Preserving night vision at night is a common practice for tasks that are conducted in darkness. From military submarines and printing rooms to animal trackers and patrollers, red LED lamps are sometimes used to ease the transition and maintain clarity in low-light conditions.
Non-nocturnal animals rely on rhodopsin to facilitate night vision (not the same as night vision goggles). In low-light conditions, the chemical is produced rapidly by the merging of retinal and opsin molecules present in one’s eye. This process takes a short period to complete, resulting in temporary blindness for individuals coming from a bright environment to a dark one. After rhodopsin is produced, clarity is restored, which allows individuals to see with minimal lighting support.
Red light is used to preserve night vision, as the chemical is less sensitive to bands with long wavelength measurements. Exposure to red light does not cause reactions that reduce the creation of rhodopsin, which occurs when bright, white light (and other bright light colors) are present in the location.
RED LED Fixtures
There are several types of red LED lamps that can help preserve night vision in outdoor work sites, labs and during military projects. Red LED headlights are applicable for hunting, nighttime inspections and remote navigation. Control rooms and military submarines may utilize permanent red LED fixtures with a dual light mode for seamless transitions.
It is important to highlight that red lighting systems used to preserve night vision should be set at low light output settings. This is because high light output (regardless of the color) can decrease clarity in dark conditions.
Green and blue light is sometimes used to for increased distinction of colors and patterns at night. Applicable to map reading and control or briefing rooms, the colored lights help certain characteristics of the target stand out.