There are many causes of amblyopia, including strabismus, refractive error and form deprivation, as follows: 1. If a patient with strabismus keeps a monocular gaze for a long time and the other eye is skewed outward, the skewed eye does not get a gaze or enough light stimulation, leading to amblyopia; 2. If the refractive error is not corrected in time, it will also lead to amblyopia; 3. Formal deprivation factors mainly include congenital cataract or congenital ptosis, after the disease is blocked to the vision, the macula can not receive enough light stimulation, it can not fully develop, resulting in amblyopia.