Why do you need to wear a drop-down mirror for visual training? Are there any special effects?

According to the patient's refractive condition, the focus reducer gives a concave lens lower than the current diopter. Combined with the unique deflection function of the prism, the gaze distance moves to a far distance, and then through the visual nerve memory, the telephoto ability is enhanced and the myopia degree is reduced. So diopter can not only see clearly, but also reduce myopia.