just an experiment
(Note:  This laser will set wood, paper or first-fire mix aflame near the muzzle)
click -> stills or video

(click on images for full size)
Note: The bright green cover on the laser is a safety cap
Note also that using a blue beam for military applications wouldn't be good.  Because short wavelength light re-radiates/scatters by the atmosphere much more than red or IR
(Rayleigh Scattering - why the sky is blue and why sunsets are red), the beam of this laser is 445nm (Indigo) - believe it or not - my next one will be a 2000mW model!
On another of my pages is the beginning of a 1000yd covert illuminator I was making out of a 1300 mW near-IR laser
(My laser other project and more - click)

My gear has been evolving.  Mossie Midnight 12 o'clock light mount with SureFire X300
very early production Bushmaster Lower, no vertical grip
Daniel Defense Omega 7 floating handguard, EOTech EXP S3, G23.FTS 3x magnifier, Magpul CTR stock, extended range flip-up rear peep, Vickers VCAS sling
and for the moment my laser project.

The fluorscent green is a safety cap.

(I unfocused the beam just to make sure it wouldn't set the curtains on fire)
btw -I am as careful with this laser as I am with a firearm, in fact it scares me more
out to at least 50ft it would have the same effect on an eye as a nuclear flash including reflected light!
(untouched photo)

Shot with no light using a Sony camcorder with Nightshot (near-IR)

SureFire X300 with Mossie Midnight Mount

remember, this laser will set wood on fire near the muzzle

also remember these frames are taken in IR so the blue beam is not as bright.
Think of it as looking at a red light through a blue filter (or visa -versa), you'd
barely see the red.  This is nearly pure Indigo (445nm) viewed in near-IR (probably seeing only about 750nm-900nm)

... I made sure there were no aircraft...

Video taken with a Sony Nighshot in near-IR

The beam is Blue so it is very much brighter than seems here.
(i.e. it's like looking at a blue bulb through a dark red filter)