Laser Beams Come In Different Colors

Red laser light was the first visible color that was produced by a solid state, laser diode.  Other colors like green and blue are now available and have different benefits including apparent increases in brightness with the same amount projection power. Color centric functions like safety exclusion zones, improvements in outdoor visibility and use are now available.

Since eye visible laser beams and lines are designed to be detected by the human eye, the color itself can be informational.  Red and green colors imply stop and go while blue is the new safety warning color that surrounds dangerous machinery, exclusion zones around forklifts and overhead cranes.  The green laser color is a wavelength that is more visible to the human eye by a factor of almost 10 times as much compared to the red and blue wavelengths.  So green laser dots and lines are used more in applications that have a higher ambient back ground light like overhead lights and sunlight.  Night time, low light conditions, underwater lasers and underground lasers for coal mines favor the red and green wavelengths.  Remember, too much brilliance is not useful to human users.  Therefore, brightness is an application specific feature and a design criteria.