EYE  ANATOMY  AND  FUNCTION:

 

 

anatomy of eye



The eye is the most important sensory part of the body. Humans can visualize every object through the eye and it helps to deduct light perception, color, and depth of perception. The eye is an organ similar just like the action camera, the function of the eye is to focus on an object, make an image, and deduct all its qualities.

It is interesting to understand the shape and function of the human eye. It is a spherical ball-shaped organ, which is filled with some fluid. It’s a sense organ, that focuses the target image and transmits it to the brain. Light passes through its transparent layer and activates the receptor cells on the retina, which turn impulses to the brain through the optic nerve.

 

EYE ANATOMY:

 

 

eye anatomy



It consists of the following parts:

SCLERA:

It’s a protective outer covering white layer, surrounding the iris, and is called the sclera.

CORNEA:

It’s a transparent front layer of the sclera called the cornea. light crosses the eye and focuses the object sharp and clarifies. During laser surgery, we reshape the cornea and improve its focus features.

IRIS:

It is a ring-like structure and a dark-colored muscular tissue. It’s located behind the cornea and is called Iris. The color of the eye is mainly due to the color of the iris. It helps to regulate the light entering the eye.

The main function is that.

When there is a sharp and bright light, it helps the pupil to close, to focus the image; when there is dark light, it helps the pupil to open and widen the image. The main thing is that iris adjustment maintains human vision in light and dark.

PUPIL:

There is a small dark center opening in the iris called the pupil. Iris controlled its size and adjusted it according to the light, which means it became smaller in bright light and wider wide in dark light. It also controls the quantity of light.

LENS:

There is a transparent structure behind the pupil called Lens. It focuses the light rays onto the retina with the help of ciliary muscles. It becomes small, to focus on the far object and it becomes large, to sharpen the near object.

It can be replaced by intraocular lenses during cataract surgery.

RETINA:

Its transparent sensitive layer covered the back of the eye. It has numerous nerve cells. When light touches the retina, it generates an electrical impulse and is transmitted to the brain through the optic nerve.

OPTIC NERVE:

There are two types of optic nerve rods and cones.

1.      Rods:

      It is a type of optic nerve cell, that is most complex to dim light. It supports peripheral vision.

2.      Cones: 

      It is another type of optic nerve cell, that is most complex to bright light. It supports the color and central vision.

There is a junction of the retina and optic nerve, which has no sensory nerve cells. There is no vision at this point and it is called a blind spot.

The optic nerve is a bundle of several nerve fibers that transfer visual images from the retina to the brain. Mainly it’s a connector between the eye and the brain.

The function of the retina is to focus images upside down and the brain is to combine the images Actually, the retina catches the image in the reversal form and the brain reverses the image and maintains the correct image due to the optic nerve. This process is the same as the convex lens.

That’s why Glaucoma is the most common eye disease due to optic nerve damage.

VITREOUS HUMOR:

It is the glutinous clear fluid, which fills the central cavity of the eye.

CILIARY BODY:

The ciliary body is located behind the iris, it has a muscle that focuses on the lens.

CHOROID:

There is a layer in the back of the eye, between the retina and the sclera, and it contains a group of blood vessels called the choroid.

MUSCLES:

An eye contains 6 muscles and its function is to support different torques and tensions, which control all movements of the eyes. Names of these 6 muscles are.

  • Medial rectus
  • Lateral rectus
  • Superior rectus
  • Inferior rectus
  • Inferior oblique
  • Superior oblique.

 

FUNCTION OF EYE:

 

 

function of eye



Light crosses the front of the eye from the cornea to the lens. The lens and cornea help to target and focus the light onto the retina of the eye. The retina cells engage and transfer the light into electrical impulses, which transfer through the optic nerve to the brain.

The eye work is the same as the camera work. The camera shutter opens and closes, according to the amount of light, required to focus and expose the image in the back of the camera. the same process happened in the eye. The pupil and iris control the light; how much light is needed to focus and sharpen the image in the back of the eye. When there is darkness, the pupil becomes large, allowing light to enter the eye. When there is light, the pupil constricts in size and restricts the amount of light, that enters the eye.

The lens helps us to focus the image and sharpen the image as per requirement, day and night. Contact lenses, glasses, and artificial lenses help humans to clear image more, who has a need to sharpen the image due to lens problems.