- Sep 20, 2013
Congratulations on your 9000th post, diachi. I'm creeping up on 8000 myself. :yh:
Your question is far too vague to give a simple answer. Under what conditions will you be using this laser?For a standard 650 nm red laser, what's the general rule for power necessary to produce a visible beam? I'm not talking a lightsaber, just something that will distinguish it from a dog toy. I'm very skeptical of buying 30mW for a build and being able to see the difference.
Exactly--it is a meaningless question -- there is no visible laser "beam" in a vacuum regardless of power 1/10W or 1MW no visible beam---a visible beam is a function of reflections possible in a given atmosphereYour question is far too vague to give a simple answer. Under what conditions will you be using this laser?
/\ ThisIt depends on how clean the air is too.
In a smokey room even a 5 mW 650 nm laser will produce a visible beam, but in cleaner air much larger power levels will be required.
In pure air, with no particles floating around etc, you can see a beam only due to scattering at a molecular level. This effect is -very- small. If you were standing in a well lit cleanroom there could be a 10 watt green beam passing a meter in front of your eyes without you noticing it at all, since there is nothing 'big' in the air to scatter that light and ambient light is so bright it will swamp out any molecular level scattering easily.
Man, I knew you had to be a Zappa fan. I imagine you have quite the taste, we'll need to share some music some time.Oh, that wouldn't get you banned. "Torture Never Stops" is tame by Zappa standards. Do you remember, "If she were my daughter...." "What would you do, daddy?" "Well,if she were my daughter....." "What would you do, daddy?" "I'd cover that girl in chocolate syrup and boogie 'til the cows come home." Man, there were so very many like that.