Image receivers, also known as retinal receptors, are specialized cells located in the retina of the eye. They are responsible for converting light into electrical signals that are then sent to the brain, allowing us to see. The two main types of image receivers are retinae and retinas. Retinae are light-sensitive cells located in the inner layer of the retina, while retinas are light-sensitive cells located in the outer layer of the retina. Both types of cells are essential for vision.