To identify the surface from which the retinoscopic reflex originates, retinoscopy was performed on 305 eyes of various ages with polarized and depolarized light. The discrepancy between retinoscopic and subjective refraction measures in the two conditions shows that two fundus reflective layers contribute to retinoscopy: a specularly reflecting layer presumably at the retina/vitreous interface and a diffusely reflecting layer near the pigment epithelium. In young eyes the retina/vitreous interface predominates; the other predominates in older eyes.