Different wavelengths

[Des]

Just a quick question, sorry if it's been asked many times prior, but at what wavelenth and mW is the beam of a green laser visible in a dark room?

 

[CynicalBrad]

You should consider introducing yourself in the welcome section so we can get to know you a little.

As for your question, 1mW of 532nm green has a faintly visible beam in a dark room so here is a handy calculator.

Relative Laser Beam Brightness Calculator: (532nm 1mw) vs. (450nm 9.55mw)

You can leave the top two boxes in this alone and change the wavelength in the bottom box and put a "?" in the second power box and it will tell you about what power will be as visible as 532nm at 1mW.

 

[Encap]

yes post something about yourself and your location in the Welcome sub-forum first if you expect reasonable help with questions

You can use the LPF data base search at the bottom of the page to answer most questions

 

[Lifetime17]

Hi Des,
The guys are correct we all like to know your location on this planet and a little about your endeavors on LPF. As for your question a 520nm diode/9mm/ at 1 W i bright as the sun in a dark room . Some of the higher power 532's are really bright also in a labby. Bob Mac has a really awesome set up i tested it out and it is beyond bright i had to wear welding glasses.

Rich

 

[GSS]

I would say 30mw would be the starting point in a dark room for decent visibility....This should give a idea,
http://www.youtube.com/watch?v=woiTedSKPrk&playnet_from=TL&videos=ihv8Xh_HXIM&feature=sub

 

[Lifetime17]

I would say 30mw would be the starting point in a dark room for decent visibility....This should give a idea,
http://www.youtube.com/watch?v=woiTedSKPrk&playnet_from=TL&videos=ihv8Xh_HXIM&feature=sub

Hi GSS,
Great answer to his question that sums it up completely . As Richard Dawson would say thats the #1 answer..

Rich

 

[hakzaw1]

Be nice and you will fit in here.. none of the suggestions should bother you..if they do..sorry... this may not be the right forum for you.

 

[american_eagle]

I tested it 2 years ago as i started my laser „career“ with low powered green lasers. Around 30-40mW you will starting to see a beam in the dark room.
Cheers,
Nasser

 

[hakzaw1]

I tested it 2 years ago as i started my laser „career“ with low powered green lasers. Around 30-40mW you will starting to see a beam in the dark room.
Cheers,
Nasser

WHAT!?

NEVER saw ANY greens that were not see-able in the dark--even 5 mW can easily be seen.

neg rep

 

[Zom-B]

True. In a pitch dark room and with the right angle I saw the beam on a 0.3mW PL520 (525nm) at just lasing threshold. My LPM (Laser power meter) is very inaccurate in the low region so even though it read 0.3mW it could actually be anywhere between 0.2 and 1.0mW.

 

[american_eagle]

Okay, thanks for sharing your experiences this might help him alot. I am sorry for any wrong informations and inconveniences but it shows that I am no more really informed about that topic. :S

 

[hakzaw1]

Okay, thanks for sharing your experiences this might help him alot. I am sorry for any wrong informations and inconveniences but it shows that I am no more really informed about that topic. :S

no worries
it was a very minor faux pas

we have seen MUCH worse--like advice that could get someone harmed or sending them to an awful place to buy lasers.

You may see me giving you a +rep to even things out..just do not be afraid to say 'I don't know' or say nothing. :tsk: