From: mscir@yahoo.com   
      
   On 8/21/2015 3:50 PM, RichD wrote:   
   > Lasers are useful for their low dispersion.   
   >   
   > What I wonder is, why are they necessary for the   
   > most common applications?  e.g. bar codes, CD readers,   
   > etc.   
   >   
   > My point is that collimated, non-coherent light   
   > was developed long before the laser.  So what makes   
   > a laser superior?   
   >   
   > --   
   > Rich   
      
   Knowing nothing about lasers I found this discussion interesting. On   
   what may be a related note, does anyone know anything about the lasers   
   used in the devices they try to find gravity waves with?   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)