8. – 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.
9. • 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.
10. • 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.
11. • Sometimes the eye does not work properly,
due to a defect of view.
• These defects can occur to the people,
but also to animals
12.
13. MIOPIA
• 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.
14. HIPERMETROPIA
Hyperopia 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.
15. PREZBITISM
• Presbitism is the phenomenon of diminishing the
power of accommodation of the eye due to aging.
Presbyopia bad objects seen and
read about weight text too close to
the eye.
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).
16. 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).
17. 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.
18. 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.
19. Lenses can cause serious problems to the eye. For a simple
guideline to be followed avoid cleaning and wear them..
• What to do: • What not to do:
• -Wash your hands before • -Do not touch the lens
with your fingernails;
handling lenses;
• Do not dilute or re-
• -use solution for solution;
maintaining and • -Do not rinse lenses with
preserving fresh lens; tap water;
• -follow instructions from • -NOT borrow lenses from
an ophthalmologist. / to other people.
20. 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.
21. hout
an ge eye color wit
How you can ch econds
contact le nses in just 20 s
• 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.
