Searagen/Getty Images Submarines are fascinating pieces of military technology that play a major role in national defense, with nuclear submarines capable of staying underwater for months and navigating without GPS while they carry out stealth missions. If you’ve watched TV shows or movies featuring submarines, you’ve probably noticed that intense scenes are often bathed in red light. This isn’t just for dramatic effect; Submarines actually use red light because it’s easier on the eyes. To understand why submarines use red lights at night, it is important to know how the eyes work and what impact light and colors have on night vision. The eyes are made up of cones and rods. The cones are centrally located and are used for daytime and color vision, while the rods are intended to detect peripheral movement and threats, seeing in black and white. Human eyes can see light with wavelengths between 400 and 700 nanometers, interpreting it as colors ranging from violet to red. Since red light has the longest wavelength, the eye is less sensitive to it and adapts to it more easily than traditional white light. As such, red light is also helpful in maximizing your night vision. After about 20 minutes of low light, the eyes begin to produce a chemical called rhodopsin that activates the rods. It takes another 20 to 40 minutes for night vision to really take hold, but even a small amount of bright light causes rhodopsin to break down, restarting the whole process. Dim red light doesn’t have the same impact, allowing your night vision to trigger (and persist) as intended. Red light is more useful than you think Andreonegin/Getty Images Since red light is less harsh on the eyes and does not interfere with the activation of night vision, it is ideal for underwater use. It illuminates the space enough for the crew to see what they’re doing while helping those on board distinguish between day and night underwater without daylight. This is important for maintaining healthy sleep patterns and avoiding interruptions to the body’s natural circadian rhythm; Different colors of light impact the circadian rhythm, and red has little to no impact. Studies have shown positive signs that red light may help improve sleep quality, although more research needs to be done. At the very least, it doesn’t have the same negative impact as blue and white light, making it healthier to use before bed. Red light also has many other applications beyond submarines. You may also have heard about red light therapy from the many social media influencers and celebrities who swear by it for everything from anti-aging to hair growth. There is scientific and historical data to support these claims, although the results are generally less dramatic than users expect. Additionally, red light has environmental benefits. Places like Denmark have installed red street lights that are less aggressive to local bat species, as traditional street lights have been shown to impact their behavior, sometimes putting them in danger. Other places have installed red lights to reduce the impact of traditional white street lights on turtles. These creative, science-based solutions are a great use of the red light that helps the local ecosystem while providing visibility for drivers. Post navigation The transparent tech trend of the 90s is making a comeback Scientists are using internet cables for something they weren’t designed for
Searagen/Getty Images Submarines are fascinating pieces of military technology that play a major role in national defense, with nuclear submarines capable of staying underwater for months and navigating without GPS while they carry out stealth missions. If you’ve watched TV shows or movies featuring submarines, you’ve probably noticed that intense scenes are often bathed in red light. This isn’t just for dramatic effect; Submarines actually use red light because it’s easier on the eyes. To understand why submarines use red lights at night, it is important to know how the eyes work and what impact light and colors have on night vision. The eyes are made up of cones and rods. The cones are centrally located and are used for daytime and color vision, while the rods are intended to detect peripheral movement and threats, seeing in black and white. Human eyes can see light with wavelengths between 400 and 700 nanometers, interpreting it as colors ranging from violet to red. Since red light has the longest wavelength, the eye is less sensitive to it and adapts to it more easily than traditional white light. As such, red light is also helpful in maximizing your night vision. After about 20 minutes of low light, the eyes begin to produce a chemical called rhodopsin that activates the rods. It takes another 20 to 40 minutes for night vision to really take hold, but even a small amount of bright light causes rhodopsin to break down, restarting the whole process. Dim red light doesn’t have the same impact, allowing your night vision to trigger (and persist) as intended. Red light is more useful than you think Andreonegin/Getty Images Since red light is less harsh on the eyes and does not interfere with the activation of night vision, it is ideal for underwater use. It illuminates the space enough for the crew to see what they’re doing while helping those on board distinguish between day and night underwater without daylight. This is important for maintaining healthy sleep patterns and avoiding interruptions to the body’s natural circadian rhythm; Different colors of light impact the circadian rhythm, and red has little to no impact. Studies have shown positive signs that red light may help improve sleep quality, although more research needs to be done. At the very least, it doesn’t have the same negative impact as blue and white light, making it healthier to use before bed. Red light also has many other applications beyond submarines. You may also have heard about red light therapy from the many social media influencers and celebrities who swear by it for everything from anti-aging to hair growth. There is scientific and historical data to support these claims, although the results are generally less dramatic than users expect. Additionally, red light has environmental benefits. Places like Denmark have installed red street lights that are less aggressive to local bat species, as traditional street lights have been shown to impact their behavior, sometimes putting them in danger. Other places have installed red lights to reduce the impact of traditional white street lights on turtles. These creative, science-based solutions are a great use of the red light that helps the local ecosystem while providing visibility for drivers.
