Hard and Soft Contact lenses
What is the difference?
When considering contact lenses it is difficult to know where to start, and as technology is constantly advancing and adapting, many of us are unaware of all the options available. Your optician is the best person with whom to discuss and assess your options, but a little background information is always valuable, and enables you to consider your own specific needs and requirements and have a better understanding of what you are looking for.
Loosely speaking, contact lenses fall into two categories – hard and soft.
Hard contact lenses have existed for decades, gradually developing and improving in comfort and ease of use. The earliest experimental glass lenses were replaced slowly by plastic, and progressed to those now used known as Rigid Gas Permeable (RGP) lenses. Made from silicone polymers, they ensure the eye constant access to oxygen. Their rigidity makes them durable, resistant to deposit build-up, and since with correct care they are longer lasting than soft lenses, they provide better value for money.
Soft lenses come in many forms, most of which are to some extent ”disposable”, i.e. designed to be used on a schedule of frequent replacement. They are made of soft flexible plastics with an integral water content that ensures the surface of the eye a constant supply of oxygen. The most convenient variety, and a great option for first time lens users, is daily disposable lenses, which are simply worn for one day and discarded, without the need for cleaning or soaking2.
Extended wear lenses, a fairly recent development, may be worn continuously for up to thirty days before being discarded. The progression of technology has addressed concerns about infection from wearing lenses overnight, making them a viable and convenient option for those who dislike glasses and regularly lens cleaning. They are available in soft varieties and RGP forms.
Anything on this site is not intended in any way to be a replacement for, or as a substitute to, qualified advice you should always consult your doctor or other appropriately qualified person or service.
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