There are several possibilities for blurred vision in the left eye. If the young person is the most common may be refractive problems, commonly myopia and astigmatism cause blurred vision, it is necessary to go to the hospital, have an optometric examination and correct the vision to see if it can be improved. If the vision can be corrected without improvement, the fundus and other conditions need to be checked to rule out ophthalmic disease problems. If an elderly person sees things blurred, it is commonly a cataract. If seeing is persistently blurred or has a gradual process, it is likely to be a cataract, and a timely visit to the hospital is needed to check the condition of the crystal and rule out cataract. If it is a cataract that is not obvious, the same optometric examination should be performed and the cause can be clarified.