If the eyes suddenly appear to see things farther away, the following two causes are common: 1, visual fatigue: such as adolescents stay up late, excessive use of computers, cell phones appear ciliary muscle spasm, vision will suddenly decline, see things smaller, unclear, see things especially far. If there is no underlying lesion or fundus problem, after sufficient rest and using eye drops to relieve fatigue, the situation of seeing things farther and smaller will be gradually relieved. 2. Retinal lesion: There is also a part of sudden vision loss mainly considering fundus retinal lesions, such as common central plasmacytoid exudative retinopathy and macular edema bulge will cause seeing things smaller, rounder and distorted. Patients need to be diagnosed by detailed fundus examination.