The blurred vision of patients may be affected by physiological factors on the one hand, and may be caused by pathological factors on the other hand, such as refractive error, ocular inflammation, cataract and other diseases. 1. Physiological factors: If patients often stay up late, look at electronic products such as cell phones or computers, they may suffer from visual fatigue due to poor rest, which may lead to the symptoms of blurred vision. 2. Pathological factors (1) Refractive error: Refractive error includes myopia, hyperopia and astigmatism, in which parallel light rays cannot fall on the retina normally after refraction by the refractive system of the eye, and thus patients may experience blurred vision. (2) Ocular inflammation: patients with ocular inflammation, such as keratitis, scleritis, iritis, etc., due to the inflammatory reaction leading to eye congestion, eye secretions increase, patients may experience blurred vision. (3) Cataract: cataract is common in the elderly, the lens has a refractive effect, the density of the lens increases when it is cloudy, and less light passes through the lens, so the patient will have blurred vision; It is recommended that patients whose blurred seeing is not relieved for a long period of time should consult a doctor in time to assess their condition, and under the guidance of the doctor for examination and treatment.