A guide to the many parts of the human eye and how they function.

The ability to see is dependent on the actions of several structures in and around the eyeball. The graphic below lists many of the essential components of the eye's optical system.

When you look at an object, light rays are reflected from the object to the cornea, which is where the miracle begins. The light rays are bent, refracted and focused by the cornea, lens, and vitreous. The lens' job is to make sure the rays come to a sharp focus on the retina. The resulting image on the retina is upside-down. Here at the retina, the light rays are converted to electrical impulses which are then transmitted through the optic nerve, to the brain, where the image is translated and perceived in an upright position!

Think of the eye as a camera. A camera needs a lens and a film to produce an image. In the same way, the eyeball needs a lens (cornea, crystalline lens, vitreous) to refract, or focus the light and a film (retina) on which to focus the rays. If any one or more of these components is not functioning correctly, the result is a poor picture. The retina represents the film in our camera. It captures the image and sends it to the brain to be developed. The macula is the highly sensitive area of the retina. The macula is responsible for our critical focusing vision. It is the part of the retina most used. We use our macula to read or to stare intently at an object.

Myth: Safety goggles are more trouble than they are worth.
Fact: There are 500,000 eye injuries every year in the USA. 50% of these accidents occur at home. The leading cause of blindness in children is eye injury. 90% of injuries can be avoided by using proper eye protection.

Myth: There is no need to have your vision checked before you turn 40.
Fact: There are treatable eye diseases; glaucoma is one of them, which can show up before you turn 40.

Myth: Wearing poorly fit glasses damages your eyes.
Fact: The right eyeglass prescription is required for good vision. Poor fitting glasses do not damage your eyes.

Myth: Poorly fit contacts do not harm your eyes.
Fact: Poorly fit contact lenses can damage your cornea. If you use contact lenses, have them checked regularly.

Myth: Eating carrots will improve your vision.
Fact: Carrots are high in Vitamin A, which is important for a balanced diet. Eating carrots or other foods high in Vitamin A will not improve your vision. Taking large amounts of Vitamin A can be very harmful. People that do not eat a balanced diet can develop vision problems along with other problems as they age.

Myth: Sitting close to the television will harm your eyes.
Fact: There is no evidence that sitting close to the television will damage your eyes. If this were true, office workers that sit 8 hours a day 17 inches from their computer screens, would all be blind. Sit wherever you are most comfortable when watching TV.

Myth: Doctors can transplant eyes.
Fact: Doctors can transplant the cornea, but not the eye its self. The retina and optic nerve are part of the brain. When doctors figure out how to transplant the brain, they will be able to transplant the eye.

Myth: Scientists have created a Bionic Eye.
Fact: Scientists have been working on a microchip to replace damaged retina cells in a person's central vision. Other scientists have been trying to figure out a way to connect a camera directly to the brain. The eye and the brain do not work the same way a camera and computer do. Even after someone figures out how to make a bionic eye, they still have to figure out how to connect it to the neural circuitry of the brain. What they have created so far is a crude form of vision consisting of several dots of light.

Myth: Reading in dim light will damage your vision.
Fact: Reading in dim light can make your eyes feel tired. It is not harmful and cannot damage your vision.

Myth: Eye exercises will improve your vision.
Fact: Eye exercises will not improve your vision. This myth has made many people wealthy. Rolling your eyes around has no effect on your vision.

Myth: It is not harmful to look at the sun if you squint or use dark glasses.
Fact: The sun's ultra-violet light will still get to your eyes, damaging the cornea, lens and retina. Never look directly at a solar eclipse. The direct light from the sun can blind a person in less then a minute.

Myth: You can cure a black eye by putting a raw steak on it.
Fact: Putting a steak on your eye will do nothing except expose your eye to any organisms living on the raw meat. Get immediate medical attention, a black can be a sign of serious eye injury.

Myth: You can weir your eyes out by using them too much.
Fact: You cannot wear your eyes out by using them. Cutting down on reading or close work, will not help or harm your eyesight.

Myth: Doctors can only remove cataracts after they ripen.
Fact: Cataracts, unlike fruit, do not "ripen." It is up to you, and your doctor, to decide when to remove a cataract. Most people have them removed when the decrease in vision starts bothering them.

Myth: Too much sex, especially masturbation, can make you go blind.
Fact: Syphilis, a sexually transmitted disease, if left untreated can lead to blindness, dementia and death. This is where this myth came from.

Myth: Blind people have a sixth sense or extra ordinary talents.
Fact: Most People with (20/20) vision do not pay much attention to their other senses. Blind people have worked hard to develop their other senses to compensate for their vision loss. There is no sixth sense.

Myth: Blind people live in a world of total darkness.
Fact: Only a small percentage of Legally Blind people see nothing at all. Darkness is the eye telling you that there is no light on. People who are (totally blind) do not have the ability to see light, or darkness. They see nothing at all.

Myth: Strong enough glasses will help anyone who is visually impaired.
Fact: Refractive lenses (glasses) cannot correct all visual impairments. Glasses cannot fix eye conditions that involve the retina, optic nerve, or brain.

Myth: A dog-guide knows how to get its master where he wants to go.
Fact: The blind person knows where they are going, and how to get there, not the dog. The dog's trainer teaches it to respond to traffic, street travel, and the commands their master will give them. A blind person goes through a month long training program to learn how to use the dog.

Myth: All blind people read Braille.
Fact: Only 10% of Legally Blind people read Braille. Developing the sense of touch it takes to read Braille is difficult for older people who make up 66% of the blind population. Ninety percent of Legally Blind people have some usable vision and most of them can read print or magnified print.

Myth: You need to speak louder when talking to a blind person.
Fact: Blind people have poor eyes not ears. Talk to them as you would to anyone else. When in a room with several other people use their name so they know you are speaking to them and not someone else.

Myth: Blind people can always identify you by your voice.
Fact: When answering your phone, do you know everyone by voice? It is a good idea to identify your self when meeting a blind person.

Myth: In order to travel independently, a blind person needs a guide dog.
Fact: To travel independently most Legally Blind people do not even need to use a White Cane. Very few use dog guides. Approximately 1,300,000 Americans are (Legally Blind); 109,000 of them use white canes; 7,000 use dog guides.

Myth: All blind people are alike.
Fact: "The Blind" is a term used by groups with political and social agendas. People with poor or no vision come from all races and ethnic groups, rich and poor alike. Being Legally Blind is a bit more then a nuisance for the 76-year-old women loosing vision from Macular Degeneration. A college student, who has had 18 years of training in how to function without vision, and knows no other way, may think of it differently. A 45-year-old truck driver going blind from glaucoma may go back to school and get an office job, or he may retire early and collect disability. A 39-year-old lawyer loosing his vision will get training in Braille, find readers and learn to rely on public transit to do his job. The 52-year-old stock clerk, that rides a bike to work every day, has been legally blind all his life. Everyone finds there own answers in life its no different for people that have poor or no eye sight.

Myth: Blind people, to maintain secrecy and security, staff the snack bars at the CIA.
Fact: Under the Randolph-Sheppard Act, blind people are allowed to operate all food service and vending facilities in government buildings. This act was one the first government programs to help employ the blind. The program has nothing to do with secrecy or security in government buildings.

Myopia - (nearsightedness)
People with Myopic vision usually have eyeballs that are too large for their lens and cornea to focus light properly on their retina. Eyeglasses and contact lenses can usually correct this problem.

Hyperopia - (farsightedness)
Hyperopia vision is caused by the eyeball being too small for the lens and cornea to focus light properly on the retina. Eyeglasses and contact lenses can usually correct this problem.

Presbyopia - (aging eyes)
As people age, they often begin to have difficulty focusing their eyes for reading or close work. It is usually corrected with reading glasses. Some people may need bifocal of trifocal lenses.

Astigmatism - (distorted vision)
People with Astigmatism have irregularly shaped corneas. It is usually corrected with eyeglasses or contact lenses.

Cataracts
There are over 1 million Cataract operations performed annually in the USA. Cataract surgery is an outpatient procedure with a very high success rate. Due to the lack of modern medical technology in the developing world, it is also the world's leading cause of blindness. Over 16 million people are blind from cataracts.

Age-Related Macular Degeneration - (AMD)
This is a degenerative disease of the macula; the macula is the part of the retina responsible for central vision. There is no way yet of repairing the vision that has been lost, but if detected early laser surgery can help slow the progression of the disease. (AMD) is the leading cause of vision loss in people over age 65. Eight million people are legally blind from macular degeneration worldwide and as the population ages this number is expected to grow.

Glaucoma
This disease increases the fluid pressure inside the eye, leading to loss of side vision and eventually total blindness. The increased pressure destroys the optic nerve. With early detection, it can be kept under control with pressure reducing eye drops and surgery. Chances of developing it increase with age. There are over five million people blind from glaucoma worldwide.

Diabetic Retinopathy
This complication of diabetes is a leading cause of blindness among middle-aged Americans. The longer a person has had diabetes the more apt they are to develop diabetic retinopathy. Laser surgery can slow the progression of this disease along with management of blood glucose levels. There are 2.4 million people blind from retinopathy worldwide.

Retinitis Pigmentosa - (RP)
This rare inherited degenerative disease slowly destroys the retina. Signs of (RP) first show up in early childhood. The side vision is lost first. The Disease progresses over many years leaving the person with only a small portion of their central vision. There is on cure for (RP) yet. There are 1.6 million people blind from (RP) worldwide.

Eye Injuries
Over 1 million people are blind worldwide from eye injuries. 90% of injuries can be avoided by using proper eye protection. If you are reading this page now because you or a loved one has an eye injury, turn your computer off and get medical attention. Any eye injury is a medical emergency.

Optic Nerve Hypoplasia
With this birth defect the optic nerve that connects the eye to the brain has not developed properly, it is underdeveloped. This happens before birth leaving the child with mild to sever vision loss. In most cases, there is no known cause.

Retinopathy of Prematurity - (ROP)
This is an eye disease of premature babies. Soon after birth, abnormal blood vessels start to grow on the retina eventually destroying it. No one is quite sure what causes this disease, but premature birth and low birth weight are thought to be the main causes. With modern medical procedures, only 400 babies a year go blind from this condition. In the 1950's the number of babies blind from (ROP) reached epidemic proportions.

Neurological Visual Impairment (NVI)
Children with (NVI) have normal eyes, but a part of the brain responsible for seeing is damaged. It can be caused from a lack of oxygen before, during, and after birth. Diseases like meningitis or traumatic brain injury can also cause it. Many of the children with (NVI) are multihandicapped. Vision loss can be temporary or last a lifetime.

Ocular Albinism
With this inherited birth defect, people have no pigment or reduced pigment in their eyes, skin and hair. This pigment called melanin is needed for the full development of the retina. Children with this condition have mild to sever vision loss and are very light sensitive.

Coloboma
Coloboma is a Greek word, which means mutilation. People with Coloboma are missing a portion of the structure of the eye. The human eye develops between the fourth and fifteenth week of pregnancy. As the eye starts to develop, a gap opens on the underside of each eye bud. This gap provides a way for the developing eye to be nourished. This gap, called the optic fissure, has to close before the eye is fully developed. Coloboma is the incomplete closer of the optic fissure. Gaps can occur in the eyelid, iris, ciliary body, lens, retina, macula, choroid and optic disc. It can cause from mild to sever vision loss. Coloboma occurs in about 1 in 10,000 births.

Preventable Vision Loss
Over 90% of the world's blind people live in developing countries. Many diseases can be prevented with education in basic hygiene, proper nutrition and medical care. Conditions unheard of in the modern world like: Trachoma, Onchocerciasis (river blindness) and nutritional blindness (vitamin A deficiency), are the leading causes of vision loss in these countries.

• Reviewing vision problems, general health, current medications, working environment, hobbies, etc.
• Examining eyes for signs of possible disorders, including cataracts and retinal problems
• Evaluating current prescription
• Testing eyes' ability to see clearly at all distances
• Measuring the fluid pressure in the eye, which is an important test in detecting glaucoma
• Testing eye coordination and muscle control
• Measuring eyes' ability to change focus
• Reviewing vision problems, general health, current medications, working environment, hobbies, etc.
• Examining eyes for signs of possible disorders, including cataracts and retinal problems
• Evaluating current prescription
• Testing eyes' ability to see clearly at all distances
• Measuring the fluid pressure in the eye, which is an important test in detecting glaucoma

Ophthalmologists are medical doctors that specialize in eye care. They must complete four years of premedical school; plus four years of medical school; complete a one-year internship; and a three-year residency in ophthalmology. They detect and treat eye diseases, prescribe drugs and perform eye surgery. They also prescribe eyeglasses or contact lenses.

Optometrists must complete four years of undergraduate school, plus four years of graduate training in a school of optometry. They receive a doctorate of optometry. They can prescribe eyeglasses or contact lenses. They can detect diseases, but cannot practice medicine. They are not medical doctors. Some Optometrists have special training in fitting low-vision aids; they are called low-vision specialists.

Opticians have a two-year technical degree. They interpret prescriptions and fit eyeglasses. They can adjust repair and reproduce previously ordered contacts, eyeglasses and frames. They cannot examine or test your eyes.

There are so many beautiful eyeglasses to choose from, it can be easy to forget about the lenses. With a name like Elegant Eyes, you can trust us for the most advanced eyewear and lens technologies available. From resisting dirt to reducing glare, explore the state-of-art lens options available at Elegant Eyes.

If you suffer from allergies, your eyes may be bothered too. They may be red, itchy, and watery and your eyes and eyelids may even be inflamed. Having an exaggerated reaction to certain airborne substances.

What are the causes?
Susceptible individuals have an exaggerated reaction to certain airborne substances, such as pollen, ragweed, grass, mold, and animal hair. Whenever these people come in contact with allergens, their immune system reacts, and may cause red, itchy eyes.

How can it be treated?
Some people reduce exposure by staying indoors when pollen and mold counts are high; they also may invest in special air filters.

There are non-prescription eye drops that are specially designed to relieve ocular symptoms of allergies.

Who Invented

Louis Braille didn't invent Braille. As a boy he attended a school for the Blind in Paris, He learned how to read but not to write. Back then Blind People learned how to read raised letters with their fingertips. This form of writing was very difficult to read. In 1821 a soldier named Charles Barbier came to visit the school. He bought with him a system he had invented called 'night writing'. Barbier had designed it for Napoleon; who wanted a secret code that could be used at night. It proved to be too complex for soldiers to learn and was rejected by the army. Louis Braille realized how useful this system of raised dots could be for the Blind. He set to work simplifying it. His system used six dots instead of the 12 used in Barbier's code. Now Blind people could learn to read as well as write.

How Dose It Work

Perkins Brailler - slate & stylist - electronic Braille note taker

Before computer technology, the devices people used to produce Braille were as old as Braille its self. The Perkins Brailler works like an old fashion typewriter. Its six keys produce the six dots of the Braille cell. The slate is a simple device used to punch out the dots using a stylist. These devices are still in use today. Computer technology has begun to replace these devices with electronic Braille note takers, refreshable Braille displays and Braille embossers; but the old ways of producing Braille will still be around as long as sighted people keep using pens.

Braille Alphabet
(English Braille America Edition)

Punctuation Signs

The Braille cell consists of six dots, two wide and three high. The dots are numbered one through six: the letter (a) is known as (dot 1), (b) - (dot 1 2), (c) - (dot 1 4), etc. Grade One Braille, used in some children's books, uses just the alphabet and punctuation marks. Grade Two Braille, used for almost everything produced in Braille, is a form of shorthand. Grade Three Braille, used for talking notes, is super shorthand. There is also a code used for music and one for math and science.

• Keep all household chemicals, paints, pesticides, fertilizers tools, etc. locked up away from children.
• Almost anything that can splash into the eye can damage it. Wear protective eyewear when working with: detergents, cleaning solvents, etc. Never mix cleaning agents.
• Car batteries contain sulfuric acid and produce hydrogen gas while being charged. This is one of the gasses used to send rockets into space. Always wear protective eyewear when working with batteries. Know the proper procedures for handling batteries and jump-starting cars
• Never remove Safety guards from power equipment. Wear protective eyewear to protect against flying particles.
• Children and adults should use sports-specific eyewear to avoid sports related accidents.
• Consumer fireworks cause 2,000 eye injuries per year. The best protection is to leave fireworks to professionals.
• Ultraviolet and infrared light from the sun, welding arcs and tanning beds can damage your eyes; it may also contribute to age-related macular degeneration. Use proper eye protection and never look directly at a solar eclipse
• Never allow children to play with Laser pointers they are not toys. The light from a laser pointer aimed into the eye can be more damaging than staring directly into the sun.
• Keep older children's toys away from younger children. Do not let children of any age use flying toys and projectile-firing toys with out adult supervision. Three out of four of children's eye injuries happen when no adult is present.
• In the car, use infant and child safety seats, safety belts and shoulder harnesses. Keep children in the back seat away from air bags.
• To avoid eye infection do not share eye makeup or eye drops with anyone. Many bacteria, including the cold sore viruse (Herpes), can spread to your eyes and damage your vision.
• Do not let children play in areas where cats and dogs go to the bathroom. Roundworm (Toxocara) larvae in cat and dog droppings can cause blindness and other health problems. Wash your hands good after working in the yard, cleaning litter boxes, or handling animals. Have your pets dewormed.