Re: TIRF and p- s-polarized incident linght

Posted by Shigeo Watanabe on
URL: http://confocal-microscopy-list.275.s1.nabble.com/paper-help-tp4115966p4212212.html


Dear All,

I have previouly asked how polarized the P- and S-polarized light are at TIRF illumination.
Thanks to John, now I get to know that P-polarized light is converted to "cartwheel" polarized light while S-polized light is intact.
As he suggested I read the review of Dan Axelrod about the effect(or problem) of this cartwheel polized light when observing the sample.
What I understand in his review is that cartwheel light excites only molecules which is parallel to z-axis.

Researchers who I talked with about TIRF problem also mentioned that normal TIRF system which use single incident light from one entering direction excite only a fraction of  molecules which is paralle to poloized evanescent light direction and then they prefer to use the ring-like illumination for TIRF to excite every single molecules.

Now I am confused about the actual TIRF problem.
Quesitons I have are these.
1)Does evanescent light excite the only molecules which are paralle to polarization of evanescent light because of cartwheel polarized light even when incident light is non-polarized light???
I am wondering what the actual polarization of evanescent light produced by non-polarized incident light, which is mixture of P- and S- polarized light.

2)Do commercial TIRF systems have this polarized problem? Do they use single incident light or ring-like incident light?


I appreciate if anyone help to answer these questions.

Sincerely
Shigeo Watanabe
Hamamatsu Photonics KK