Photoreceptors

Photoreceptors are very special sensory neurons that can convert incoming light into an electrical signal that can be carried to the brain to, ultimately, create conscious vision.

Photoreceptors are divided into two main types based on their specific shape, size, and light-detecting abilities:

• Rods: bigger and longer, rods sense the presence/absence of light in the visible range and are highly sensitive so they can function in dim light.
• Cones: smaller and shorter, cone cells respond to light of a more specific wavelength and so provide color vision. There are three types of cones in humans, which sense red, green, or blue light.