Shadows in the eyes when looking at things can be astigmatism or retinal or vitreous disease. Patients with astigmatism have an uneven density of refractive interstitium, so when imaging, it will appear that it cannot converge to a point on the retina, manifesting as a state of double vision. Especially at night the symptoms are more obvious, may look at lights and other objects appear shadow sense, can be optometrically corrected vision, glasses require the whole wearing. Not only can the shadow sense be improved, but also the visual acuity can be improved to improve the symptoms of visual fatigue. If the fixed shadow state in front of the eyes affects vision, it may be a more serious disease, such as vitreous hemorrhage or retinal hemorrhage, such as venous embolism retinal limited hemorrhage obscured, see things with a fixed shadow, or retinal detachment when there is a relative dark shadow in front of the eyes. Surgery is usually required for treatment, such as vitrectomy.