From: rrllff@yahoo.com   
      
   On Thursday, April 3, 2014 5:38:28 PM UTC-4, Phil Hobbs wrote:   
   > On 04/03/2014 04:20 PM, Helpful person wrote:   
   >    
   > > Scattering is a problem.  However, I built a prototype about 10   
   > > years ago that penetrated (in vivo) more than 0.5mm into tissue   
   > > with good resolution.  Using a wavelength of 850nm gave a   
   > > reasonable compromise of reduced scattering while still keeping   
   > > a reasonable response for the CCD camera.   
   > >   
   >    
   > Nice.  I expect that blood is harder, though, because there's more index    
   > contrast at the cell boundaries, but I'm not entirely sure.   
   > I do know that you can do OCT a few millimeters in.   
   >    
   > Cheers   
   > Phil Hobbs   
   >    
   I was looking for nuclei (about 14 microns) through a laparoscope, not blood   
   cells.  The target was visible due to the refractive index change at   
   boundaries.  I had some nice real time recordings (video) of what I describe   
   as "friendly" tissue.  Not yet    
   nuclei, but very close.  Quite a challenge obtaining decent signal/noise   
   through many lenses.  Unfortunately my funding ran out before being able to   
   progress to the next stage.   
      
   http://www.richardfisher.com   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)