Presbyopia is caused by a natural age-related process that affects everyone from
the age of 45 on, regardless of whether or not they have always had normal vision
or have suffered from
Myopia,
hyperopia or
astigmatism.
Presbyopia is an increasingly inability to maintain near objects
in focus. People with presbyopia have to hold reading materials at arm's length
to be able to focus on the image.
DESCRIPTION
The crystalline lens loses its elasticity and doesn't change shape enough. Focusing
(accommodation) on near objects becomes more difficult.
SOLUTION
Presbyopia can be corrected using several different types of lens. Although all
lenses for presbyopia correct near vision, they have different characteristics.
Progressive lenses
Progressive lenses deliver clear vision at any distance thanks to a sophisticated
lens surface tailored to eye movements and correction requirements. Wearers make
a natural, seamless, strain-free transition from close to intermediate vision and
intermediate to distant vision.
Bifocal lenses
Bifocals deliver near and distant vision, but have a visible separation line that
is an obstacle for eyes, forcing them to make an abrupt transition. Bifocals are
increasingly rare.
Single-vision (unifocal) lenses
Reading or half-moon glasses can be used to perform near work such as reading, sewing
or writing. However, distant images are blurred, which means that wearers have to
take their glasses off and put them back on frequently or look over the top of the
lenses.
Mid-distance lenses
This type of reading lens gives wearers good vision at near and intermediate distances
of one to five