Single Power lenses
As their name implies these are corrective spectacle lenses with the
same prescription over their whole surface and are available in an extensive range of materials and powers
They are used when you want to have the widest field of view for a specific focus – for example driving, intermediate or reading lenses, and are available in the widest possible range of materials and powers.
Bifocals
Bifocals are used when you need to be able to see 2 different distances in the same pair of lenses.
They are normally made with a distance correction in the top or main part of the lens and a close focus correction in the bottom or smaller area [segment] but they can sometimes be made with different combinations.
The reading segment is placed so that it doesn't interfere with your vision when you look in the distance portion of the lens but is easily accessible when you drop your gaze to look at something close to.
The segment can be made in various sizes and shapes depending on what you are going to be using your spectacles for.
The most common shape nowadays is a 'D' on its back so that the straight edge runs roughly along the same level as the top of your lower eyelid. The width of this segment can vary- generally from between 24mm and the whole width of the lens area [executive bifocals]
Bifocals are useful when you need to have easily defined areas, or if you need large or unusually placed areas for near vision.
Multifocals
Multifocals are lenses which have a gradual power change over their surface.
Generally the power alters from your full distance correction to your full near focus correction so that you don't have a noticeable dividing line on the lens surface, improving the cosmetic appearance of the lens.
This means that no matter how far away something is there is a place on the lens which will allow you to see it clearly.
There are lots of different designs of multifocal lenses available.
Each manufacturer makes at least a couple of variations to allow various options for your budget and optical requirements, as well as making them available in a range of materials and coatings.
The latest designs aim to give you the greatest ease of use with the least visual disturbance from distortion, especially around the peripheral areas.
Although these lenses can take a little while to settle down with completely, most people are able to wear them immediately without too much trouble.
Ipseo ™ Varifocal Lenses
As a Varilux Specialist Optician, Linklaters in Bexleyheath is now able to offer the
Ipseo ™ varifocal lens. Your head and eye movements are measured and combined with your spectacle prescription to provide a tailor made varifocal lens specifically designed to match your physiological needs, giving optimum varifocal performance and reducing adaptation time.
This lens is especially recommended for first time varifocal wearers and those who have previously had trouble adapting to other varifocal lenses. [more]
Both our practices are Varilux Specialist Opticianswww.varilux.co.uk and are fully up to date with the latest developments in Varilux lenses.
Occupational Lenses
There are times when 'standard' designs are not completely suitable.
For instance, Pilots, Electricians, Mechanics and Painters and Decorators need to be able to see a close object above their eye-line as well as having normally placed distance and reading vision. There are a range of occupational designs for use under these circumstances.
People who work on a VDU screen sometimes need a lens with a much wider intermediate area than normal, and specialist designs are available for this in both Bifocal and Multifocal forms.
It is also possible to get lenses specially centred [e.g. for archery/pool/billiards], or with a single bifocal set out towards the edge for golf.
