Red - red is the traditional color for maintaining night vision.
Green - green is now the preferred color for pilots and the military.
The green color is also great for retaining night vision, and it doesn’t erase the red markings on maps and charts.
Blue - many people like the blue because it is very easy on the eyes.
Blue appears to be a good reading light for elderly eyes. Elderly folks report that they can read under the blue light
for hours without eyestrain, compared to severe eyestrain in less than 30 minutes with incandescent lighting.
White - the most popular of the LED colors. It produces a soft white light, without harsh reflection, glare or shadows.