Читать книгу Essentials of Veterinary Ophthalmology - Kirk N. Gelatt - Страница 139

Temporal responsiveness of the retina has two aspects: motion detection and flicker detection. The retina responds to flashes of light as long as there is sufficient interval between two consecutive flashes, allowing the retina to recover from one response before the next flash is presented. However, as the frequency of these flashes increases, a point is reached at which the retina does not have enough time to recover between flashes and therefore it can no longer distinguish the individual flashes. At this point, which is termed the critical flicker frequency (CFF) or flicker fusion frequency, the eye perceives a steady light even though this light is made up of numerous flickers. There are separate CFFs for rod‐driven responses and signals generated from the different cone types, just as there are separate adaptation mechanisms for the rod and cone systems.