From: luweitest@address.invalid   
      
   On 2015-12-8 12:34, Lu Wei wrote:   
   >   
   > The reflectance r = (1-n)/(1+n) at normal incidence, so the phase change   
   > at interface = Arg(r). If n is real (dielectric), Arg(r) = -π; if n is   
   > complex (metal), as long as abs(n)>>1, Arg(r) is near -π too.   
      
   correction: Arg(r) is (near) π, not -π.   
      
      
   --   
   Regards,   
   Lu Wei   
   PGP key ID: 0x92CCE1EA   
      
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