The Green Laser pen, for us is still an experimental piece of kit, we have used it twice with pretty mixed results however we will continue with some experiments with it before we make a more permanent decision.
Green Laser Pointer
This pointer is significantly brighter (about 50 times) than a red laser pointer and because of its unusual colour it is much more noticeable. The green beam itself can be seen in mid-air in dark conditions, not just the laser beam dot. This allows the green laser pointer to be used for pointing to
star constellations. The green laser pointer can be seen at much greater distances than with a red laser pointer. Since green direct injection laser diodes aren't readily available, this pointer is based on the use of Diode Pumped Solid State Frequency Doubled (DPSSFD) laser technology. A high power IR laser diode at 808 nm pumps a tiny block of Nd:YVO4 generating light at 1,064 nm which feeds a KTP intracavity frequency doubler crystal to produce the green beam at 532 nm.
This picture is slightly exaggerated to make the point, however with some careful arrangement of small mirrors you can easily use the laser pointer to go around objects or rooms, the reason this may be interesting is if something should break the beam or distort it in some way the rest of the
grid wont work, it would fail so not only is it easy to see it is also easy to see where etc.
One of the things we have been looking at so far is attaching these to out CCTV cameras, which makes the viewing of the footage interesting (in the loosest scene of the word) as we are looking for any distortion to the grid of laser light. The con side is in the room using your eyes to see it
makes everything extremely 2D and confusing .