Can you see a laser beam in a Class 100 cleanroom?

[KMitch]

How much of the beam that we see from a powerful laser pointer is visible due to particles in the air? If you were to use your laser in an environment without any particles, would you still be able to see the beam due only to Rayleigh scattering off the air molecules?

I work in a Class 100 cleanroom, which means that there are only 3,500 particles per cubic foot that are larger than 100 nanometers (this also makes it super convenient to apply screen protection on my phone ). In urban environments, the particle concentration is 10,000X higher with 35,000,000 particles per cubic foot. I work odd hours when no one else is around, and I could probably shine the beam of a 3W blue laser for a short time in a safe area into a beam dump with the lights partially turned off. Do you think the beam will be visible?

 

[Deleted member 42751]

Yes, certainly. Rayleigh scattering accounts for most of the beam visibility, especially with shorter wavelengths like your 3W blue.

 

[KMitch]

Thanks Sta, that was what I thought, but all the misinformation online had me doubting myself.

 

[Trendkilla254]

Thanks Sta, that was what I thought, but all the misinformation online had me doubting myself.

Hey KMitch you are pretty close. I'm north of Temple in Troy. You wouldn't happen to have a Laser Power Meter would you?

 

[KMitch]

Unfortunately not. I got into contact with laserface a couple weeks ago before I left the country on vacation, but I'm having trouble getting back into touch with him now. He has a LPM and offered to help test my new 3W blue and boosted "15 mW" Optotronics green. I'm not seeing a difference between half power and full power on the blue, so I'd like to test it out. If I hear back from him, I'll let you know by PM.

 

[WizardG]

I can see my 1.1W 445 in a class 1 clean room. Just don't tell the powers that be around here I took the laser into the clean lab