Non-glass coverslips?

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tocharian
Posts: 5
Joined: Thu Nov 29, 2018 12:59 pm

Non-glass coverslips?

#1 Post by tocharian » Tue Jul 23, 2019 11:26 am

My experiments requires the use of conductive coverslips.

I recently used ITO coated polymer for this, and I wanted to visualize bacteria. However, under brightfield, using 40x dry objective and 100x oil objective I could not see actual shapes of bacteria, only blur bright spheres.

The polymer, PET, had a refractive index of 1.575 (according to some webpage, not the manufacturer), not much different from that of glass. The ITO layer (conductive) had a much higher refractive index, maybe >2, but is <0.5 um thick. I suspected that the coverslip thickness was the problem, but I tried 50 um and 185 um polymer, and produced similar results (my objectives are designed for 170 um coverslips).

Years ago, in another lab, I was shown that obervsations could be made with ITO-coated 150 um glass. However, such ITO-glass was customized with high cost. Also, there may be some details I don't know about such ITO-glasses, ommiting which can again lead to failed observations.

Therefore, I really want to know the main reason that my setup did not work, thanks!

apochronaut
Posts: 2733
Joined: Fri May 15, 2015 12:15 am

Re: Non-glass coverslips?

#2 Post by apochronaut » Tue Jul 23, 2019 11:59 am

The polymer has a low level of pellucidity or optical transparency causing excessive scattering of rays.

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