The following was written by Bill Evans and published in the Coolum and North Shore News, Ask the Professionals page on Friday, 25th November 2011.
Q: What are extended reading lenses?
A: Many people in their forties and fifties or older require reading glasses to counter the effect of presbyopia, which is a loss of flexibility of the lens inside of the eye. Depending on the person’s prescription, typical reading lenses may have only a limited range in which objects are clear, called a depth of focus. Some people may find their reading glasses are great for reading a book, but don’t have quite enough depth of focus to see documents further away on their desk, their computer screen, or for card games such as bridge. This is where an extended reading lens may help. Extended reading lenses have the full reading power down the bottom of the lens, then moving up the power gradually decreases so everything up to around 70 centimetres away is clear. If you wish to have a little more range in your reading glasses ask your optometrist if extended reading lenses would be beneficial for you.