The causes of blurred vision can be categorized into physiological and pathological causes, such as visual fatigue, keratitis, cataract, and so on. 1. Physiological causes: If patients use their eyes excessively and suffer from visual fatigue, they may suffer from blurred vision, conjunctival congestion, eye soreness and other uncomfortable symptoms, which generally do not require special treatment and can be relieved after resting the eyes. 2. Pathologic causes (1) Keratitis: Bacterial, viral and other pathogenic infections can cause keratitis, the patient’s cornea is cloudy, which can cause blurred vision, photophobia, tearing and other uncomfortable symptoms. (2) Cataract: The clouding of the lens in cataract patients may cause different degrees of vision loss, and patients may have blurred vision at the initial stage. It is recommended that patients whose blurred vision is not relieved for a long period of time should consult a doctor in time to assess their condition and follow the doctor’s instructions for treatment.