What can a 100mW handheld laser do that a 10mW or 1W can't?

[julianthedragon]

Just a vague question that crossed my mind and left me curious as to what other members would have to say. I own a few lasers in the 100-200mW range and they sort of occupy a space that's too powerful to be safe, but not powerful enough to pack a punch. Mostly pretty to look at (outdoors) or good for popping balloons/tiny engravements.

What are your special uses, real or imagined, for handhelds at the 100mW caliber? For example, <5mW are good for presentations, and 1W are good for cutting and melting things.

Looking for anything whether scientific, practical, or just-for-fun.

Edit: One example that just occured to me is that I use these for lightpainting photography, where lower-powered would be invisible but higher-powered would be overkill for a multitude of reasons. Thanks!

 

[HunterJackson]

They are safer than 1w because lower hazard distance, and they do not burn skin or start fires

 

[whysoserious11311]

50-100mW, occasionally up to 150mW; are generally the power thresholds for many microscopy techniques requiring fluorescence excitation. Power output is not always for a focused beam, so realistically by the time it becomes highly collimated over a large area the mW/cm^2 is much less - hence the need for 100mW or more.

mesoSPIM.org is an open source "DIY" light sheet microscope project. Set you back about a quarter of a million to build one, but uses a bunch of 150mW lasers.