Josef,

just guessing: the microlenses which the excitation light has to pass mess
up the polarization.

http://www.yokogawa.com/scanner/principles/images/genri6.gif

Michael


> Dear all,
>
> People from Andor told me that light loses polarization when travelling
> through the disc - you have to re-polarize it for dooing anisotropy
> imaging.
> I am simply curious - Can anybody provide me with a physical explanation?
>
> Cheers
>
> Josef