4.1 vision is around 300 degrees of myopia, and for people with strong compensatory capacity, it may be around 300-350 degrees of myopia. In people with weak compensatory capacity, about 250 degrees of myopia will also reduce vision to about 4.1. Whether it is 250 or 350 degrees of myopia, this degree needs to be corrected with glasses in daily life. Especially in young children, they will not be able to see the blackboard without glasses, and prolonged use of the adjusting power leading to eye fatigue may lead to a deepening of myopia. For adults, although the degree is more stable, this vision can affect normal life and can affect the safety of daily life, especially when driving. So both adults and children are recommended to wear glasses.