Is a beam possible with <5mW of 405nm?

[micheal rosen]

^Neat! 633nm?

It's strange though, sometimes the beam on my Electra looked grayish like, very strange

-Alex

Thats because (now i don't know the specifics, but i know the general reason) when you get to such a short wavelength, the color receptors in your eyes have a hard time seeing it. So, at low powers, instead of color, the light detection cells are used to observe the beam. Those cells can only detect differences in amount of light/brightness, making the beam colorless.


nice laser though! i really think you should try some of laserbtb's 5mW pens, they have been shown to be truly below 5mW and their quality isn't bad.

 

[NightExplorer96]

Thats because (now i don't know the specifics, but i know the general reason) when you get to such a short wavelength, the color receptors in your eyes have a hard time seeing it. So, at low powers, instead of color, the light detection cells are used to observe the beam. Those cells can only detect differences in amount of light/brightness, making the beam colorless.


nice laser though! i really think you should try some of laserbtb's 5mW pens, they have been shown to be truly below 5mW and their quality isn't bad.

Hey micheal, good to see you back!

Yeah, I thought it was something like that. Since there just isn't enough light coming in, your rods take over and just see gray?

I've also had a 650nm laserbtb pointer in the past, pretty neat stuff. Might need to get their 515nm one

-Alex

 

[Pikablu]

I have an overspec ebay 405nm that cost four dollars, I can clearly see the beam in a dark room, no smoke or fog.

 

[Rivem]

I have an overspec ebay 405nm that cost four dollars, I can clearly see the beam in a dark room, no smoke or fog.

I have one of these as well, and when I'm dark adapted, I can definitely see the beam in the very dry, very clear desert air I live in. No idea of the actual power since I don't have much comparison though. 405nm does seem pretty bright to me though.

 

[Isaac Clarke]

believe it or not some people can't see 405nm at all.

 

[Rivem]

believe it or not some people can't see 405nm at all.

A few people have failed to see mine, so I believe you. Maybe people that have slight UV damage to their eyes from sunlight or night-blindness are insensitive to it. It seemed almost as bright as 660nm when I saw two 5mW pointers a friend had side by side to me. Mine's brighter, but I've only seen the 5mW before. Looks like a nice rich violet to me.