Why don't red laser pens produce straight beams like green ones?

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MythioS
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Hope this is an apropriate thread to be asking this.. but I am curious if anyone knows a cheap way to get a straight red laser beam?

I found this green laser pen on the net and it has a fluid light from source to point but they say the red ones simply don't have the technology or something...

the smaller the laser generator or what not the better, which is why i ended up searching the pen ones.

Thanks
 
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Just a few years ago all laser pointers were red. I would be surprised if you can't get them anymore. If anything, they should be cheaper.

Njorl
 
straight red laser beam

Its a good thing your looking for a straight red laser beam , those curved ones aren't cheep.
 
ive been seeing pen lights in red but they only show the dot at the end of the beam. I am looking for something that will show the beam itself.
 
Air does not effectively scatter red light, so no red laser will "show its beam" in air. You'd need to put some mist or dust or fog in the way to scatter the beam and make it visible.

Green laser light, on the other hand, is scattered by air -- though only slightly -- so you can see the beam. However, in an enclosure about the size of a room, there's not enough scattering to see the beam of a green laser either. You need about a kilometer of air and a dark night to be able to see a green laser's beam. They work great for pointing out stars to people, for example.

If this is for a science project or something on a table-top, the best way to make a laser's beam visible is simply to use one of those party-fog machines.

- Warren
 
Well it doesn't necessarily have to be an official laser. of there were a way to produce the same effect? I am not sure of a light that would emit such a straight line but perhaps someone else does