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Asked by: Adele Videla
medical health eye and vision conditionsWhy do we use red light at night?
Also, why is red light used in the dark?
The human eye is less sensitive to longer wavelengths, so red light is chosen to preserve the night vision of the crew while still allowing them to still see their instrument panels. Submarines switch to red light when it's dark outside and crew members need to use the periscope or go on watch duty.
Herein, what does it mean when you have red lights on at night?
the red lights are used at night because when you turn them on, you can see around, but when you turn them back off, you don't have to re-acclimate to the low light. Bugs are genetically attracted to white light because they use the moon to "navigate" and white porch lights disrupt this navigation system.
That is why you see the pupils change size when light conditions change. Red light, however, does not trigger pupil contraction as much as other colors of light, making a red flashlight ideal for enjoying the night landscape. Light-sensitive cells in the retina at the back of our eye allow us to see.