Gourd baby vs Naruto pirates

Chapter 465 The Secret of the Eyes

Chapter 465 The Secret of the Eyes

After Erwa's clairvoyance has this pair of sunglasses, he is like a tiger with wings added!He can see clearly many places that clairvoyance can see blurredly!

This pair of sunglasses helped Erwa overcome the effect of strong light!

But Phoenix Goddess said: "Just overcoming the glare is not enough. After all, the eyes still have many secrets, especially your clairvoyance is the secret of the secrets of the eyes!"

Erwa became very interested, and he said, "Then what is the secret of my eyes?"

The Phoenix Goddess explained: "The eye is the visual organ of humans and animals. It is composed of the eyeball and the appendages of the eye, and the main part is the eyeball.

Eyes are the most important organ in human senses, and about 80% of the knowledge in the brain is acquired through eyes.Eyes are used for reading and recognizing characters, looking at pictures and paintings, seeing people, and enjoying beautiful scenery.The eyes can distinguish different colors and brightness of light, and convert this information into nerve signals and send them to the brain.

The human eye is the benchmark for the magnification of the telescope, that is to say, the magnification is 1, and the caliber is the size of the pupil of the human eye. It changes with the light intensity, and generally fluctuates between 2 and 7 mm. "

Erwa said: "In other words, the eyes are also a light source that can emit light! What it can see is where the light can shine."

Goddess Phoenix feels that Erwa has a very rich imagination, and she especially likes Erwa's explanation.

"What you said is right, it can be understood in this way. But I can also go a little deeper. The eye changes the focal length of the lens by adjusting the degree of curvature of the lens to obtain an inverted, reduced real image. The farthest point that the eye can see It is called adjusting the far point. The far point that the emmetropic eye can see is extremely far away; the nearest point that the eye can see is called the adjusting near point, and the distance between the two points is called the adjusting range. The near point of the normal eye is at the distance from the eye About 10 centimeters away."

Erwa questioned: "Then my clairvoyance is not a normal eye, what are those eyes made of?"

The human eye is approximately spherical and located in the orbit.The front end protrudes 12~14mm outside the orbit and is protected by the eyelid.The eyeball includes the wall of the eyeball, the inner cavity and contents of the eye, nerves, blood vessels and other tissues.

The wall of the eyeball is divided into three layers: outer, middle, and inner.The outer layer is composed of the cornea and sclera, also known as the fibrous layer.The first 1/6 is the transparent cornea, and the remaining 5/6 is the white sclera, commonly known as the "white of the eye".The outer layer of the eyeball maintains the shape of the eyeball and protects the tissues inside the eye.The cornea is the most sentinel entrance for receiving information.The cornea is the transparent part of the front of the eye, through which light enters the eye and transmits light into a transparent wafer.The cornea is slightly oval and slightly protruding.The cornea is rich in nerves and has a keen sense.Therefore, in addition to being the main structure for light entering the eye and refraction imaging, the cornea also plays a protective role and is an important part of measuring human perception.The sclera is a dense collagen fiber structure, opaque, milky white, and tough in texture.The middle layer, also known as the uvea, is rich in pigment and blood vessels, including the iris, ciliary body, and choroid.Iris: circular, in the front part of the uvea, in front of the lens, with radial folds called texture, and the surface contains uneven recesses.People of different races have different iris colors.There is a 2.5~4mm round hole in the center, which is called the pupil.The ciliary body is connected to the root of the iris in front, the choroid in the back, the sclera on the outside, and the equator of the lens on the inside through the suspensory ligament.The choroid is located between the sclera and the retina.The blood circulation of the choroid nourishes the outer layer of the retina, and the rich pigment it contains acts as a darkroom.The inner layer is the retina, which is a transparent membrane and the first stop for the transmission of nerve information formed by vision.It has a fine network structure and rich metabolic and physiological functions.The end point of the visual axis of the retina is the fovea of ​​the macula.The macular area is a special area with the sharpest vision on the retina, with a diameter of about 1-3 mm, and a small concave in the center, the fovea.About 3mm from the nasal side of the macula, there is a light red area with a diameter of 1.5mm. It is the optic disc, also known as the optic nerve. The dark area is called the physiological blind spot.

Cornea introduction: The cornea is divided into five layers, from front to back: epithelial cell layer, Bowman's layer, stroma layer, Bowman's layer, and endothelial cell layer. Composed of 50-10 layers of cells, the corneal peripheral epithelium thickens, and the cells increase to 5-6 layers.In the past, it was believed that the Bowman's membrane was a special layer of membrane, and electron microscope observation showed that the membrane was mainly composed of collagen fibers.The stroma is composed of collagen fibers, about 8um thick, accounting for 10% of the thickness of the entire cornea. The parenchyma contains 500-90 lamellar layers, which overlap each other.The lamina is parallel to the surface of the cornea, and the lamellae are also parallel to each other, which ensures the transparency of the cornea.Descemet's membrane is the basement membrane of corneal endothelial cells, which is easily separated from the adjacent stroma and endothelial cells. The descemet's membrane is strong and resistant to chemical substances and pathological damage.Endothelial cells are a single layer of cells consisting of about 200 hexagonal cells. The cells are 250um high and 500000-5um wide. The nucleus is located in the center of the cell and is oval in shape with a diameter of about 18um.

The cornea is rich in sensory nerves, mainly from the ophthalmic branch of the trigeminal nerve to the cornea through the ciliary nerve.

If the eyes are compared to a camera, the cornea is the lens of the camera, and the eyelids and tears are the devices that protect the "lens".When we are unconscious, the eyelids will blink, and every time we blink, tears will cover the surface of the cornea with a thin tear film to protect the "lens".

Since the cornea is transparent, there are no blood vessels on it.Therefore, the cornea mainly obtains nutrients from the tears. If the nutrients contained in the tears are not sufficient, the cornea will become dry and the transparency will decrease.The cornea also gets oxygen from the air, so many people wake up with dry eyes.

The inner cavity of the eye includes the anterior chamber, posterior chamber, and vitreous cavity.The contents of the eye include the aqueous humor, lens, and vitreous.All three are transparent, and together with the cornea, they are called the refractive medium.

Aqueous humor is produced by the ciliary process, nourishes the cornea, crystal and vitreous body, and maintains intraocular pressure.The lens is an elastic transparent body, shaped like a biconvex lens, located behind the iris, pupil, and in front of the vitreous.The vitreous body is a transparent colloid that fills the cavity of the posterior 4/5 of the eyeball.The main ingredient is water.The vitreous has a refractive effect and can also support the retina.

The optic nerve is part of the central nervous system.The visual information obtained by the retina is transmitted to the brain through the optic nerve.The visual pathway refers to the entire nerve impulse transmission path from the retina receiving visual information to the visual cortex of the brain to form vision.

After hearing a lot of knowledge about eyes, Erwa was a little confused.

The Phoenix Goddess told Erwa, "Your clairvoyance surpasses them, and it is a special eye that can see all directions."

(End of this chapter)