Scotopic vision refers to the human eye's ability to see in very low light, such as near-total darkness. This is primarily due to the rods in the retina, which are more sensitive to light than the cones (which enable color perception).
Features of scotopic vision:
- No color perception : Rods only detect brightness differences (shades of gray), so you see everything in black and white in the dark.
- High light sensitivity : The eye can perceive subtle differences in light, but details remain limited.
- Long adjustment time : It takes 20-30 minutes before you are completely used to the dark.
- Blue sensitivity : Rods are most sensitive to blue-green light (~507 nm), which explains why red lights are less disruptive in night environments (e.g. in cockpits or night vision goggles).
Scotopic vision is the opposite of photopic vision , which occurs in bright light and uses primarily the cones for color vision.