anatomy of the eye model

The human eye is a remarkably complex anatomical device, showing the architectural wonders of the human body. As a camera, the eye is able to refract light and produce a sharp image, to stimulate and activate the chance to see the neuronal responses. In Lesson 6, we will focus on the physics of view. We are to use our understanding of the formation of the refractive and visual understanding of the means by which the human eye creates images of distant and near objects. Furthermore, we will examine some of the most common vision problems affecting the people and the common solutions to these problems. When we go through Lesson 6, we will our understanding of refractive lenses and to apply physical view.

The eye is an eyeball opaque substantially filled with a liquid such as water. In the front of the eyeball, it is known as a transparent cornea aperture. The cornea is a thin membrane, which has a refractive index of about 1.38. The cornea has enters the dual purpose of protecting the eyes and refraction of light in the eye. After light passes through the cornea, a part of it through an opening, such as the pupil known. Instead of an actual part of the anatomy of the eye, the pupil is more than one opening. The pupil is the black part in the center of the eyeball. His black appearance is due to the fact that light enter the pupil in the eye is absorbed in the retina of the eye (and elsewhere) and not attributed. Therefore, as seen in the opening of the other students, no light coming from his community and come to your eyes; Black student then searches.

As the opening of a camera, the aperture size of the pupil be adjusted by dilation of the iris. The iris is the colored part of the eye - for some people still blue and brown for other (and so on); is a membrane to stretch able and reduce the size of the opening is. In situations of bright light, the iris size is adjusted to reduce the opening of the pupil and to limit the amount of light entering the eye. In low light situations, the shutter is set to maximize the opening size of the pupils and increase the amount of light entering the eye.

Light passing through the opening of the pupil, enters the lens. The lens is made from layers of fiber material with a refractive index of about 1.40. In contrast to a camera lens, the lens of the eye, to be able to change their shape, and serves to sharpen the vision process therefore. Lens attached to the ciliary muscles. These muscles relax and contract to change the shape of the lens. Produce by careful adjustment of the lens shape, the ciliary muscle of the eye help in the critical task of an image on the back of the eyeball.

The inner surface of the eye known as the retina. The retina contains the rods and cones, which serve the task of capturing the intensity and frequency of the incoming light. Adult eye normally equipped with up to 120 million rods, which detect the intensity of light and about 6 million cones to detect the light frequency. These rods and cones send nerve impulses to the brain. Nerve impulses travel through a network of nerve cells. There is a maximum of one million nerve pathways of rods and cones in the brain. This network comprises neurons together to form the optic nerve in the back of the eyeball.

Each of the eye plays a different role in what people see. The ultimate goal of an anatomy that is to man in order to focus images on the back of the retina. This problem is discussed in the next part of the lesson six.