Embed Size (px)
Citation preview
Prezentated by: Dogariu
Cerasela Manuela
Class: a IX-a E
Many times we wonder :
.
But first, let’s present the composition of the eye
– Light enters intothe eye through the cornea, passes through the transparent medium and reaches 3 on the retina, where it forms a small image, real and overturned the optic nerve from the retina into objects. The ramifications turn images into signals that go to create, he analyzes and creates a visual sensation.
• We see• objects• at• different • distances• from• eye• due to the ability of the crystalline lens to
accommodate. At normal eye the optimal distance vision is about 25 cm.
• People are able to focus both eyes on one object (they view stereoscopic).
• The principle consists in presenting an image from two different angles, then the eye gives these images into a single three-dimensional image.
• Sometimes the eye does not work properly, due to a defect of view.
• These defects can occur to the people,
but also to animals
MIOPIAMIOPIA
• Nearsighted eye sees distant objects clearly, the image points to "infinity" is formed in the retina, either because the eye is more elongated, either because residual swelling of the lens.
But well see distant objects than the eye. This inconvenience is corrected with diverging lenses (glasses or contact lenses) and by surgery.
HIPERMETROPIAHyperopia is a condition that is manifested by blurred vision. People who suffer from hyperopia see well at distance and seeing distant objects are closer than usual.
Glasses and contact lenses are the first therapeutic option (converging lens) and the second surgery.
PREZBITISM• Presbitism is the phenomenon of diminishing the
power of accommodation of the eye due to aging.
Presbitism can be treated, but the loss of focusing ability of the eyes can be corrected by using corrective lenses or glasses form or contact lenses (converging lens).
Presbyopia bad objects seen and read about weight text too close to the eye.
Astigmatism
• Astigmatism is an eye disease manifested by a distortion of the cornea. For people with astigmatism, all objects both close and distant, are deformed.
The image formed on the retina is blurred to the eye suffering from this condition (which may occur at birth).
Treatment of this condition includes both surgical methods, and external correction (by cylindrical glasses).
DALTONISM Is the inability to distinguish some colors from others (especially red to
green). It is a congenital disease caused by the failure of a portion of the retina or optic nerve.
A charge not figure written Daltons joined
Blindness can be corrected using a lens coated with specific spectrum of light to change as it passes.
Can be used at any age.Enjoy the freedom to do what you want.Do not restrict the visual field.Provides protection from television and computers.
• What to do:• -Wash your hands before
handling lenses;• -use solution for
maintaining and preserving fresh lens;
• -follow instructions from an ophthalmologist.
• What not to do:• -Do not touch the lens
with your fingernails;• Do not dilute or re-
solution;• -Do not rinse lenses with
tap water;• -NOT borrow lenses from
/ to other people.
Lenses can cause serious problems to the eye. For a simple guideline to be followed avoid cleaning and wear them..
Today increasingly more people use contact lenses to get rid of glasses (contact lenses with diopters ) or aesthetic reasons (colored).
Some contact lenses are unusual, even shocking.
How you can change eye color without
contact lenses in just 20 seconds
• Gregg Homer ophthalmologist at California Medical Stroma office technology discovered how people with brown eyes can change color forever.
•
• Lighteyes technology uses a laser set to a frequency that changes in blue-brown eyes. Laser energy removes the brown pigment, or melanin, in the first layer of the iris.
• The results of this procedure irreversible eye color change will occur after 2-3 weeks.
• This method has been tested on humans and could become a routine cosmetic surgery in the U.S. in the next 18 months. Citizens from others countries will enjoy the eye color change only after three years.
• The cost of such operations could reach 3,000 pounds, according to the doctor who invented it.
