Читать книгу Essentials of Veterinary Ophthalmology - Kirk N. Gelatt - Страница 123

The outermost cells in the neural retina are the photoreceptors, which are divided into two classes: rods and cones. Rods and cones differ from each other in their morphology, function, and retinal distribution. Functionally, cone systems are characterized by high resolution of fine details, rapid responses, color perception, and low sensitivity to small fluctuations in light intensity. Rod systems are characterized by poor visual resolution and no color perception, but they are extremely sensitive to minute changes in light levels and detection of motion. Therefore, cones are particularly suitable for daylight photopic vision, whereas rods contribute mostly to dim‐light scotopic vision (Figure 2.14).