Posted by
Shalin Mehta on
URL: http://confocal-microscopy-list.275.s1.nabble.com/Coverslip-tp592448p592452.html
Dear Sarah,
If you look at reflection passed through pin-hole you should be able to spot the air-glass and glass-air interface (i.e. top and bottom surfaces of the coverslip respectively) with sub-micron accuracy.
As light would refract on entering through top surface, you will need to apply simple correction to calculate coverslip thickness from z-distance measured by motor. From simple calculation, the correction should be:
t_coverslip/z_motor=cot(theta2)/cot(theat1), [just to avoid misreading cot is cotangent]
where theta1= half-aperture angle as per NA of the objective in air (i.e. inversin(NA)) and theta2= half-aperture angle after refraction from air-glass interface (therefore, theta1=1.51theta2).
But I am not sure whether the coverslip correction done by the objective will affect this correction factor!! May be those who understand internals of objectives more can comment on this.
Hope this helps
Shalin
On Mon, Feb 25, 2008 at 4:29 AM, Rietdorf, Jens <
[hidden email]> wrote:
Dear Sarah,
you could use reflections from the coverglass which are
characteristic for upper and lower edge of the cover glass and easy to
spot.
regards, jens
---
Dr.
Jens Rietdorf[hidden email]
Head
Microscopy
Novartis Research
Foundation
Friedrich-Miescher-Institute, wro1066.2.16 Maulbeerstr.66, CH-4058
Basel, Switzerland
phone +41(61)69-75172 mobil
+41 798284737
Email:rietdorf(at)fmi.ch
From: Confocal Microscopy List
[mailto:[hidden email]] On Behalf Of Sarah
Kefayati
Sent: Freitag, 22. Februar 2008 21:42
To:
[hidden email]
Subject: Coverslip
--
~~~~~~~~~~~~~~~~~~~~~~~~~
Shalin Mehta
mobile: +65-90694182
blog:
shalin.wordpress.com~~~~~~~~~~~~~~~~~~~~~~~~~~
Bioimaging Lab, Block-E3A, #7-10
Div of Bioengineering, NUS Singapore 117574
website:
http://www.bioeng.nus.edu.sg/optbioimaging/colin/index.html
Liver Cancer Functional Genomics Lab, #6-05
National Cancer Centre, Singapore 169610
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