Abstract: objects in nature reflect light with different light, dark and color under the irradiation of light. These light are focused on the retina through the refraction of cornea, lens and vitreous. The photoreceptor cells on the retina produce a series of electrochemical changes, convert light stimulation into nerve impulse, and transmit it to the occipital visual center of the brain through visual pathway, Complete visual function.
vision refers to the ability of human eye retina to distinguish images. Visual acuity is determined by the ability of the retina to distinguish images, When the refractive medium of the eye (such as cornea, lens, vitreous, etc.) becomes turbid or there is ametropia (including myopia, hyperopia, astigmatism, etc.) as well as retinopathy of fundus and damage of optic nerve conduction function, vision loss will occur. Structurally, the eye is similar to a camera, and the transparent cornea and lens with strong refractive power are equivalent to lenses; the pupil that can be reduced or opened according to light intensity is equivalent to aperture; it is rich in pigment and has the function of shading The dark box is composed of collateral membrane and retinal pigment epithelium; The neuroepithelial layer of the retina is equivalent to photosensitive film.
in nature, objects reflect light with different brightness and color under the irradiation of light. These light are focused on the retina through the refraction of cornea, lens and vitreous. The photoreceptor cells on the retina produce a series of electrochemical changes, convert light stimulation into nerve impulse, and transmit it to the occipital visual center of the brain through visual pathway, Complete visual function. In the above process, the pupil adjusts the luminous flux into the eyeball according to the intensity of light; The lens ensures that the light is accurately focused on the retina through regulation, so as to obtain a complete and clear monocular image. It is not enough for
to have clear monocular vision. In the process of human evolution, binocular vision is the highest visual function of human beings. It refers to the process that the cortical visual center analyzes the visual signals from both eyes and integrates them into a complete perceptual impression with three-dimensional feeling. It is with binocular vision that human beings can more accurately obtain the concepts of shape, orientation and distance of external objects, and correctly judge and adapt to the positional relationship between themselves and the objective environment. This perfection of visual cognition has played a very important role in human creative labor and evolution.
eye protection for daily eye use is very important, especially teenagers with heavy eye use burden and early aging people after the age of 40 are prone to visual fatigue. We must abide by three requirements and three don’t’s:
. First, pay attention to eye hygiene. Correct refractive abnormalities in time. Do not spend too much time reading or using the computer. Rest for 10 ~ 15 minutes every 30 to 40 minutes and look into the distance to relax your eyes.
second, we should pay attention to eye exercise. Doing eye exercises can make the blood unblocked, relax muscles and relieve fatigue. During ball games, when the eye follows the target, it is conducive to relax eye tension.
should pay attention to supplementary nutrition. Vitamin A and carotene are the main nutrients in human normal metabolism. Pay attention to replenishing water and eat more bean products, fish, milk, vegetables, tomatoes and fresh fruits to help protect your eyes.
one don’t read in dark places. Dark light will reduce contrast, prone to visual fatigue, and poor posture will also increase the burden on the eyes.
2 do not place eye drops frequently. Whether it is to relieve dry eyes or anti allergy and anti infection eye drops, you should follow the doctor’s advice, otherwise you may cause eye damage.
three do not use inferior lenses. The correction quality of inferior lenses is poor, and the decline of imaging quality will lead to visual fatigue; Poor quality sunglasses do not have strong UV blocking performance, and the enlarged pupil will lead to too much light entering the eye, causing fundus damage.