From: pcdhobbs@gmail.com   
      
   >What happens at the point of intersection of 2 lasers.   
   >If 2 lasers of different colour intersect, what will be happening   
   >at the point of intersection? Won't colour mixing happen??   
   >Won't that point where the lasers intersect be of different colour?   
   >For example if we use a green and a red laser then will not the point   
   >of intersection be yellow, if we use red and blue will not the point   
   >of intersection be magenta? The lasers are intersecting just in air.   
      
   In the absence of scattering, nothing happens whatsoever. The beams pass   
   through each other without even noticing.   
      
   If the air is dusty, the colours in the scattered light will mix in much the   
   same way as with LEDs. This is a purely visual effect, though--you won't get   
   additional wavelengths, because the scattering is linear.   
      
   Cheers   
      
   Phil Hobbs   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)