Sclerotic:- The first part of the eye is Sclerotic. Sclerotic is the outer coating of the eye . Which is white in colour, that protects the interior of the eye and provide the shape of the eye. Cornea:- The first part of the Sclerotic is transparent to light is termed as Cornea The light coming from an object enter the eye through Cornea.
Iris:- Iris is just at the back of the cornea this control the size of pupil. It acts like a shutter of a photographic camera and allow the regulated amount of light to enter the eye. Eye lens:- Eye lenns is a double convex lenns with the help of which image image is formerd at retina by refraction of light .
Ciliary Muscles:-The eye lens is held by ciliary muscles. Ciliary muscles is help the eye lens to change the focal length. Pupil:-At the center of iris there is a whole thouugh which light falls on the lens, which is called pupil.
A transparent fluid fills the space between the cornea and the eye lens. This fluid is called the aqueous humour. The eye also has a blind spot, the region containing the optic nerve, which is not sensitive to light. Images formed in the blind spot are not visible. A transparent jelly called the vitreous humour fills the space between the eye lens and the retina.
Made up of light sensitive cell located at the back of the eye lens, the retina serves as the eyeas screen. It is here that images are formed before being sent to the brain by the optic nerve. The optical system of the eyeas principal axis is the dotted line XY axis.
The yellow spot is the most light-sensitive part of the retina. It lies on the optical axis. Eye lids are primarily used to protect the eye from external particles and limit the amount of light that falls on the eyes.
The human eye can focus on various objects at various distances. This is done by altering the power of the lens and is called the power of accommodation of the eye. Ciliary muscles also play a role in this ability as they change both the focal length and the curvature of the eye. This helps form clear retinal images of objects at various distances despite the fixed nature of the distance between the optical center of the lens and the retina.
The eye can have various defects. One of these is Myopia. Myopia is present when a person cannot see distant objects clearly. Close objects, however, remain clear. Another defect is known as Hypermetropia which is the opposite. Someone with Hypermetropia can see distant objects clearly but struggle focusing on close objects.
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