Red Beam

[Cysco00]

Hey guys, question, since I am a noob at lasers don't flame too hard...LOL. I just purchased a Red Laser, Jayrob built as mentioned below:

Someone is going to get a great deal!

Especially on the copper heatsink build...

That is one sweet build using a Pioneer 115D long open can diode with the Meredith glass module and copper heatsink in a side button host with FlexDrive/3 X AAA.

Here is a couple of pictures I took of the build when I first built it:

If you want to see the inside of the build, and how it is put together... See this tutorial:
http://laserpointerforums.com/laser_pointer_forums_3/forum/showthread.php?t=36804
Jay

I also have an Infiniti 95mw Green, and another Jayrob built 4x blu-ray in the same host as above. I can see the beam extremely well with my green, very well with my blu-ray, but can't really see the red at all, unless with the help of smoke, yet it's the most powerful in my collection. Why? I have seen several pics on this board with some reds that are have as good a beam as the greens, yet mine doesn't, I am sure it has something to do with wavelength but could someone please explain....thanks.

Thanks.

Cisco C.

 

[AndyM]

I also cannot see the beam of my 200mw red laser. The reason for this is because red is far less visible to the human eye then green. Also, many people see bluray differently then others. Consider yourself lucky that you can see your bluray beam so clearly

 

[Eku]

Same here, my reds are horrible for beaming yet my blueray for me is great but green blows them both away!

 

[lasersbee]

Exactly.... the human eye's peak sensitivity is near the Green wavelengths..
Either side of that wavelength the sensitivity falls off..
That means a 100mW Green (532nm) Laser will look a lot brighter than a 100mW
Red (650nm) Laser and a Whole lot brighter than a 100mW Blu-Ray (405nm) Laser
or a 100mW IR (808nm) Laser....


Jerry

 

[Darkarmyofone]

lasersbee just WHOMPED it lol, listen to him, he knows his stuff.

 

[themandalorian]

You absolutely need smoke? My friends 200mw red doesn't need smoke but is definately brighter than my green 5mw at least/

and Dark, Lol Recess?

 

[Cysco00]

Ah, I see, thanks for the explanation guys, I appreciate it. I am enjoying the heck out of it nonetheless!!

Cheers,

Cisco C.

 

[ElektroFreak]

There is a tiny bit more to it as well. The beams of a red and a blu-ray of the same power both have about the same relative brightness on the human vision sensitivity curve, but the beam from a blu-ray will always be more visible. This is due to Rayleigh scattering. As you probably know, to see a laser beam requires matter to be floating in the air for the light to reflect from. Along with being reflected off of floating particles in the air, blu-ray light has such a short wavelength it gets reflected off the molecules of the air itself. This phenomenon is also responsible for the fact that the sky is blue, and results in blue and violet lasers having visible beams even when other lasers (particularly red) do not. The shorter the wavelength, the more this phenomoenon occurs.

 

[Low-Q]

There is a tiny bit more to it as well. The beams of a red and a blu-ray of the same power both have about the same relative brightness on the human vision sensitivity curve, but the beam from a blu-ray will always be more visible. This is due to Rayleigh scattering. As you probably know, to see a laser beam requires matter to be floating in the air for the light to reflect from. Along with being reflected off of floating particles in the air, blu-ray light has such a short wavelength it gets reflected off the molecules of the air itself. This phenomenon is also responsible for the fact that the sky is blue, and results in blue and violet lasers having visible beams even when other lasers (particularly red) do not. The shorter the wavelength, the more this phenomoenon occurs.

Further - the shorter wavelength, the more it burns. A 50mw violet laser burns way much better your skin than a 1W 808nm laser...