. Why do some people require bifocals (

Bifocal lenses are used for people who are both nearsighted and farsighted. It is common for people who are over the age of 40 to begin to notice a change in their vision and require the need for bifocals. As we age, our eyes begin to have trouble focusing on objects at different distances away.

Explanation:

People have to wear bifocals most commonly because of a condition called presbyopia. This condition occurs naturally. It causes difficulties in the eye’s focusing abilities. Bifocals work to help the eyes focus more clearly, which is why people have to get them.

Explanation:

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