The human eye, whose structure we will consider in the framework of this article, is not in vain compared to the mirror of the soul! Millions of odes, poems and legends have long been composed about their beauty. From century to century, the eyes are considered inextricably linked with the human soul. Even the most reputable scientists who know firsthand what our vision is, do not cease to be amazed at it to this day, calling this mechanism a real miracle of nature!
The human eye. Building
Our eyes are often compared to a camera. And indeed: there is also a casing (the cornea of the eye), and a lens (its lens), and a diaphragm (iris), and even a photosensitive film (the retina of the eye). The structure of the human eye, the drawing of which is attached, tells us the following.
Outwardly, our eyeball has an irregular shape of a ball. It is securely hidden in the corresponding eye sockets of the skull. The organ itself consists of auxiliary components (lacrimal organs, eyelids, conjunctiva, oculomotor muscles) andthe so-called optical apparatus (aqueous humor, cornea, vitreous body, lens, posterior and anterior chambers).
The human eye, whose structure is of the most complex nature, is covered in front by the lower and upper eyelids. Outside, they are covered with skin, and inside - with conjunctiva (the thinnest moist membrane). It is worth noting that it is the eyelids that contain special lacrimal glands to moisturize the mucous membrane of the eye.
Outer shell of the eye
It is the so-called sclera (white of the eye), the front part of which is visible through the transparent conjunctiva. The sclera passes into the cornea, without which no human eye can exist.
The structure of the cornea
This is the most convex part of our visual organ. Figuratively speaking, this is our "lens", our window to the world of visual senses!
Iris
This is a kind of diaphragm located behind the transparent cornea. Outwardly, this is a thin film that has a certain color (brown, gray, blue, green, etc.).
Pupil
There is a round black hole in its center. This is the pupil. It is through it that all the rays that fall on the retina pass. The lens is located in the region of the pupil. This is a kind of biconvex lens, which takes an active part in the accommodation of the eye.
The structure of the human retina
In its essence, it is very much like our brain. Speaking figuratively, this is a kind of window into the brain. Outwardly, it resembles a plate, consisting of 10 layers of cells. The retina of the eye istransparent. Of course, its most important layer is the photoreceptors, which include the so-called cones and rods.
Cones are responsible for the sharpness of our distance vision, and rods provide the periphery. It is worth noting that both cones and rods are located on the back of the retina. Therefore, the light that comes from outside must necessarily pass through other layers that stimulate them.
And finally
The structure of our eye is so complex, and the organ is so fragile and delicate, that the visual process itself is nothing short of a real miracle!
