Presbyopia, or presbyopia, is a phenomenon in which the near vision is not sustained, and the lack of adjustment means that the near point gradually becomes farther and farther away, and the near object can be seen clearly after effort. As the eye ages, the ability to adjust gradually decreases, causing patients to have difficulty seeing near, so that in close work, they must add a convex lens in addition to their static refractive correction to have clear near vision, a phenomenon known as presbyopia. In addition to age, the occurrence and development of presbyopia is also related to the following factors: 1, refractive error farsighted eyes than nearsighted eyes appear presbyopia earlier; myopic wear frame glasses, due to the presence of 12-15mm distance from the corneal apex of the corrective negative lenses, reducing the need for the same reading distance adjustment, and wear corneal contact lenses myopic, due to corneal contact lenses worn in the cornea The corrected optical system is close to that of the ortho-optic eye. Therefore, wearing corneal contact lenses is earlier than wearing ordinary frame glasses to appear presbyopia. 2, the method of eye adjustment needs directly related to the working distance, therefore, engaged in close fine workers are prone to the symptoms of presbyopia, engaged in fine close work than those engaged in long-distance work to appear early presbyopia. 3.Physical quality Taller people with long arms have a longer working distance than shorter people with shorter arms and need less adjustment, so the latter have symptoms of presbyopia earlier. 4.Geographical location Because of the effect of temperature on the crystal, people living near the equator develop symptoms of presbyopia earlier. 5.The effect of medication Patients who take insulin anti-anxiety medication antidepressants, antipsychotics, antihistamines, antispasmodics and diuretics will develop presbyopia earlier because of the effect of medication on the ciliary muscle.