
Thankfully, these old types of hard lenses are essentially obsolete and are usually not recommended by eye doctors.
But there was a serious problem. These lenses, specifically the material they were made of (polymethylmethacrylate, or PMMA) could not properly transmit oxygen or carbon dioxide.
For the cornea to be operate effectively, it must be able to take in
oxygen and release carbon dioxide. Hence these lenses were
extremely uncomfortable for the user, and in addition required special
solutions to help water and tears to adhere to their surface.
The First Contact Lens
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