Alternate eyes

Alternate vision: The lens is designed to move on the cornea in the direction of the gaze, so that the far and near areas can be almost completely covered on the pupil. Long-distance or short-distance vision can alternate the line of sight through different areas of the pupil. Alternate vision occurs in cases where both eyes have better vision. Both eyes can focus on the target, and the two eyes can be used alternately. Another case is that the child has nearsightedness in one eye, and emmetropia or mild hyperopia in the other eye, and will look involuntarily. The near-sighted eye is used for near-term and the front-sighted or far-sighted eye is used for far-sightedness, forming the rule of alternately using both eyes. Although only one eye is used at a time, since far-sighted, adjustment and assembly are not used when looking at near-sight, so there may be no symptom. The patient only looked into the distance with one eye and the near eye with one eye. Over a long period of time, the visual function will be greatly reduced, forming "alternating vision", destroying the normal three-dimensional vision, and severely causing strabismus. It is a clinical symptom of refractive error. Refractive error refers to the diopters of both eyes. If the degree difference is more than 2.00 D, symptoms usually occur due to difficulty in fusion. Because the eye's adjustment activities are simultaneous in both eyes, those with high refractive errors often have blurred vision, which is likely to cause amblyopia, and those with high refractive errors who have high degrees of vision become amblyopia. The refractive errors are mostly congenital. , And often combined with varying degrees of facial development asymmetry. The refractive status and degree of the two eyes are different. Generally, the difference between the two eyes is more than 250 degrees, which is called refractive error.