What is normal vision? What time is zero?

Normal visual acuity is a degree, and my eyesight is about two or so nearsighted.

1. Central vision: that is, the visual acuity determined by people usually looking at the eye chart, including distance vision and near vision. Patients with hyperopia present with better distance vision than near vision; The opposite is true for patients with myopia.

People with astigmatism have poor distance and near vision. When the near and distance visual acuity is above or above, the central visual acuity is normal.

2. Peripheral vision: When the eyes are fixed on a certain target, the range that can be seen in the non-fixation area is large or small, which is called peripheral vision, which is often referred to as "residual vision". The range of peripheral vision in a normal person is quite large, up to 90 degrees on both sides, 60 degrees above and 75 degrees below.

Patients with myopia and night blindness have poor peripheral vision, and some fundus diseases can also cause peripheral vision loss.

3. Stereopsis: Stereopsis is a kind of superlative vision, that is, on the basis of normal vision in the center of the two eyes, through the harmony of the two hemispheres of the brain, you can feel the distance relationship between objects in space. Some people have normal central vision but abnormal stereopsis, which is medically called stereopopia.

1. A person's normal vision is generally normal vision, and according to the standard eye chart, it is left and right.

2. Visual acuity refers to the ability of the retina to distinguish images. However, when the refractive medium of the eye (such as cornea, lens, vitreous, etc.) becomes cloudy or there is refractive error (including myopia, farsightedness, astigmatism, etc.), the vision of the eye with good retinal function will still decrease. The refractive medium of the eye is cloudy and can be surgically corrected, while the refractive error needs to be corrected with a lens.

The normal human eye vision is above.

The most important feature of the human eye is the ability to recognize details, which is often expressed in terms of viewing angle resolution, and is called visual acuity. The standard for expressing visual acuity is the opening angle of the smallest character that the human eye can recognize, and the normal human eye has above the visual acuity.

The visual acuity usually refers to the minimum divisible visual acuity of the eye rather than the minimum visible visual acuity, so the eye chart reflects the smallest viewing angle of the two points of the examinee's gaze at the target, that is, the minimum divisible visual acuity, or 1' viewing angle visual acuity, which can represent the best visual function of the examinee.

Visual acuity is divided into central visual acuity and peripheral visual acuity. Central vision reflects the function of the fovea of the macular part of the retina, and is the ability of the human eye to recognize the shape and size of external objects. Peripheral vision is also called peripheral vision.

The so-called visual acuity refers to distance vision and is central vision, static vision, which reflects the function of the macula, the most sensitive part of the retina, and distance vision examination is usually performed with an eye chart.

If the vision is yes, then it is considered normal vision! And this vision has no prescription! You just need to do a good job of daily protection!

1. Pay attention to the time you spend with your eyes.

Children's eye development is not perfect, the ability to work is low, every time you read or write for an hour, you should let the child go to outdoor activities, do games, look into the distance, or observe the flowers and trees, so that the tense eye muscles are relaxed, eliminate fatigue. In addition, it is necessary to make the child's life regular, have enough sleep, and make the eyes have enough rest.

2. Pay attention to the light of your eyes.

Do not allow your child to read or write in dark light or sunlight. If a 25-watt light bulb is used indoors at night, the distance between the book and the bulb should be within 1 meter. If you use a stool to starve for a 60-watt light bulb, the distance between the book and the bulb should be 1 2 meters.

Cloudy days, dusk, weak light in the moonlight, and strong light in the sun are not suitable for reading and writing. When watching TV, it is necessary to maintain a suitable distance, which should generally be 5 7 times the diagonal length of the phosphor screen. The time to watch TV should not exceed 2 hours at a time.

3. Pay attention to eye exercise.

Physical exercise can enhance blood circulation and metabolism, supply more nutrients to the eyes, and enhance the resistance of the eyes, which is an indirect exercise for the eyes. The direct exercise is eye exercises, which are based on the scientific methods of massage, massage, acupuncture and moxibustion acupuncture points in Chinese medicine, combined with the protection of eyesight. Parents should learn the basic knowledge of eye exercises, give specific guidance and often urge their children to do eye exercises, and persevere.

4. Pay attention to eye nutrition.

In order to protect children's eyes, children can eat more carrots, animal liver, lean meat, to supplement vitamin A, or regularly supplement the comprehensive nutrition of the eyes with Leyan vision nutrients, and at the same time, it is also necessary to appropriately consume millet, tofu, animal liver and other supplements of vitamin B2, so as to avoid night blindness, corneal malacia, red eyes, dry itching and other symptoms. Eating too much sugar will harm your child's eyesight, so your child's sugar intake should be controlled.

5. Pay attention to regular inspections.

Regular check-ups are due to the fact that children's eye structure, binocular visual function, and intelligence are still in the process of continuous development after birth, and the content of the examination is different at different ages. The usual age of ophthalmologic examination is generally 2-7 days after birth, 42 days after birth, 3 months, 6 months, and 1 year of age, and then once a year. In this way, the problem can be detected early and corrected early, instead of waiting until the vision has deteriorated and there is a vision problem before going for a check-up.

The normal vision of the eye is 0 degrees, and once it exceeds zero degrees, it is the range of myopia, which represents myopia.

Myopia, the name of a disease in traditional Chinese medicine. It is the eye in a state of accommodative relaxation, and the focus of parallel light rays refracted through the refractive system of the eye falls in front of the retina. Ancient medical books have long known about this disease, called eye can not farsighted, also known as can land cover near and distant disease, to the "eye Jing Dacheng" began to call myopia.

Born from congenital conditions, those with a higher degree of myopia are also known as myopia. The occurrence of myopia is related to many factors such as genetics, development, and environment, but the exact pathogenesis is still being studied.

If the visual acuity is lower than normal, it is usually considered that there may be refractive error and amblyopia, and it is necessary to go to the hospital for optometry. Visual acuity refers to the ability of the retina to distinguish images. However, when the refractive medium of the eye (such as keratinal membrane, lens, vitreous, etc.) becomes cloudy or has refractive errors (including myopia, farsightedness, astigmatism, etc.), vision will still decline even if the retina is well-functioning.

There is no direct relationship between the amount of visual acuity and the degree of myopia, if the original vision is normal or yes, and now the vision is lower or it may be myopia. If the original vision was or so on, now the vision is only or may be myopia. There are no other eye diseases, and the loss of vision may be myopia, of course, it may also be astigmatism or farsightedness.

As a result, decreased vision requires ophthalmologic consultation and exclusion of ocular organic disease.

The normal vision of ordinary people is, that is, what people say, belongs to normal vision, and generally less than the following is basically myopia, this situation is also more common in life, some serious can also be seen from the above lens, the thicker the lens, the higher its power, if the more serious is not able to take off the glasses.

Most of the people with myopia are teenagers, and whether they are myopic or not needs to be judged by doctors. Generally, less than 300 degrees belong to mild myopia, 300-600 degrees belong to moderate myopia, more than 600 degrees belong to high myopia, and more than 1000 degrees belong to ultra-high myopia. There are several situations in which adolescents may be found to be nearsighted:

Generally, the teacher finds that his eyesight has deteriorated and cannot see clearly, and reports it to his parents; Teenagers take the initiative to report blurred vision to their parents; A school physical examination found that his eyesight was not up to standard.

It's a good place, I haven't been anywhere else, and the endless stream of people who consult every day proves that this place is the right choice.