It's perfectly normal for our eyesight to change over time. Having bifocal or varifocal lenses in your glasses or as contact lenses can help to correct these changes, while providing the convenience of a single pair of glasses or contact lenses

Why might I need bifocals or varifocals?

As we grow older, changes to the lens of the eye are quite normal – for example, you may start finding it harder to focus on nearby objects. This is called presbyopia. The lens changes shape as we focus on objects at different distances, but as time goes by, it becomes less flexible and our vision may start to deteriorate as a result.

Corrective lenses help to remedy this, but having to carry around separate pairs of glasses for distance and close-up vision can be inconvenient – and so can constantly swapping from one pair to the other. For convenience, many people opt for prescription bifocal or varifocal lenses, which are available in the form of both glasses and contact lenses.

What are bifocals?

A bifocal lens has two different areas of vision, divided by a horizontal line across the lens. The top portion helps with distance vision, while the bottom section handles close-up tasks such as reading. The sizes of the two sections may vary according to how much distance or close-up work your eyes typically do.

Advantages of bifocal lenses

• Help with both distance and close-up vision

• No need for two pairs of glasses

• Usually more cost-effective than varifocals

What are varifocals?

Varifocal lenses (also known as progressive lenses) don't have a separating line – instead, they gradually progress from top to bottom to optimise distance vision (top of the lens), intermediate vision (middle of the lens – for tasks such as computer work ), and close-up vision (bottom of the lens).

The main advantages of varifocals over bifocals

• They look just like ordinary lenses, with no distinct lines

• They provide an intermediate zone for middle distance vision

Your optician can advise on which type of lens might suit you best, based on your individual prescription and your lifestyle.

Are bifocals & varifocals easy to wear?

Getting the hang of looking through the various parts of the lens is the key to getting the most out of your bifocals or varifocals. You may experience a sense of 'distortion' at first – some people adjust to this immediately, whilst others find it takes a while. As with any new prescription lenses, opticians recommend allowing at least a month to get used to them.

Some opticians use a computerised camera to take images of your posture, head tilt and frame position, to provide fitting measurements and lens customisation. This can help to ensure your lenses fit and function just right.

Are they expensive?

Because bifocals and varifocals are more complex to create than standard lenses, they tend to be slightly more expensive, with varifocals tending to be costlier than bifocals. With glasses, choosing an inexpensive frame can help to keep the overall cost down.

Not sure what's best for you? 

Your optician can talk you through your options and help you make the best choice. Always visit your optician at regular intervals, not only to ensure you're wearing the right lenses for your prescription but also to maintain good general eye health.