What is the difference between Red and Green Beam Laser Levels? Red beam laser levels have been around for quite a number of years now, in recent years green beam laser levels have become available. But what is the difference and which color laser is best for you?
Green beam lasers operate at a different light frequency to red and they generally have a greater class 3r (3a) output wattage 5mW compared to a standard class 2 red beam of under 1mW, note you can get class 3r (3a) red beam also with a sub 5mW output. So that is the technical difference but what is the real work job site difference? Green beam lasers appear clearer and more visible in low light conditions such as indoors than a similar power output red beam and this is due to the human eye being more sensitive to the color green compared to red. So in a nutshell Green appears brighter and clearer visibly.
Outdoors in full sun you cannot realistically see either red or green beam more than a handful of meters, for reliable outdoor use you need an electronic laser receiver to see the laser for you, wether it be a rotary laser or a line laser.
So which color laser is best for you? the answer is quite simple really, when you want to use your Laser indoors visibly without using a receiver then green is worth considering but for outdoor work using a receiver there is very little advantage in going green. Its worth noting that many machine mounted receivers for rotating laser will only work with red beam but this is beginning to change and machine receiver capable of picking up green rotating beams are starting to appear.
What about cost? To produce a green laser beam a green laser diode is used, these diodes are currently substantially more expensive than the more common red variety (although cost are coming down). For rotating lasers typically only one diode is used so the additional cost for green is relatively small. In multiline lasers there can sometimes be in excess of 6 diodes so to make an all green beam multi line laser can be double the overall cost compared to the red beam version.
Green diodes also tend to suffer more from effects from heat, this being when the diode gets too hot, e.g. when in full sun, the intensity dims down, all diodes do this but green diodes tend to dim down at lower temperatures. Note that once the ambient temperature drops the diode will normally return to its previous intensity. Green diodes also tend to use more power but this does vary from manufacturer to manufacturer. There have also been questions raised about the longevity or lifespan of green diodes to red but myself I have yet to see a significant difference between the two colors in quality laser levels.
So in conclusion if yo are installing internal walls, kitchens, tiles, ceilings in fact any interior work a green beam laser will provide a brighter clear line. For outdoor general site levelling, plumbing and earth moving their is not great advantage in going green and in fact you may cause yourself problems if you want to add a machine receiver to your tool kit later on.