Physics of the human eye.
The human eye, what a complex but fascinating organ. It has the ability to see past the horizon and observe the different colors of a rainbow. The eye can be quicker then a race car but slow enough to witness a snail crawling across a beach. The eye can capture objects at various different angles, such as birds flying overhead or a person walking right beside you. Yes indeed, the eye is probably the greatest sense a person can have.
The eye is so vast and complex. To try and write everything about the eye would take a very long time. Compiling all the information and then putting it down on paper, a person could write another book. The eyeball it self weighs about 7gm., the volume 6.5cc., and its specific gravity 1.077. It measures 24.15mm. anteroposteriorly, 24.13mm, tranversely at 23.48mm, vertically in adult males and 0.5mm in each dimension in females. (3)
Because the eye is so complex, there are many questions that might come to mind when it concerns the break down or conditions that is brought upon the eye. 1st, What happens to the eye during the gradual age of time? 2nd, How do eye glasses or contact lenses influence the eye’s capability of seeing better? 3rd, In worse case circumstances, what occurs to the eye if there is trauma brought on like an accident that directly affects the way a person sees or if the eye is diagnosed with a disease that will eventually lead to blindness.
The best way to explain how the optical component of the eye works and fails is to compare a healthy normal eye to an abnormal eye. The eye, in general is sheltered by a protective covering known as the sclera which surrounds the eye except for in front where the cornea is located. The cornea
sits on top of the ...
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...r vision, should get an eye examination. Regular examinations are important, especially for older people and those at high risk groups.
End notes
1.“Websters New World Dictionary,” School and office ed. (New York; the world publishing co. 1971) 156, 322
2.“Idaho eye center”. Modern guides for eye care. ( Pocatello, Id.) 2002 3.Howard Bedrossian, M.D. “The Eye” A Clinical and Basic Science Book. (Blackwell scientific publications. LTD., Oxford, England.) 1958
4. Jonathan D. Trobe, M.D. “The Neurology of Vision” Contemporary
Neurology series. (University of Michigan Medical Center. Ann Arbor, Michigan.) 2001
5. “Internet” (April 2003) Google: http://www.allaboutvision.com/conditions/
6. http://members.aol.com/ScienzFair/eyecam.htm 2003
7. http://www.callpe.com/support/spectral.html 2003
8. http://district125.k12.il.us/faculty/smcgrath/eye/eyechart.htm 2003
Simpson, J. A., and E. S. C. Weiner. The Oxford English dictionary. 2nd ed. Oxford: Clarendon Press; 1989.Print.
Optometrists have accepted vision therapy, which is a medical treatment for optical muscle disabilities, as a feasible treatment used for eye related problems; claiming the treatment can strengthen vision and give the patient the opportunity to understand visuals quicker and clearer (Press). Vision therapy originated in the 1950s and over the past 25 years, has gained popularity, mainly because of new technological innovations in the field of treatment. Generally, vision therapy is prescribed as a measure mainly for people between the ages of 3 and 18. With the results from a comprehensive series of eye tests, the optometrist can work with the patient using special instruments—prisms, filters, occluders, and eye lenses—and strengthen the eye muscles, thus improving sight. According to optometrists in favor of vision therapy, these methods of treatment using these instruments function as safer routes to repair eye disabilities. Although vision therapy can yield favorable results, the practice as a treatment for innate eye disabilities has been in hot debate lately; as it can exceed $8000 and insurance companies do not cover the treatment. For decades, insurance companies have refused to accept vision therapy as a legitimate method for repairing eyesight (Boink). Concomitant with lack of insurance, the cost for a full treatment can exceed $8000, and doctors cannot guarantee a successful outcome. Recently, parents of children with eye related disabilities, such as amblyopia (lazy eye) and strabismus (cross-eye), and doctors have attempted to cooperate with public schools to allow families access to school-funded doctors to practice vision therapy. With a tight budget, most schools cannot afford to supply vision therapy, and a...
Blindsight is often understood as supporting certain claims concerning the function and the status of the phenomenal qualities of visual perceptions. In this talk I am going to present a short argument to show that blindsight could not be understood as evidence for these claims. The reason is that blindsight cannot be adequately described as a special case of seeing. Consequently, it is not possible to draw inferences from it concerning the role of the phenomenal qualities for seeing.
The Circulatory System is a transportation and cooling system for the body. The Red Blood Cells act like billions of little mail men carrying all kinds of things that are needed by the cells, also RBC's carry oxygen and nutrients to the cells. All cells in the body require oxygen to remain alive. Also there is another kind of cells called white blood cells moving in the system. Why blood cells protect from bacteria and other things that are harmful. The Circulatory system contains vein arteries, veins are used to carry blood to the heart and arteries to carry the blood away. The blood inside veins is where most of the oxygen and nutrients are and is called deoxygenated and the color of the blood is dark red. However, blood in the arteries are also full of oxygen but is a bright red. The main components of the circulatory system are the heart, blood, and blood vessels.
An inspection of the modern animal phyla will reveal that eyes are just as diverse as they are complex. Some organisms like the rag worm have pigmented cup eyes while other like he box jellyfish have two lens eyes and two pairs of pigment pit eyes. To account for the diversity in eye structure, we must first examine the eye ‘prototype’, the original structure that was acted upon by evolution. The simplest organ that can be considered an eye is composed of a single photoreceptor cell and a single pigment cell, without any lens or other refractive body (Arendt, 2003). Such organs are know as eyespots, and...
Eyes are the ‘organ of sight or vision; the visual sense; the sense of seeing’ (Biology-Online). The eye is an organ that detects light and sends signals along the optic nerve to the brain. The eye allows for light recognition and the ability to differentiate between colors, and light and dark. The eye is approximately 2.54 cm wide, 2.54 cm deep and 2.2 cm tall. The human eye has around 200-degree viewing angle and can see and detect more than 10 million colors and shades. This essay is going to look at ways of seeing. The possible problems with eyesight, and eyes of various kinds. It is one of the most rare problems today that is affecting people, all over the world. Around the world an estimate of 4 in 10 people have perfect vision/sight (BBC). The population of the world right now
Pearsall, J. (ed) 1999, The Concise Oxford Dictionary, Oxford University Press, New York, p. 1209.
The four main components of the eye that are responsible for producing an image are the cornea, lens, ciliary muscles and retina. Incoming light rays first encounter the cornea. The bulging shape of the cornea causes it to refract light similar to a convex lens. Because of the great difference in optical density between the air and the corneal material and because of the shape of the cornea, most of the refraction to incoming light rays takes place here. Light rays then pass through the pupil, and then onto the lens. A small amount of additional refraction takes place here as the light rays are "fine tuned" so that they focus on the retina.
Open-angle glaucoma - With this form of glaucoma, the loss of vision occurs so gradually it is rarely noticed. However, as eye damage increases, you will eventually find that you have lost a lot of areas of your peripheral vision, especially the field of vision near your nose. As larger areas of your peripheral vision fade, you may develop tunnel vision -- vision that has narrowed so you see only what is directly in front of you. If glaucoma is not treated, even this narrowed vision disappears into blindness. Once gone, areas of lost vision canno...
forces and are likely to be far more palatable to the local public whose support is ultimately the key in any counterinsurgency campaign, the advisory role of U.S. forces has become increasingly important. Strategic outcomes now hinge on advisor mission competence and success for at least two reasons. First, because America does not have enough ground forces to meet all security threats everywhere and must therefore rely upon the strategic leverage foreign troops provide; and second, because those forces have more legitimacy than do American troops who can be perceived as occupiers. “Strategic outcomes now hinge on advisor mission competence and success… because America does not have enough ground forces…[and]…because those forces have more legitimacy than do American
We use our ears for the hearing sense, and we use our eyes for vision.
In “The Ransom of Red Chief” by O. Henry, there are multiple examples of situational irony that has emotion. One example of situational irony is when Johnny is kidnapped by Bill and Sam, and he is supposed to be scared. Instead, Johnny likes being kidnapped because he does not have to go to
Visual perception plays a big part on how we perceive life. If we didn't have perception I don't know where we would be now.
This reflected light passes through the lens and falls on to the retina of the eye. Here, the light induces nerve impulses that travel through the optic nerve to the brain, where it makes an image of the object, and then that image is passed on to muscles and glands.The eye is well protected. It lies within a bony socket of the skull. The eyelids guard it in front. They blink an average of once every six seconds. This washes the eye with the salty secretion from the tear, or lachrymal, glands.