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Bifocal contact lens simply means two
different focal points or two different optical powers. A bifocal
contact lens contains two different optical powers. Individuals with
vision disorder called presbyopia, use these type of focal lenses. They
are also used by people requiring a distance correction for myopia,
hyperopia, and/or astigmatism. Generally, when an individual views
something at close range, he usually looks down and when he views the
same thing from a distance, he looks up. James Franklin is the pioneer
in the field of bifocal contact lens.
The
earlier 'Franklin' bifocals were designed with the lenses for close
viewing in the lower half of the frame and the distance viewing lenses
on the upper frame. The lenses were simply cut in half and combined
together in the rim of the frame. Later bifocals were made by cementing
of a bifocal segment onto a larger lens. Recent trend of bifocals is to
mold a small reading segment into the lens. The latest craze is of
bifocal contact lenses.
You can chose from a variety of bifocal
lenses with reading segments which come in a variety of shapes and
widths. The current most popular is the flat-top or D-shaped segment
which is 28 mm wide. Bifocal lenses can be termed as the palceabo for
patients suffering from presbyopia. Presbyopia is a vision disorder in
which one loses the ability to read the print that is too close like a
book or a menu. People with this condition hold the reading materials at
arms length to focus on them. This condition usually occurs around the
age of 40. Presbyopia can be corrected by bifocal lens as it has two
powers in one lens.
Different
types of designs are used to create bifocal contact lenses. For example,
an aspheric design changes the power from the center to the edge of the
lens allowing intermediate distance correction. A translating design
includes near vision correction on the bottom and far vision correction
at the top. The bottom edge of these lens is flat to keep the lens from
rotating while blinking. Finally, a concentric design uses the center of
the lens for one power and the outside of the lens for the other.
Bifocal users however, are facing a new type of problem with the
advent of computers. Though all printed reading materials are easily
viewed with bifocals, computer monitors are generally placed directly in
front of users, but still close enough to require corrective lenses,
requiring bifocal wearers to tilt their heads up to view the screen. You
can purchase bifocal contact lenses with rebate when you buy discount
contact lenses online. You can chose from a variety of brands such as
Bausch & Lomb PureVision Multi focal, Acuvue Bifocal and Bausch & Lomb
SofLens Multi-Focal. You can also buy Focus Daily Progressives, Simulvue
38, Essentials Multi focal, Frequency 55 Multi focal and alike from a
reputed online retailer. You can also buy bifocal disposable contact
lens. All the contact lens come with contact lens case ad contact lens
cleaner to help you use and maintain your contacts.
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