Flashes of light in the eye can be caused by posterior vitreous detachment, retinal detachment and vitreous clouding. 1. Posterior vitreous detachment: Posterior vitreous detachment refers to the separation of the posterior vitreous cortex from the inner surface of the retina, which pulls on the retina. This causes electrical stimulation of the retina, which results in a flashing sensation in the eye. 2. Retinal detachment: Retinal detachment is the separation of the neuroepithelial layer of the retina from the pigment epithelial layer. When retinal detachment occurs, it may be accompanied by a strong flashing sensation. The pre-symptoms of retinal detachment are usually a flashing sensation in the eyes, and you can go to the hospital for a funduscopic examination. 3. Vitreous clouding: Vitreous clouding refers to the presence of opacities in the vitreous. Vitreous clouding will be accompanied by the phenomenon of liquefaction, the eyeball will stimulate the retina after the shock, thus causing the eyes to flash. When patients experience flashes of light in their eyes, it is recommended that they go to the hospital to receive professional diagnosis and treatment from a doctor.